1 /* 2 * BSS table 3 * Copyright (c) 2009-2012, 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 "utils/includes.h" 10 11 #include "utils/common.h" 12 #include "utils/eloop.h" 13 #include "common/ieee802_11_defs.h" 14 #include "drivers/driver.h" 15 #include "wpa_supplicant_i.h" 16 #include "config.h" 17 #include "notify.h" 18 #include "scan.h" 19 #include "bss.h" 20 21 22 /** 23 * WPA_BSS_EXPIRATION_PERIOD - Period of expiration run in seconds 24 */ 25 #define WPA_BSS_EXPIRATION_PERIOD 10 26 27 #define WPA_BSS_FREQ_CHANGED_FLAG BIT(0) 28 #define WPA_BSS_SIGNAL_CHANGED_FLAG BIT(1) 29 #define WPA_BSS_PRIVACY_CHANGED_FLAG BIT(2) 30 #define WPA_BSS_MODE_CHANGED_FLAG BIT(3) 31 #define WPA_BSS_WPAIE_CHANGED_FLAG BIT(4) 32 #define WPA_BSS_RSNIE_CHANGED_FLAG BIT(5) 33 #define WPA_BSS_WPS_CHANGED_FLAG BIT(6) 34 #define WPA_BSS_RATES_CHANGED_FLAG BIT(7) 35 #define WPA_BSS_IES_CHANGED_FLAG BIT(8) 36 37 38 static void wpa_bss_set_hessid(struct wpa_bss *bss) 39 { 40 #ifdef CONFIG_INTERWORKING 41 const u8 *ie = wpa_bss_get_ie(bss, WLAN_EID_INTERWORKING); 42 if (ie == NULL || (ie[1] != 7 && ie[1] != 9)) { 43 os_memset(bss->hessid, 0, ETH_ALEN); 44 return; 45 } 46 if (ie[1] == 7) 47 os_memcpy(bss->hessid, ie + 3, ETH_ALEN); 48 else 49 os_memcpy(bss->hessid, ie + 5, ETH_ALEN); 50 #endif /* CONFIG_INTERWORKING */ 51 } 52 53 54 /** 55 * wpa_bss_anqp_alloc - Allocate ANQP data structure for a BSS entry 56 * Returns: Allocated ANQP data structure or %NULL on failure 57 * 58 * The allocated ANQP data structure has its users count set to 1. It may be 59 * shared by multiple BSS entries and each shared entry is freed with 60 * wpa_bss_anqp_free(). 61 */ 62 struct wpa_bss_anqp * wpa_bss_anqp_alloc(void) 63 { 64 struct wpa_bss_anqp *anqp; 65 anqp = os_zalloc(sizeof(*anqp)); 66 if (anqp == NULL) 67 return NULL; 68 anqp->users = 1; 69 return anqp; 70 } 71 72 73 /** 74 * wpa_bss_anqp_clone - Clone an ANQP data structure 75 * @anqp: ANQP data structure from wpa_bss_anqp_alloc() 76 * Returns: Cloned ANQP data structure or %NULL on failure 77 */ 78 static struct wpa_bss_anqp * wpa_bss_anqp_clone(struct wpa_bss_anqp *anqp) 79 { 80 struct wpa_bss_anqp *n; 81 82 n = os_zalloc(sizeof(*n)); 83 if (n == NULL) 84 return NULL; 85 86 #define ANQP_DUP(f) if (anqp->f) n->f = wpabuf_dup(anqp->f) 87 #ifdef CONFIG_INTERWORKING 88 ANQP_DUP(venue_name); 89 ANQP_DUP(network_auth_type); 90 ANQP_DUP(roaming_consortium); 91 ANQP_DUP(ip_addr_type_availability); 92 ANQP_DUP(nai_realm); 93 ANQP_DUP(anqp_3gpp); 94 ANQP_DUP(domain_name); 95 #endif /* CONFIG_INTERWORKING */ 96 #ifdef CONFIG_HS20 97 ANQP_DUP(hs20_operator_friendly_name); 98 ANQP_DUP(hs20_wan_metrics); 99 ANQP_DUP(hs20_connection_capability); 100 ANQP_DUP(hs20_operating_class); 101 #endif /* CONFIG_HS20 */ 102 #undef ANQP_DUP 103 104 return n; 105 } 106 107 108 /** 109 * wpa_bss_anqp_unshare_alloc - Unshare ANQP data (if shared) in a BSS entry 110 * @bss: BSS entry 111 * Returns: 0 on success, -1 on failure 112 * 113 * This function ensures the specific BSS entry has an ANQP data structure that 114 * is not shared with any other BSS entry. 115 */ 116 int wpa_bss_anqp_unshare_alloc(struct wpa_bss *bss) 117 { 118 struct wpa_bss_anqp *anqp; 119 120 if (bss->anqp && bss->anqp->users > 1) { 121 /* allocated, but shared - clone an unshared copy */ 122 anqp = wpa_bss_anqp_clone(bss->anqp); 123 if (anqp == NULL) 124 return -1; 125 anqp->users = 1; 126 bss->anqp->users--; 127 bss->anqp = anqp; 128 return 0; 129 } 130 131 if (bss->anqp) 132 return 0; /* already allocated and not shared */ 133 134 /* not allocated - allocate a new storage area */ 135 bss->anqp = wpa_bss_anqp_alloc(); 136 return bss->anqp ? 0 : -1; 137 } 138 139 140 /** 141 * wpa_bss_anqp_free - Free an ANQP data structure 142 * @anqp: ANQP data structure from wpa_bss_anqp_alloc() or wpa_bss_anqp_clone() 143 */ 144 static void wpa_bss_anqp_free(struct wpa_bss_anqp *anqp) 145 { 146 if (anqp == NULL) 147 return; 148 149 anqp->users--; 150 if (anqp->users > 0) { 151 /* Another BSS entry holds a pointer to this ANQP info */ 152 return; 153 } 154 155 #ifdef CONFIG_INTERWORKING 156 wpabuf_free(anqp->venue_name); 157 wpabuf_free(anqp->network_auth_type); 158 wpabuf_free(anqp->roaming_consortium); 159 wpabuf_free(anqp->ip_addr_type_availability); 160 wpabuf_free(anqp->nai_realm); 161 wpabuf_free(anqp->anqp_3gpp); 162 