1 /* 2 * BSS table 3 * Copyright (c) 2009-2015, Jouni Malinen <j (at) 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(capability_list); 89 ANQP_DUP(venue_name); 90 ANQP_DUP(network_auth_type); 91 ANQP_DUP(roaming_consortium); 92 ANQP_DUP(ip_addr_type_availability); 93 ANQP_DUP(nai_realm); 94 ANQP_DUP(anqp_3gpp); 95 ANQP_DUP(domain_name); 96 #endif /* CONFIG_INTERWORKING */ 97 #ifdef CONFIG_HS20 98 ANQP_DUP(hs20_capability_list); 99 ANQP_DUP(hs20_operator_friendly_name); 100 ANQP_DUP(hs20_wan_metrics); 101 ANQP_DUP(hs20_connection_capability); 102 ANQP_DUP(hs20_operating_class); 103 ANQP_DUP(hs20_osu_providers_list); 104 #endif /* CONFIG_HS20 */ 105 #undef ANQP_DUP 106 107 return n; 108 } 109 110 111 /** 112 * wpa_bss_anqp_unshare_alloc - Unshare ANQP data (if shared) in a BSS entry 113 * @bss: BSS entry 114 * Returns: 0 on success, -1 on failure 115 * 116 * This function ensures the specific BSS entry has an ANQP data structure that 117 * is not shared with any other BSS entry. 118 */ 119 int wpa_bss_anqp_unshare_alloc(struct wpa_bss *bss) 120 { 121 struct wpa_bss_anqp *anqp; 122 123 if (bss->anqp && bss->anqp->users > 1) { 124 /* allocated, but shared - clone an unshared copy */ 125 anqp = wpa_bss_anqp_clone(bss->anqp); 126 if (anqp == NULL) 127 return -1; 128 anqp->users = 1; 129 bss->anqp->users--; 130 bss->anqp = anqp; 131 return 0; 132 } 133 134 if (bss->anqp) 135 return 0; /* already allocated and not shared */ 136 137 /* not allocated - allocate a new storage area */ 138 bss->anqp = wpa_bss_anqp_alloc(); 139 return bss->anqp ? 0 : -1; 140 } 141 142 143 /** 144 * wpa_bss_anqp_free - Free an ANQP data structure 145 * @anqp: ANQP data structure from wpa_bss_anqp_alloc() or wpa_bss_anqp_clone() 146 */ 147 static void wpa_bss_anqp_free(struct wpa_bss_anqp *anqp) 148 { 149 if (anqp == NULL) 150 return; 151 152 anqp->users--; 153 if (anqp->users > 0) { 154 /* Another BSS entry holds a pointer to this ANQP info */ 155 return; 156 } 157 158 #ifdef CONFIG_INTERWORKING 159 wpabuf_free(anqp->capability_list); 160 wpabuf_free(anqp->venue_name); 161 wpabuf_free(anqp->network_auth_type); 162 wpabuf_free(anqp->roaming_consortium); 163 wpabuf_free(anqp->ip_addr_type_availability); 164 wpabuf_free(anqp->nai_realm); 165 wpabuf_free(anqp->anqp_3gpp); 166 wpabuf_free(anqp->domain_name); 167 #endif /* CONFIG_INTERWORKING */ 168 #ifdef CONFIG_HS20 169 wpabuf_free(anqp->hs20_capability_list); 170 wpabuf_free(anqp->hs20_operator_friendly_name); 171 wpabuf_free(anqp->hs20_wan_metrics); 172 wpabuf_free(anqp->hs20_connection_capability); 173 wpabuf_free(anqp->hs20_operating_class); 174 wpabuf_free(anqp->hs20_osu_providers_list); 175 #endif /* CONFIG_HS20 */ 176 177 os_free(anqp); 178 } 179 180 181 static void wpa_bss_update_pending_connect(struct wpa_supplicant *wpa_s, 182 struct wpa_bss *old_bss, 183 struct wpa_bss *new_bss) 184 { 185 struct wpa_radio_work *work; 186 struct wpa_connect_work *cwork; 187 188 work = radio_work_pending(wpa_s, "sme-connect"); 189 if (!work) 190 work = radio_work_pending(wpa_s, "connect"); 191 if (!work) 192 return; 193 194 cwork = work->ctx; 195 if (cwork->bss != old_bss) 196 return; 197 198 wpa_printf(MSG_DEBUG, 199 "Update BSS pointer for the pending connect radio work"); 200 cwork->bss = new_bss; 201 if (!new_bss) 202 cwork->bss_removed = 1; 203 } 204 205 206 static void wpa_bss_remove(struct wpa_supplicant *wpa_s, struct wpa_bss *bss, 207 const char *reason) 208 { 209 if (wpa_s->last_scan_res) { 210 unsigned int i; 211 for (i = 0; i < wpa_s->last_scan_res_used; i++) { 212 if (wpa_s->last_scan_res[i] == bss) { 213 os_memmove(&wpa_s->last_scan_res[i], 214 &wpa_s->last_scan_res[i + 1], 215 (wpa_s->last_scan_res_used - i - 1) 216 * sizeof(struct wpa_bss *)); 217 wpa_s->last_scan_res_used--; 218 break; 219 } 220 } 221 } 222 wpa_bss_update_pending_connect(wpa_s, bss, NULL); 223 dl_list_del(&bss->list); 224 dl_list_del(&bss->list_id); 225 wpa_s->num_bss--; 226 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR 227 " SSID '%s' due to %s", bss->id, MAC2STR(bss->bssid), 228 wpa_ssid_txt(bss->ssid, bss->ssid_len), reason); 229 wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id); 230 wpa_bss_anqp_free(bss->anqp); 231 os_free(bss); 232 } 233 234 235 /** 236 * wpa_bss_get - Fetch a BSS table entry based on BSSID and SSID 237 * @wpa_s: Pointer to wpa_supplicant data 238 * @bssid: BSSID 239 * @ssid: SSID 240 * @ssid_len: Length of @ssid 241 * Returns: Pointer to the BSS entry or %NULL if not found 242 */ 243 struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid, 244 const u8 *ssid, size_t ssid_len) 245 { 246 struct wpa_bss *bss; 247 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid)) 248 return NULL; 249 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 250 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 && 251 bss->ssid_len == ssid_len && 252 os_memcmp(bss->ssid, ssid, ssid_len) == 0) 253 return bss; 254 } 255 return NULL; 256 } 257 258 259 static void calculate_update_time(const struct os_reltime *fetch_time, 260 unsigned int age_ms, 261 struct os_reltime *update_time) 262 { 263 os_time_t usec; 264 265 update_time->sec = fetch_time->sec; 266 update_time->usec = fetch_time->usec; 267 update_time->sec -= age_ms / 1000; 268 usec = (age_ms % 1000) * 1000; 269 if (update_time->usec < usec) { 270 update_time->sec--; 271 update_time->usec += 1000000; 272 } 273 update_time->usec -= usec; 274 } 275 276 277 static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src, 278 struct os_reltime *fetch_time) 279 { 280 dst->flags = src->flags; 281 os_memcpy(dst->bssid, src->bssid, ETH_ALEN); 282 dst->freq = src->freq; 283 dst->beacon_int = src->beacon_int; 284 dst->caps = src->caps; 285 dst->qual = src->qual; 286 dst->noise = src->noise; 287 dst->level = src->level; 288 dst->tsf = src->tsf; 289 dst->est_throughput = src->est_throughput; 290 dst->snr = src->snr; 291 292 calculate_update_time(fetch_time, src->age, &dst->last_update); 293 } 294 295 296 static int wpa_bss_known(struct wpa_supplicant *wpa_s, struct wpa_bss *bss) 297 { 298 struct wpa_ssid *ssid; 299 300 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) { 301 if (ssid->ssid == NULL || ssid->ssid_len == 0) 302 continue; 303 if (ssid->ssid_len == bss->ssid_len && 304 os_memcmp(ssid->ssid, bss->ssid, ssid->ssid_len) == 0) 305 return 1; 306 } 307 308 return 0; 309 } 310 311 312 static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss) 313 { 314 return bss == wpa_s->current_bss || 315 (!is_zero_ether_addr(bss->bssid) && 316 (os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 || 317 os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0)); 318 } 319 320 