wpabuf_free(anqp->domain_name); 163 #endif /* CONFIG_INTERWORKING */ 164 #ifdef CONFIG_HS20 165 wpabuf_free(anqp->hs20_operator_friendly_name); 166 wpabuf_free(anqp->hs20_wan_metrics); 167 wpabuf_free(anqp->hs20_connection_capability); 168 wpabuf_free(anqp->hs20_operating_class); 169 #endif /* CONFIG_HS20 */ 170 171 os_free(anqp); 172 } 173 174 175 static void wpa_bss_remove(struct wpa_supplicant *wpa_s, struct wpa_bss *bss, 176 const char *reason) 177 { 178 if (wpa_s->last_scan_res) { 179 unsigned int i; 180 for (i = 0; i < wpa_s->last_scan_res_used; i++) { 181 if (wpa_s->last_scan_res[i] == bss) { 182 os_memmove(&wpa_s->last_scan_res[i], 183 &wpa_s->last_scan_res[i + 1], 184 (wpa_s->last_scan_res_used - i - 1) 185 * sizeof(struct wpa_bss *)); 186 wpa_s->last_scan_res_used--; 187 break; 188 } 189 } 190 } 191 dl_list_del(&bss->list); 192 dl_list_del(&bss->list_id); 193 wpa_s->num_bss--; 194 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR 195 " SSID '%s' due to %s", bss->id, MAC2STR(bss->bssid), 196 wpa_ssid_txt(bss->ssid, bss->ssid_len), reason); 197 wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id); 198 wpa_bss_anqp_free(bss->anqp); 199 os_free(bss); 200 } 201 202 203 /** 204 * wpa_bss_get - Fetch a BSS table entry based on BSSID and SSID 205 * @wpa_s: Pointer to wpa_supplicant data 206 * @bssid: BSSID 207 * @ssid: SSID 208 * @ssid_len: Length of @ssid 209 * Returns: Pointer to the BSS entry or %NULL if not found 210 */ 211 struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid, 212 const u8 *ssid, size_t ssid_len) 213 { 214 struct wpa_bss *bss; 215 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid)) 216 return NULL; 217 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 218 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 && 219 bss->ssid_len == ssid_len && 220 os_memcmp(bss->ssid, ssid, ssid_len) == 0) 221 return bss; 222 } 223 return NULL; 224 } 225 226 227 static void calculate_update_time(const struct os_reltime *fetch_time, 228 unsigned int age_ms, 229 struct os_reltime *update_time) 230 { 231 os_time_t usec; 232 233 update_time->sec = fetch_time->sec; 234 update_time->usec = fetch_time->usec; 235 update_time->sec -= age_ms / 1000; 236 usec = (age_ms % 1000) * 1000; 237 if (update_time->usec < usec) { 238 update_time->sec--; 239 update_time->usec += 1000000; 240 } 241 update_time->usec -= usec; 242 } 243 244 245 static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src, 246 struct os_reltime *fetch_time) 247 { 248 dst->flags = src->flags; 249 os_memcpy(dst->bssid, src->bssid, ETH_ALEN); 250 dst->freq = src->freq; 251 dst->beacon_int = src->beacon_int; 252 dst->caps = src->caps; 253 dst->qual = src->qual; 254 dst->noise = src->noise; 255 dst->level = src->level; 256 dst->tsf = src->tsf; 257 258 calculate_update_time(fetch_time, src->age, &dst->last_update); 259 } 260 261 262 static int wpa_bss_known(struct wpa_supplicant *wpa_s, struct wpa_bss *bss) 263 { 264 struct wpa_ssid *ssid; 265 266 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) { 267 if (ssid->ssid == NULL || ssid->ssid_len == 0) 268 continue; 269 if (ssid->ssid_len == bss->ssid_len && 270 os_memcmp(ssid->ssid, bss->ssid, ssid->ssid_len) == 0) 271 return 1; 272 } 273 274 return 0; 275 } 276 277 278 static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss) 279 { 280 return bss == wpa_s->current_bss || 281 os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 || 282 os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0; 283 } 284 285 286 static int wpa_bss_remove_oldest_unknown(struct wpa_supplicant *wpa_s) 287 { 288 struct wpa_bss *bss; 289 290 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 291 if (!wpa_bss_known(wpa_s, bss)) { 292 wpa_bss_remove(wpa_s, bss, __func__); 293 return 0; 294 } 295 } 296 297 return -1; 298 } 299 300 301 static int wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s) 302 { 303 struct wpa_bss *bss; 304 305 /* 306 * Remove the oldest entry that does not match with any configured 307 * network. 