321 static int wpa_bss_remove_oldest_unknown(struct wpa_supplicant *wpa_s) 322 { 323 struct wpa_bss *bss; 324 325 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 326 if (!wpa_bss_known(wpa_s, bss)) { 327 wpa_bss_remove(wpa_s, bss, __func__); 328 return 0; 329 } 330 } 331 332 return -1; 333 } 334 335 336 static int wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s) 337 { 338 struct wpa_bss *bss; 339 340 /* 341 * Remove the oldest entry that does not match with any configured 342 * network. 343 */ 344 if (wpa_bss_remove_oldest_unknown(wpa_s) == 0) 345 return 0; 346 347 /* 348 * Remove the oldest entry that isn't currently in use. 349 */ 350 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 351 if (!wpa_bss_in_use(wpa_s, bss)) { 352 wpa_bss_remove(wpa_s, bss, __func__); 353 return 0; 354 } 355 } 356 357 return -1; 358 } 359 360 361 static struct wpa_bss * wpa_bss_add(struct wpa_supplicant *wpa_s, 362 const u8 *ssid, size_t ssid_len, 363 struct wpa_scan_res *res, 364 struct os_reltime *fetch_time) 365 { 366 struct wpa_bss *bss; 367 368 bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len); 369 if (bss == NULL) 370 return NULL; 371 bss->id = wpa_s->bss_next_id++; 372 bss->last_update_idx = wpa_s->bss_update_idx; 373 wpa_bss_copy_res(bss, res, fetch_time); 374 os_memcpy(bss->ssid, ssid, ssid_len); 375 bss->ssid_len = ssid_len; 376 bss->ie_len = res->ie_len; 377 bss->beacon_ie_len = res->beacon_ie_len; 378 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len); 379 wpa_bss_set_hessid(bss); 380 381 if (wpa_s->num_bss + 1 > wpa_s->conf->bss_max_count && 382 wpa_bss_remove_oldest(wpa_s) != 0) { 383 wpa_printf(MSG_ERROR, "Increasing the MAX BSS count to %d " 384 "because all BSSes are in use. We should normally " 385 "not get here!", (int) wpa_s->num_bss + 1); 386 wpa_s->conf->bss_max_count = wpa_s->num_bss + 1; 387 } 388 389 dl_list_add_tail(&wpa_s->bss, &bss->list); 390 dl_list_add_tail(&wpa_s->bss_id, &bss->list_id); 391 wpa_s->num_bss++; 392 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR 393 " SSID '%s'", 394 bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len)); 395 wpas_notify_bss_added(wpa_s, bss->bssid, bss->id); 396 return bss; 397 } 398 399 400 static int are_ies_equal(const struct wpa_bss *old, 401 const struct wpa_scan_res *new_res, u32 ie) 402 { 403 const u8 *old_ie, *new_ie; 404 struct wpabuf *old_ie_buff = NULL; 405 struct wpabuf *new_ie_buff = NULL; 406 int new_ie_len, old_ie_len, ret, is_multi; 407 408 switch (ie) { 409 case WPA_IE_VENDOR_TYPE: 410 old_ie = wpa_bss_get_vendor_ie(old, ie); 411 new_ie = wpa_scan_get_vendor_ie(new_res, ie); 412 is_multi = 0; 413 break; 414 case WPS_IE_VENDOR_TYPE: 415 old_ie_buff = wpa_bss_get_vendor_ie_multi(old, ie); 416 new_ie_buff = wpa_scan_get_vendor_ie_multi(new_res, ie); 417 is_multi = 1; 418 break; 419 case WLAN_EID_RSN: 420 case WLAN_EID_SUPP_RATES: 421 case WLAN_EID_EXT_SUPP_RATES: 422 old_ie = wpa_bss_get_ie(old, ie); 423 new_ie = wpa_scan_get_ie(new_res, ie); 424 is_multi = 0; 425 break; 426 default: 427 wpa_printf(MSG_DEBUG, "bss: %s: cannot compare IEs", __func__); 428 return 0; 429 } 430 431 if (is_multi) { 432 /* in case of multiple IEs stored in buffer */ 433 old_ie = old_ie_buff ? wpabuf_head_u8(old_ie_buff) : NULL; 434 new_ie = new_ie_buff ? wpabuf_head_u8(new_ie_buff) : NULL; 435 