308 */ 309 if (wpa_bss_remove_oldest_unknown(wpa_s) == 0) 310 return 0; 311 312 /* 313 * Remove the oldest entry that isn't currently in use. 314 */ 315 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 316 if (!wpa_bss_in_use(wpa_s, bss)) { 317 wpa_bss_remove(wpa_s, bss, __func__); 318 return 0; 319 } 320 } 321 322 return -1; 323 } 324 325 326 static struct wpa_bss * wpa_bss_add(struct wpa_supplicant *wpa_s, 327 const u8 *ssid, size_t ssid_len, 328 struct wpa_scan_res *res, 329 struct os_reltime *fetch_time) 330 { 331 struct wpa_bss *bss; 332 333 bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len); 334 if (bss == NULL) 335 return NULL; 336 bss->id = wpa_s->bss_next_id++; 337 bss->last_update_idx = wpa_s->bss_update_idx; 338 wpa_bss_copy_res(bss, res, fetch_time); 339 os_memcpy(bss->ssid, ssid, ssid_len); 340 bss->ssid_len = ssid_len; 341 bss->ie_len = res->ie_len; 342 bss->beacon_ie_len = res->beacon_ie_len; 343 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len); 344 wpa_bss_set_hessid(bss); 345 346 if (wpa_s->num_bss + 1 > wpa_s->conf->bss_max_count && 347 wpa_bss_remove_oldest(wpa_s) != 0) { 348 wpa_printf(MSG_ERROR, "Increasing the MAX BSS count to %d " 349 "because all BSSes are in use. We should normally " 350 "not get here!", (int) wpa_s->num_bss + 1); 351 wpa_s->conf->bss_max_count = wpa_s->num_bss + 1; 352 } 353 354 dl_list_add_tail(&wpa_s->bss, &bss->list); 355 dl_list_add_tail(&wpa_s->bss_id, &bss->list_id); 356 wpa_s->num_bss++; 357 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR 358 " SSID '%s'", 359 bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len)); 360 wpas_notify_bss_added(wpa_s, bss->bssid, bss->id); 361 return bss; 362 } 363 364 365 static int are_ies_equal(const struct wpa_bss *old, 366 const struct wpa_scan_res *new, u32 ie) 367 { 368 const u8 *old_ie, *new_ie; 369 struct wpabuf *old_ie_buff = NULL; 370 struct wpabuf *new_ie_buff = NULL; 371 int new_ie_len, old_ie_len, ret, is_multi; 372 373 switch (ie) { 374 case WPA_IE_VENDOR_TYPE: 375 old_ie = wpa_bss_get_vendor_ie(old, ie); 376 new_ie = wpa_scan_get_vendor_ie(new, ie); 377 is_multi = 0; 378 break; 379 case WPS_IE_VENDOR_TYPE: 380 old_ie_buff = wpa_bss_get_vendor_ie_multi(old, ie); 381 new_ie_buff = wpa_scan_get_vendor_ie_multi(new, ie); 382 is_multi = 1; 383 break; 384 case WLAN_EID_RSN: 385 case WLAN_EID_SUPP_RATES: 386 case WLAN_EID_EXT_SUPP_RATES: 387 old_ie = wpa_bss_get_ie(old, ie); 388 new_ie = wpa_scan_get_ie(new, ie); 389 is_multi = 0; 390 break; 391 default: 392 wpa_printf(MSG_DEBUG, "bss: %s: cannot compare IEs", __func__); 393 return 0; 394 } 395 396 if (is_multi) { 397 /* in case of multiple IEs stored in buffer */ 398 old_ie = old_ie_buff ? wpabuf_head_u8(old_ie_buff) : NULL; 399 new_ie = new_ie_buff ? wpabuf_head_u8(new_ie_buff) : NULL; 400 old_ie_len = old_ie_buff ? wpabuf_len(old_ie_buff) : 0; 401 new_ie_len = new_ie_buff ? wpabuf_len(new_ie_buff) : 0; 402 } else { 403 /* in case of single IE */ 404 old_ie_len = old_ie ? old_ie[1] + 2 : 0; 405 new_ie_len = new_ie ? new_ie[1] + 2 : 0; 406 } 407 408 if (!old_ie || !new_ie) 409 ret = !old_ie && !new_ie; 410 else 411 ret = (old_ie_len == new_ie_len && 412 os_memcmp(old_ie, new_ie, old_ie_len) == 0); 413 414 wpabuf_free(old_ie_buff); 415 wpabuf_free(new_ie_buff); 416 417 return ret; 418 } 419 420 421 static u32 wpa_bss_compare_res(const struct wpa_bss *old, 422 const struct wpa_scan_res *new) 423 { 424 u32 changes = 0; 425 int caps_diff = old->caps ^ new->caps; 426 427 if (old->freq != new->freq) 428 changes |= WPA_BSS_FREQ_CHANGED_FLAG; 429 430 if (old->level != new->level) 431 changes |= WPA_BSS_SIGNAL_CHANGED_FLAG; 432 433 if (caps_diff & IEEE80211_CAP_PRIVACY) 434 changes |= WPA_BSS_PRIVACY_CHANGED_FLAG; 435 436 if (caps_diff & IEEE80211_CAP_IBSS) 437 changes |= WPA_BSS_MODE_CHANGED_FLAG; 438 439 if (old->ie_len == new->ie_len && 440 os_memcmp(old + 1, new + 1, old->ie_len) == 0) 441 return changes; 442 changes |= WPA_BSS_IES_CHANGED_FLAG; 443 444 if (!are_ies_equal(old, new, WPA_IE_VENDOR_TYPE)) 445 changes |= WPA_BSS_WPAIE_CHANGED_FLAG; 446 447 if (!are_ies_equal(old, new, WLAN_EID_RSN)) 448 changes |= WPA_BSS_RSNIE_CHANGED_FLAG; 449 450 if (!are_ies_equal(old, new, WPS_IE_VENDOR_TYPE)) 451 changes |= WPA_BSS_WPS_CHANGED_FLAG; 452 453 if (!are_ies_equal(old, new, WLAN_EID_SUPP_RATES) || 454 !are_ies_equal(old, new, WLAN_EID_EXT_SUPP_RATES)) 455 changes |= WPA_BSS_RATES_CHANGED_FLAG; 456 457 return changes; 458 } 459 460 461 static void notify_bss_changes(struct wpa_supplicant *wpa_s, u32 changes, 462 const struct wpa_bss *bss) 463 { 464 if (changes & WPA_BSS_FREQ_CHANGED_FLAG) 465 wpas_notify_bss_freq_changed(wpa_s, bss->id); 466 467 if (changes & WPA_BSS_SIGNAL_CHANGED_FLAG) 468 wpas_notify_bss_signal_changed(wpa_s, bss->id); 469 470 if (changes & WPA_BSS_PRIVACY_CHANGED_FLAG) 471 wpas_notify_bss_privacy_changed(wpa_s, bss->id); 472 473 if (changes & WPA_BSS_MODE_CHANGED_FLAG) 474 wpas_notify_bss_mode_changed(wpa_s, bss->id); 475 476 if (changes & WPA_BSS_WPAIE_CHANGED_FLAG) 477 wpas_notify_bss_wpaie_changed(wpa_s, bss->id); 478 479 if (changes & WPA_BSS_RSNIE_CHANGED_FLAG) 480 wpas_notify_bss_rsnie_changed(wpa_s, bss->id); 481 482 if (changes & WPA_BSS_WPS_CHANGED_FLAG) 483 wpas_notify_bss_wps_changed(wpa_s, bss->id); 484 485 if (changes & WPA_BSS_IES_CHANGED_FLAG) 486 wpas_notify_bss_ies_changed(wpa_s, bss->id); 487 488 if (changes & WPA_BSS_RATES_CHANGED_FLAG) 489 wpas_notify_bss_rates_changed(wpa_s, bss->id); 490 } 491 492 493 static struct wpa_bss * 494 wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss, 495 struct wpa_scan_res *res, struct os_reltime *fetch_time) 496 { 497 u32 changes; 498 499 changes = wpa_bss_compare_res(bss, res); 500 bss->scan_miss_count = 0; 501 bss->last_update_idx = wpa_s->bss_update_idx; 502 wpa_bss_copy_res(bss, res, fetch_time); 503 /* Move the entry to the end of the list */ 504 dl_list_del(&bss->list); 505 #ifdef CONFIG_P2P 506 if (wpa_bss_get_vendor_ie(bss, P2P_IE_VENDOR_TYPE) && 507 !wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE)) { 508 /* 509 * This can happen when non-P2P station interface runs a scan 510 * without P2P IE in the Probe Request frame. P2P GO would reply 511 * to that with a Probe Response that does not include P2P IE. 512 * Do not update the IEs in this BSS entry to avoid such loss of 513 * information that may be needed for P2P operations to 514 * determine group information. 515 */ 516 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Do not update scan IEs for " 517 MACSTR " since that would remove P2P IE information", 518 MAC2STR(bss->bssid)); 519 } else 520 #endif /* CONFIG_P2P */ 521 if (bss->ie_len + bss->beacon_ie_len >= 522 res->ie_len + res->beacon_ie_len) { 523 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len); 524 bss->ie_len = res->ie_len; 525 bss->beacon_ie_len = res->beacon_ie_len; 526 } else { 527 struct wpa_bss *nbss; 528 struct dl_list *prev = bss->list_id.prev; 529 dl_list_del(&bss->list_id); 530 nbss = os_realloc(bss, sizeof(*bss) + res->ie_len + 531 res->beacon_ie_len); 532 if (nbss) { 533 unsigned int i; 534 for (i = 0; i < wpa_s->last_scan_res_used; i++) { 535 if (wpa_s->last_scan_res[i] == bss) { 536 wpa_s->last_scan_res[i] = nbss; 537 break; 538 } 539 } 540 if (wpa_s->current_bss == bss) 541 wpa_s->current_bss = nbss; 542 bss = nbss; 543 os_memcpy(bss + 1, res + 1, 544 res->ie_len + res->beacon_ie_len); 545 bss->ie_len = res->ie_len; 546 bss->beacon_ie_len = res->beacon_ie_len; 547 } 548 dl_list_add(prev, &bss->list_id); 549 } 550 if (changes & WPA_BSS_IES_CHANGED_FLAG) 551 wpa_bss_set_hessid(bss); 552 dl_list_add_tail(&wpa_s->bss, &bss->list); 553 554 notify_bss_changes(wpa_s, changes, bss); 555 556 return bss; 557 } 558 559 560 /** 561 * wpa_bss_update_start - Start a BSS table update from scan results 562 * @wpa_s: Pointer to wpa_supplicant data 563 * 564 * This function is called at the start of each BSS table update round for new 565 * scan results. The actual scan result entries are indicated with calls to 566 * wpa_bss_update_scan_res() and the update round is finished with a call to 567 * wpa_bss_update_end(). 568 */ 569 void wpa_bss_update_start(struct wpa_supplicant *wpa_s) 570 { 571 wpa_s->bss_update_idx++; 572 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Start scan result update %u", 573 wpa_s->bss_update_idx); 574 wpa_s->last_scan_res_used = 0; 575 } 576 577 578 /** 579 * wpa_bss_update_scan_res - Update a BSS table entry based on a scan result 580 * @wpa_s: Pointer to wpa_supplicant data 581 * @res: Scan result 582 * @fetch_time: Time when the result was fetched from the driver 583 * 584 * This function updates a BSS table entry (or adds one) based on a scan result. 585 * This is called separately for each scan result between the calls to 586 * wpa_bss_update_start() and wpa_bss_update_end(). 