old_ie_len = old_ie_buff ? wpabuf_len(old_ie_buff) : 0; 436 new_ie_len = new_ie_buff ? wpabuf_len(new_ie_buff) : 0; 437 } else { 438 /* in case of single IE */ 439 old_ie_len = old_ie ? old_ie[1] + 2 : 0; 440 new_ie_len = new_ie ? new_ie[1] + 2 : 0; 441 } 442 443 if (!old_ie || !new_ie) 444 ret = !old_ie && !new_ie; 445 else 446 ret = (old_ie_len == new_ie_len && 447 os_memcmp(old_ie, new_ie, old_ie_len) == 0); 448 449 wpabuf_free(old_ie_buff); 450 wpabuf_free(new_ie_buff); 451 452 return ret; 453 } 454 455 456 static u32 wpa_bss_compare_res(const struct wpa_bss *old, 457 const struct wpa_scan_res *new_res) 458 { 459 u32 changes = 0; 460 int caps_diff = old->caps ^ new_res->caps; 461 462 if (old->freq != new_res->freq) 463 changes |= WPA_BSS_FREQ_CHANGED_FLAG; 464 465 if (old->level != new_res->level) 466 changes |= WPA_BSS_SIGNAL_CHANGED_FLAG; 467 468 if (caps_diff & IEEE80211_CAP_PRIVACY) 469 changes |= WPA_BSS_PRIVACY_CHANGED_FLAG; 470 471 if (caps_diff & IEEE80211_CAP_IBSS) 472 changes |= WPA_BSS_MODE_CHANGED_FLAG; 473 474 if (old->ie_len == new_res->ie_len && 475 os_memcmp(old + 1, new_res + 1, old->ie_len) == 0) 476 return changes; 477 changes |= WPA_BSS_IES_CHANGED_FLAG; 478 479 if (!are_ies_equal(old, new_res, WPA_IE_VENDOR_TYPE)) 480 changes |= WPA_BSS_WPAIE_CHANGED_FLAG; 481 482 if (!are_ies_equal(old, new_res, WLAN_EID_RSN)) 483 changes |= WPA_BSS_RSNIE_CHANGED_FLAG; 484 485 if (!are_ies_equal(old, new_res, WPS_IE_VENDOR_TYPE)) 486 changes |= WPA_BSS_WPS_CHANGED_FLAG; 487 488 if (!are_ies_equal(old, new_res, WLAN_EID_SUPP_RATES) || 489 !are_ies_equal(old, new_res, WLAN_EID_EXT_SUPP_RATES)) 490 changes |= WPA_BSS_RATES_CHANGED_FLAG; 491 492 return changes; 493 } 494 495 496 static void notify_bss_changes(struct wpa_supplicant *wpa_s, u32 changes, 497 const struct wpa_bss *bss) 498 { 499 if (changes & WPA_BSS_FREQ_CHANGED_FLAG) 500 wpas_notify_bss_freq_changed(wpa_s, bss->id); 501 502 if (changes & WPA_BSS_SIGNAL_CHANGED_FLAG) 503 wpas_notify_bss_signal_changed(wpa_s, bss->id); 504 505 if (changes & WPA_BSS_PRIVACY_CHANGED_FLAG) 506 wpas_notify_bss_privacy_changed(wpa_s, bss->id); 507 508 if (changes & WPA_BSS_MODE_CHANGED_FLAG) 509 wpas_notify_bss_mode_changed(wpa_s, bss->id); 510 511 if (changes & WPA_BSS_WPAIE_CHANGED_FLAG) 512 wpas_notify_bss_wpaie_changed(wpa_s, bss->id); 513 514 if (changes & WPA_BSS_RSNIE_CHANGED_FLAG) 515 wpas_notify_bss_rsnie_changed(wpa_s, bss->id); 516 517 if (changes & WPA_BSS_WPS_CHANGED_FLAG) 518 wpas_notify_bss_wps_changed(wpa_s, bss->id); 519 520 if (changes & WPA_BSS_IES_CHANGED_FLAG) 521 wpas_notify_bss_ies_changed(wpa_s, bss->id); 522 523 if (changes & WPA_BSS_RATES_CHANGED_FLAG) 524 wpas_notify_bss_rates_changed(wpa_s, bss->id); 525 526 wpas_notify_bss_seen(wpa_s, bss->id); 527 } 528 529 530 static struct wpa_bss * 531 wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss, 532 struct wpa_scan_res *res, struct os_reltime *fetch_time) 533 { 534 u32 changes; 535 536 changes = wpa_bss_compare_res(bss, res); 537 bss->scan_miss_count = 0; 538 bss->last_update_idx = wpa_s->bss_update_idx; 539 wpa_bss_copy_res(bss, res, fetch_time); 540 /* Move the entry to the end of the list */ 541 dl_list_del(&bss->list); 542 #ifdef CONFIG_P2P 543 if (wpa_bss_get_vendor_ie(bss, P2P_IE_VENDOR_TYPE) && 544 !wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE)) { 545 /* 546 * This can happen when non-P2P station interface runs a scan 547 * without P2P IE in the Probe Request frame. P2P GO would reply 548 * to that with a Probe Response that does not include P2P IE. 549 * Do not update the IEs in this BSS entry to avoid such loss of 550 * information that may be needed for P2P operations to 551 * determine group information. 552 */ 553 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Do not update scan IEs for " 554 MACSTR " since that would remove P2P IE information", 555 MAC2STR(bss->bssid)); 556 } else 557 #endif /* CONFIG_P2P */ 558 if (bss->ie_len + bss->beacon_ie_len >= 559 res->ie_len + res->beacon_ie_len) { 560 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len); 561 bss->ie_len = res->ie_len; 562 bss->beacon_ie_len = res->beacon_ie_len; 563 } else { 564 struct wpa_bss *nbss; 565 struct dl_list *prev = bss->list_id.prev; 566 dl_list_del(&bss->list_id); 567 nbss = os_realloc(bss, sizeof(*bss) + res->ie_len + 568 res->beacon_ie_len); 569 if (nbss) { 570 unsigned int i; 571 for (i = 0; i < wpa_s->last_scan_res_used; i++) { 572 if (wpa_s->last_scan_res[i] == bss) { 573 wpa_s->last_scan_res[i] = nbss; 574 break; 575 } 576 } 577 if (wpa_s->current_bss == bss) 578 wpa_s->current_bss = nbss; 579 wpa_bss_update_pending_connect(wpa_s, bss, nbss); 580 bss = nbss; 581 os_memcpy(bss + 1, res + 1, 582 res->ie_len + res->beacon_ie_len); 583 bss->ie_len = res->ie_len; 584 bss->beacon_ie_len = res->beacon_ie_len; 585 } 586 dl_list_add(prev, &bss->list_id); 587 } 588 if (changes & WPA_BSS_IES_CHANGED_FLAG) 589 wpa_bss_set_hessid(bss); 590 dl_list_add_tail(&wpa_s->bss, &bss->list); 591 592 notify_bss_changes(wpa_s, changes, bss); 593 594 return bss; 595 } 596 597 598 /** 599 * wpa_bss_update_start - Start a BSS table update from scan results 600 * @wpa_s: Pointer to wpa_supplicant data 601 * 602 * This function is called at the start of each BSS table update round for new 603 * scan results. The actual scan result entries are indicated with calls to 604 * wpa_bss_update_scan_res() and the update round is finished with a call to 605 * wpa_bss_update_end(). 606 */ 607 void wpa_bss_update_start(struct wpa_supplicant *wpa_s) 608 { 609 wpa_s->bss_update_idx++; 610 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Start scan result update %u", 611 wpa_s->bss_update_idx); 612 wpa_s->last_scan_res_used = 0; 613 } 614 615 616 /** 617 * wpa_bss_update_scan_res - Update a BSS table entry based on a scan result 618 * @wpa_s: Pointer to wpa_supplicant data 619 * @res: Scan result 620 * @fetch_time: Time when the result was fetched from the driver 621 * 622 * This function updates a BSS table entry (or adds one) based on a scan result. 623 * This is called separately for each scan result between the calls to 624 * wpa_bss_update_start() and wpa_bss_update_end(). 625 */ 626 void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s, 627 struct wpa_scan_res *res, 628 struct os_reltime *fetch_time) 629 { 630 const u8 *ssid, *p2p, *mesh; 631 struct wpa_bss *bss; 632 633 if (wpa_s->conf->ignore_old_scan_res) { 634 struct os_reltime update; 635 calculate_update_time(fetch_time, res->age, &update); 636 if (os_reltime_before(&update, &wpa_s->scan_trigger_time)) { 637 struct os_reltime age; 638 os_reltime_sub(&wpa_s->scan_trigger_time, &update, 639 &age); 640 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Ignore driver BSS " 641 "table entry that is %u.