587 */ 588 void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s, 589 struct wpa_scan_res *res, 590 struct os_reltime *fetch_time) 591 { 592 const u8 *ssid, *p2p; 593 struct wpa_bss *bss; 594 595 if (wpa_s->conf->ignore_old_scan_res) { 596 struct os_reltime update; 597 calculate_update_time(fetch_time, res->age, &update); 598 if (os_reltime_before(&update, &wpa_s->scan_trigger_time)) { 599 struct os_reltime age; 600 os_reltime_sub(&wpa_s->scan_trigger_time, &update, 601 &age); 602 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Ignore driver BSS " 603 "table entry that is %u.%06u seconds older " 604 "than our scan trigger", 605 (unsigned int) age.sec, 606 (unsigned int) age.usec); 607 return; 608 } 609 } 610 611 ssid = wpa_scan_get_ie(res, WLAN_EID_SSID); 612 if (ssid == NULL) { 613 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: No SSID IE included for " 614 MACSTR, MAC2STR(res->bssid)); 615 return; 616 } 617 if (ssid[1] > 32) { 618 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Too long SSID IE included for " 619 MACSTR, MAC2STR(res->bssid)); 620 return; 621 } 622 623 p2p = wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE); 624 #ifdef CONFIG_P2P 625 if (p2p == NULL && 626 wpa_s->p2p_group_interface != NOT_P2P_GROUP_INTERFACE) { 627 /* 628 * If it's a P2P specific interface, then don't update 629 * the scan result without a P2P IE. 630 */ 631 wpa_printf(MSG_DEBUG, "BSS: No P2P IE - skipping BSS " MACSTR 632 " update for P2P interface", MAC2STR(res->bssid)); 633 return; 634 } 635 #endif /* CONFIG_P2P */ 636 if (p2p && ssid[1] == P2P_WILDCARD_SSID_LEN && 637 os_memcmp(ssid + 2, P2P_WILDCARD_SSID, P2P_WILDCARD_SSID_LEN) == 0) 638 return; /* Skip P2P listen discovery results here */ 639 640 /* TODO: add option for ignoring BSSes we are not interested in 641 * (to save memory) */ 642 bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]); 643 if (bss == NULL) 644 bss = wpa_bss_add(wpa_s, ssid + 2, ssid[1], res, fetch_time); 645 else { 646 bss = wpa_bss_update(wpa_s, bss, res, fetch_time); 647 if (wpa_s->last_scan_res) { 648 unsigned int i; 649 for (i = 0; i < wpa_s->last_scan_res_used; i++) { 650 if (bss == wpa_s->last_scan_res[i]) { 651 /* Already in the list */ 652 return; 653 } 654 } 655 } 656 } 657 658 if (bss == NULL) 659 return; 660 if (wpa_s->last_scan_res_used >= wpa_s->last_scan_res_size) { 661 struct wpa_bss **n; 662 unsigned int siz; 663 if (wpa_s->last_scan_res_size == 0) 664 siz = 32; 665 else 666 siz = wpa_s->last_scan_res_size * 2; 667 n = os_realloc_array(wpa_s->last_scan_res, siz, 668 sizeof(struct wpa_bss *)); 669 if (n == NULL) 670 return; 671 wpa_s->last_scan_res = n; 672 wpa_s->last_scan_res_size = siz; 673 } 674 675 wpa_s->last_scan_res[wpa_s->last_scan_res_used++] = bss; 676 } 677 678 679 static int wpa_bss_included_in_scan(const struct wpa_bss *bss, 680 const struct scan_info *info) 681 { 682 int found; 683 size_t i; 684 685 if (info == NULL) 686 return 1; 687 688 if (info->num_freqs) { 689 found = 0; 690 for (i = 0; i < info->num_freqs; i++) { 691 if (bss->freq == info->freqs[i]) { 692 found = 1; 693 break; 694 } 695 } 696 if (!found) 697 return 0; 698 } 699 700 if (info->num_ssids) { 701 found = 0; 702 for (i = 0; i < info->num_ssids; i++) { 703 const struct wpa_driver_scan_ssid *s = &info->ssids[i]; 704 if ((s->ssid == NULL || s->ssid_len == 0) || 705 (s->ssid_len == bss->ssid_len && 706 os_memcmp(s->ssid, bss->ssid, bss->ssid_len) == 707 0)) { 708 found = 1; 709 break; 710 } 711 } 712 if (!found) 713 return 0; 714 } 715 716 return 1; 717 } 718 719 720 /** 721 * wpa_bss_update_end - End a BSS table update from scan results 722 * @wpa_s: Pointer to wpa_supplicant data 723 * @info: Information about scan parameters 724 * @new_scan: Whether this update round was based on a new scan 725 * 726 * This function is called at the end of each BSS table update round for new 727 * scan results. The start of the update was indicated with a call to 728 * wpa_bss_update_start(). 729 */ 730 void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info, 731 int new_scan) 732 { 733 struct wpa_bss *bss, *n; 734 735 os_get_reltime(&wpa_s->last_scan); 736 if (!new_scan) 737 return; /* do not expire entries without new scan */ 738 739 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) { 740 if (wpa_bss_in_use(wpa_s, bss)) 741 continue; 742 if (!wpa_bss_included_in_scan(bss, info)) 743 continue; /* expire only BSSes that were scanned */ 744 if (bss->last_update_idx < wpa_s->bss_update_idx) 745 bss->scan_miss_count++; 746 if (bss->scan_miss_count >= 747 wpa_s->conf->bss_expiration_scan_count) { 748 wpa_bss_remove(wpa_s, bss, "no match in scan"); 749 } 750 } 751 752 wpa_printf(MSG_DEBUG, "BSS: last_scan_res_used=%u/%u", 753 wpa_s->last_scan_res_used, wpa_s->last_scan_res_size); 754 } 755 756 757 /** 758 * wpa_bss_flush_by_age - Flush old BSS entries 759 * @wpa_s: Pointer to wpa_supplicant data 760 * @age: Maximum entry age in seconds 761 * 762 * Remove BSS entries that have not been updated during the last @age seconds. 