%06u seconds older " 642 "than our scan trigger", 643 (unsigned int) age.sec, 644 (unsigned int) age.usec); 645 return; 646 } 647 } 648 649 ssid = wpa_scan_get_ie(res, WLAN_EID_SSID); 650 if (ssid == NULL) { 651 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: No SSID IE included for " 652 MACSTR, MAC2STR(res->bssid)); 653 return; 654 } 655 if (ssid[1] > SSID_MAX_LEN) { 656 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Too long SSID IE included for " 657 MACSTR, MAC2STR(res->bssid)); 658 return; 659 } 660 661 p2p = wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE); 662 #ifdef CONFIG_P2P 663 if (p2p == NULL && 664 wpa_s->p2p_group_interface != NOT_P2P_GROUP_INTERFACE) { 665 /* 666 * If it's a P2P specific interface, then don't update 667 * the scan result without a P2P IE. 668 */ 669 wpa_printf(MSG_DEBUG, "BSS: No P2P IE - skipping BSS " MACSTR 670 " update for P2P interface", MAC2STR(res->bssid)); 671 return; 672 } 673 #endif /* CONFIG_P2P */ 674 if (p2p && ssid[1] == P2P_WILDCARD_SSID_LEN && 675 os_memcmp(ssid + 2, P2P_WILDCARD_SSID, P2P_WILDCARD_SSID_LEN) == 0) 676 return; /* Skip P2P listen discovery results here */ 677 678 /* TODO: add option for ignoring BSSes we are not interested in 679 * (to save memory) */ 680 681 mesh = wpa_scan_get_ie(res, WLAN_EID_MESH_ID); 682 if (mesh && mesh[1] <= SSID_MAX_LEN) 683 ssid = mesh; 684 685 bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]); 686 if (bss == NULL) 687 bss = wpa_bss_add(wpa_s, ssid + 2, ssid[1], res, fetch_time); 688 else { 689 bss = wpa_bss_update(wpa_s, bss, res, fetch_time); 690 if (wpa_s->last_scan_res) { 691 unsigned int i; 692 for (i = 0; i < wpa_s->last_scan_res_used; i++) { 693 if (bss == wpa_s->last_scan_res[i]) { 694 /* Already in the list */ 695 return; 696 } 697 } 698 } 699 } 700 701 if (bss == NULL) 702 return; 703 if (wpa_s->last_scan_res_used >= wpa_s->last_scan_res_size) { 704 struct wpa_bss **n; 705 unsigned int siz; 706 if (wpa_s->last_scan_res_size == 0) 707 siz = 32; 708 else 709 siz = wpa_s->last_scan_res_size * 2; 710 n = os_realloc_array(wpa_s->last_scan_res, siz, 711 sizeof(struct wpa_bss *)); 712 if (n == NULL) 713 return; 714 wpa_s->last_scan_res = n; 715 wpa_s->last_scan_res_size = siz; 716 } 717 718 if (wpa_s->last_scan_res) 719 wpa_s->last_scan_res[wpa_s->last_scan_res_used++] = bss; 720 } 721 722 723 static int wpa_bss_included_in_scan(const struct wpa_bss *bss, 724 const struct scan_info *info) 725 { 726 int found; 727 size_t i; 728 729 if (info == NULL) 730 return 1; 731 732 if (info->num_freqs) { 733 found = 0; 734 for (i = 0; i < info->num_freqs; i++) { 735 if (bss->freq == info->freqs[i]) { 736 found = 1; 737 break; 738 } 739 } 740 if (!found) 741 return 0; 742 } 743 744 if (info->num_ssids) { 745 found = 0; 746 for (i = 0; i < info->num_ssids; i++) { 747 const struct wpa_driver_scan_ssid *s = &info->ssids[i]; 748 if ((s->ssid == NULL || s->ssid_len == 0) || 749 (s->ssid_len == bss->ssid_len && 750 os_memcmp(s->ssid, bss->ssid, bss->ssid_len) == 751 0)) { 752 found = 1; 753 break; 754 } 755 } 756 if (!found) 757 return 0; 758 } 759 760 return 1; 761 } 762 763 764 /** 765 * wpa_bss_update_end - End a BSS table update from scan results 766 * @wpa_s: Pointer to wpa_supplicant data 767 * @info: Information about scan parameters 768 * @new_scan: Whether this update round was based on a new scan 769 * 770 * This function is called at the end of each BSS table update round for new 771 * scan results. The start of the update was indicated with a call to 772 * wpa_bss_update_start(). 