763 */ 764 void wpa_bss_flush_by_age(struct wpa_supplicant *wpa_s, int age) 765 { 766 struct wpa_bss *bss, *n; 767 struct os_reltime t; 768 769 if (dl_list_empty(&wpa_s->bss)) 770 return; 771 772 os_get_reltime(&t); 773 t.sec -= age; 774 775 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) { 776 if (wpa_bss_in_use(wpa_s, bss)) 777 continue; 778 779 if (os_reltime_before(&bss->last_update, &t)) { 780 wpa_bss_remove(wpa_s, bss, __func__); 781 } else 782 break; 783 } 784 } 785 786 787 static void wpa_bss_timeout(void *eloop_ctx, void *timeout_ctx) 788 { 789 struct wpa_supplicant *wpa_s = eloop_ctx; 790 791 wpa_bss_flush_by_age(wpa_s, wpa_s->conf->bss_expiration_age); 792 eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0, 793 wpa_bss_timeout, wpa_s, NULL); 794 } 795 796 797 /** 798 * wpa_bss_init - Initialize BSS table 799 * @wpa_s: Pointer to wpa_supplicant data 800 * Returns: 0 on success, -1 on failure 801 * 802 * This prepares BSS table lists and timer for periodic updates. The BSS table 803 * is deinitialized with wpa_bss_deinit() once not needed anymore. 804 */ 805 int wpa_bss_init(struct wpa_supplicant *wpa_s) 806 { 807 dl_list_init(&wpa_s->bss); 808 dl_list_init(&wpa_s->bss_id); 809 eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0, 810 wpa_bss_timeout, wpa_s, NULL); 811 return 0; 812 } 813 814 815 /** 816 * wpa_bss_flush - Flush all unused BSS entries 817 * @wpa_s: Pointer to wpa_supplicant data 818 */ 819 void wpa_bss_flush(struct wpa_supplicant *wpa_s) 820 { 821 struct wpa_bss *bss, *n; 822 823 wpa_s->clear_driver_scan_cache = 1; 824 825 if (wpa_s->bss.next == NULL) 826 return; /* BSS table not yet initialized */ 827 828 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) { 829 if (wpa_bss_in_use(wpa_s, bss)) 830 continue; 831 wpa_bss_remove(wpa_s, bss, __func__); 832 } 833 } 834 835 836 /** 837 * wpa_bss_deinit - Deinitialize BSS table 838 * @wpa_s: Pointer to wpa_supplicant data 839 */ 840 void wpa_bss_deinit(struct wpa_supplicant *wpa_s) 841 { 842 eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL); 843 wpa_bss_flush(wpa_s); 844 } 845 846 847 /** 848 * wpa_bss_get_bssid - Fetch a BSS table entry based on BSSID 849 * @wpa_s: Pointer to wpa_supplicant data 850 * @bssid: BSSID 851 * Returns: Pointer to the BSS entry or %NULL if not found 852 */ 853 struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s, 854 const u8 *bssid) 855 { 856 struct wpa_bss *bss; 857 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid)) 858 return NULL; 859 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) { 860 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0) 861 return bss; 862 } 863 return NULL; 864 } 865 866 867 /** 868 * wpa_bss_get_bssid_latest - Fetch the latest BSS table entry based on BSSID 869 * @wpa_s: Pointer to wpa_supplicant data 870 * @bssid: BSSID 871 * Returns: Pointer to the BSS entry or %NULL if not found 872 * 873 * This function is like wpa_bss_get_bssid(), but full BSS table is iterated to 874 * find the entry that has the most recent update. This can help in finding the 875 * correct entry in cases where the SSID of the AP may have changed recently 876 * (e.g., in WPS reconfiguration cases). 877 */ 878 struct wpa_bss * wpa_bss_get_bssid_latest(struct wpa_supplicant *wpa_s, 879 const u8 *bssid) 880 { 881 struct wpa_bss *bss, *found = NULL; 882 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid)) 883 return NULL; 884 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) { 885 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) != 0) 886 continue; 887 if (found == NULL || 888 os_reltime_before(&found->last_update, &bss->last_update)) 889 found = bss; 890 } 891 return found; 892 } 893 894 895 #ifdef CONFIG_P2P 896 /** 897 * wpa_bss_get_p2p_dev_addr - Fetch a BSS table entry based on P2P Device Addr 898 * @wpa_s: Pointer to wpa_supplicant data 899 * @dev_addr: P2P Device Address of the GO 900 * Returns: Pointer to the BSS entry or %NULL if not found 901 */ 902 struct wpa_bss * wpa_bss_get_p2p_dev_addr(struct wpa_supplicant *wpa_s, 903 const u8 *dev_addr) 904 { 905 struct wpa_bss *bss; 906 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) { 907 u8 addr[ETH_ALEN]; 908 if (p2p_parse_dev_addr((const u8 *) (bss + 1), bss->ie_len, 909 addr) == 0 && 910 os_memcmp(addr, dev_addr, ETH_ALEN) == 0) 911 return bss; 912 } 913 return NULL; 914 } 915 #endif /* CONFIG_P2P */ 916 917 918 /** 919 * wpa_bss_get_id - Fetch a BSS table entry based on identifier 920 * @wpa_s: Pointer to wpa_supplicant data 921 * @id: Unique identifier (struct wpa_bss::id) assigned for the entry 922 * Returns: Pointer to the BSS entry or %NULL if not found 923 */ 924 struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id) 925 { 926 struct wpa_bss *bss; 927 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 928 if (bss->id == id) 929 return bss; 930 } 931 return NULL; 932 } 933 934 935 /** 936 * wpa_bss_get_id_range - Fetch a BSS table entry based on identifier range 937 * @wpa_s: Pointer to wpa_supplicant data 938 * @idf: Smallest allowed identifier assigned for the entry 939 * @idf: Largest allowed identifier assigned for the entry 940 * Returns: Pointer to the BSS entry or %NULL if not found 941 * 942 * This function is similar to wpa_bss_get_id() but allows a BSS entry with the 943 * smallest id value to be fetched within the specified range without the 944 * caller having to know the exact id. 945 */ 946 struct wpa_bss * wpa_bss_get_id_range(struct wpa_supplicant *wpa_s, 947 unsigned int idf, unsigned int idl) 948 { 949 struct wpa_bss *bss; 950 dl_list_for_each(bss, &wpa_s->bss_id, struct wpa_bss, list_id) { 951 if (bss->id >= idf && bss->id <= idl) 952 return bss; 953 } 954 return NULL; 955 } 956 957 958 /** 959 * wpa_bss_get_ie - Fetch a specified information element from a BSS entry 960 * @bss: BSS table entry 961 * @ie: Information element identitifier (WLAN_EID_*) 962 * Returns: Pointer to the information element (id field) or %NULL if not found 963 * 964 * This function returns the first matching information element in the BSS 965 * entry. 966 */ 967 const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie) 968 { 969 const u8 *end, *pos; 970 971 pos = (const u8 *) (bss + 1); 972 end = pos + bss->ie_len; 973 974 while (pos + 1 < end) { 975 if (pos + 2 + pos[1] > end) 976 break; 977 if (pos[0] == ie) 978 return pos; 979 pos += 2 + pos[1]; 980 } 981 982 return NULL; 983 } 984 985 986 /** 987 * wpa_bss_get_vendor_ie - Fetch a vendor information element from a BSS entry 988 * @bss: BSS table entry 989 * @vendor_type: Vendor type (four octets starting the IE payload) 990 * Returns: Pointer to the information element (id field) or %NULL if not found 991 * 992 * This function returns the first matching information element in the BSS 993 * entry. 994 */ 995 const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type) 996 { 997 const u8 *end, *pos; 998 999 pos = (const u8 *) (bss + 1); 1000 end = pos + bss->ie_len; 1001 1002 while (pos + 1 < end) { 1003 if (pos + 2 + pos[1] > end) 1004 break; 1005 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 1006 vendor_type == WPA_GET_BE32(&pos[2])) 1007 return pos; 1008 pos += 2 + pos[1]; 1009 } 1010 1011 return NULL; 1012 } 1013 1014 1015 /** 1016 * wpa_bss_get_vendor_ie_beacon - Fetch a vendor information from a BSS entry 1017 * @bss: BSS table entry 1018 * @vendor_type: Vendor type (four octets starting the IE payload) 1019 * Returns: Pointer to the information element (id field) or %NULL if not found 1020 * 1021 * This function returns the first matching information element in the BSS 1022 * entry. 1023 * 1024 * This function is like wpa_bss_get_vendor_ie(), but uses IE buffer only 1025 * from Beacon frames instead of either Beacon or Probe Response frames. 1026 */ 1027 const u8 * wpa_bss_get_vendor_ie_beacon(const struct wpa_bss *bss, 1028 u32 vendor_type) 1029 { 1030 const u8 *end, *pos; 1031 1032 if (bss->beacon_ie_len == 0) 1033 return NULL; 1034 1035 pos = (const u8 *) (bss + 1); 1036 pos += bss->ie_len; 1037 end = pos + bss->beacon_ie_len; 1038 1039 while (pos + 1 < end) { 1040 if (pos + 2 + pos[1] > end) 1041 break; 1042 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 1043 vendor_type == WPA_GET_BE32(&pos[2])) 1044 return pos; 1045 pos += 2 + pos[1]; 1046 } 1047 1048 return NULL; 1049 } 1050 1051 1052 /** 1053 * wpa_bss_get_vendor_ie_multi - Fetch vendor IE data from a BSS entry 1054 * @bss: BSS table entry 1055 * @vendor_type: Vendor type (four octets starting the IE payload) 1056 * Returns: Pointer to the information element payload or %NULL if not found 1057 * 1058 * This function returns concatenated payload of possibly fragmented vendor 1059 * specific information elements in the BSS entry. The caller is responsible for 1060 * freeing the returned buffer. 1061 */ 1062 struct wpabuf * wpa_bss_get_vendor_ie_multi(const struct wpa_bss *bss, 1063 u32 vendor_type) 1064 { 1065 struct wpabuf *buf; 1066 const u8 *end, *pos; 1067 1068 buf = wpabuf_alloc(bss->ie_len); 1069 if (buf == NULL) 1070 return NULL; 1071 1072 pos = (const u8 *) (bss + 1); 1073 end = pos + bss->ie_len; 1074 1075 while (pos + 1 < end) { 1076 if (pos + 2 + pos[1] > end) 1077 break; 1078 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 1079 vendor_type == WPA_GET_BE32(&pos[2])) 1080 wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4); 1081 pos += 2 + pos[1]; 1082 } 1083 1084 if (wpabuf_len(buf) == 0) { 1085 wpabuf_free(buf); 1086 buf = NULL; 1087 } 1088 1089 return buf; 1090 } 1091 1092 1093 /** 1094 * wpa_bss_get_vendor_ie_multi_beacon - Fetch vendor IE data from a BSS entry 1095 * @bss: BSS table entry 1096 * @vendor_type: Vendor type (four octets starting the IE payload) 1097 * Returns: Pointer to the information element payload or %NULL if not found 1098 * 1099 * This function returns concatenated payload of possibly fragmented vendor 1100 * specific information elements in the BSS entry. The caller is responsible for 1101 * freeing the returned buffer. 1102 * 1103 * This function is like wpa_bss_get_vendor_ie_multi(), but uses IE buffer only 1104 * from Beacon frames instead of either Beacon or Probe Response frames. 1105 */ 1106 struct wpabuf * wpa_bss_get_vendor_ie_multi_beacon(const struct wpa_bss *bss, 1107 u32 vendor_type) 1108 { 1109 struct wpabuf *buf; 1110 const u8 *end, *pos; 1111 1112 buf = wpabuf_alloc(bss->beacon_ie_len); 1113 if (buf == NULL) 1114 return NULL; 1115 1116 pos = (const u8 *) (bss + 1); 1117 pos += bss->ie_len; 1118 end = pos + bss->beacon_ie_len; 1119 1120 while (pos + 1 < end) { 1121 if (pos + 2 + pos[1] > end) 1122 break; 1123 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 1124 vendor_type == WPA_GET_BE32(&pos[2])) 1125 wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4); 1126 pos += 2 + pos[1]; 1127 } 1128 1129 if (wpabuf_len(buf) == 0) { 1130 wpabuf_free(buf); 1131 buf = NULL; 1132 } 1133 1134 return buf; 1135 } 1136 1137 1138 /** 1139 * wpa_bss_get_max_rate - Get maximum legacy TX rate supported in a BSS 1140 * @bss: BSS table entry 1141 * Returns: Maximum legacy rate in units of 500 kbps 1142 */ 1143 int wpa_bss_get_max_rate(const struct wpa_bss *bss) 1144 { 1145 int rate = 0; 1146 const u8 *ie; 1147 int i; 1148 1149 ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES); 1150 for (i = 0; ie && i < ie[1]; i++) { 1151 if ((ie[i + 2] & 0x7f) > rate) 1152 rate = ie[i + 2] & 0x7f; 1153 } 1154 1155 ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES); 1156 for (i = 0; ie && i < ie[1]; i++) { 1157 if ((ie[i + 2] & 0x7f) > rate) 1158 rate = ie[i + 2] & 0x7f; 1159 } 1160 1161 return rate; 1162 } 1163 1164 1165 /** 1166 * wpa_bss_get_bit_rates - Get legacy TX rates supported in a BSS 1167 * @bss: BSS table entry 1168 * @rates: Buffer for returning a pointer to the rates list (units of 500 kbps) 1169 * Returns: number of legacy TX rates or -1 on failure 1170 * 1171 * The caller is responsible for freeing the returned buffer with os_free() in 1172 * case of success. 1173 */ 1174 int wpa_bss_get_bit_rates(const struct wpa_bss *bss, u8 **rates) 1175 { 1176 const u8 *ie, *ie2; 1177 int i, j; 1178 unsigned int len; 1179 u8 *r; 1180 1181 ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES); 1182 ie2 = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES); 1183 1184 len = (ie ? ie[1] : 0) + (ie2 ? ie2[1] : 0); 1185 1186 r = os_malloc(len); 1187 if (!r) 1188 return -1; 1189 1190 for (i = 0; ie && i < ie[1]; i++) 1191 r[i] = ie[i + 2] & 0x7f; 1192 1193 for (j = 0; ie2 && j < ie2[1]; j++) 1194 r[i + j] = ie2[j + 2] & 0x7f; 1195 1196 *rates = r; 1197 return len; 1198 } 1199