773 */ 774 void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info, 775 int new_scan) 776 { 777 struct wpa_bss *bss, *n; 778 779 os_get_reltime(&wpa_s->last_scan); 780 if (!new_scan) 781 return; /* do not expire entries without new scan */ 782 783 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) { 784 if (wpa_bss_in_use(wpa_s, bss)) 785 continue; 786 if (!wpa_bss_included_in_scan(bss, info)) 787 continue; /* expire only BSSes that were scanned */ 788 if (bss->last_update_idx < wpa_s->bss_update_idx) 789 bss->scan_miss_count++; 790 if (bss->scan_miss_count >= 791 wpa_s->conf->bss_expiration_scan_count) { 792 wpa_bss_remove(wpa_s, bss, "no match in scan"); 793 } 794 } 795 796 wpa_printf(MSG_DEBUG, "BSS: last_scan_res_used=%u/%u", 797 wpa_s->last_scan_res_used, wpa_s->last_scan_res_size); 798 } 799 800 801 /** 802 * wpa_bss_flush_by_age - Flush old BSS entries 803 * @wpa_s: Pointer to wpa_supplicant data 804 * @age: Maximum entry age in seconds 805 * 806 * Remove BSS entries that have not been updated during the last @age seconds. 807 */ 808 void wpa_bss_flush_by_age(struct wpa_supplicant *wpa_s, int age) 809 { 810 struct wpa_bss *bss, *n; 811 struct os_reltime t; 812 813 if (dl_list_empty(&wpa_s->bss)) 814 return; 815 816 os_get_reltime(&t); 817 t.sec -= age; 818 819 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) { 820 if (wpa_bss_in_use(wpa_s, bss)) 821 continue; 822 823 if (os_reltime_before(&bss->last_update, &t)) { 824 wpa_bss_remove(wpa_s, bss, __func__); 825 } else 826 break; 827 } 828 } 829 830 831 static void wpa_bss_timeout(void *eloop_ctx, void *timeout_ctx) 832 { 833 struct wpa_supplicant *wpa_s = eloop_ctx; 834 835 wpa_bss_flush_by_age(wpa_s, wpa_s->conf->bss_expiration_age); 836 eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0, 837 wpa_bss_timeout, wpa_s, NULL); 838 } 839 840 841 /** 842 * wpa_bss_init - Initialize BSS table 843 * @wpa_s: Pointer to wpa_supplicant data 844 * Returns: 0 on success, -1 on failure 845 * 846 * This prepares BSS table lists and timer for periodic updates. The BSS table 847 * is deinitialized with wpa_bss_deinit() once not needed anymore. 848 */ 849 int wpa_bss_init(struct wpa_supplicant *wpa_s) 850 { 851 dl_list_init(&wpa_s->bss); 852 dl_list_init(&wpa_s->bss_id); 853 eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0, 854 wpa_bss_timeout, wpa_s, NULL); 855 return 0; 856 } 857 858 859 /** 860 * wpa_bss_flush - Flush all unused BSS entries 861 * @wpa_s: Pointer to wpa_supplicant data 862 */ 863 void wpa_bss_flush(struct wpa_supplicant *wpa_s) 864 { 865 struct wpa_bss *bss, *n; 866 867 wpa_s->clear_driver_scan_cache = 1; 868 869 if (wpa_s->bss.next == NULL) 870 return; /* BSS table not yet initialized */ 871 872 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) { 873 if (wpa_bss_in_use(wpa_s, bss)) 874 continue; 875 wpa_bss_remove(wpa_s, bss, __func__); 876 } 877 } 878 879 880 /** 881 * wpa_bss_deinit - Deinitialize BSS table 882 * @wpa_s: Pointer to wpa_supplicant data 883 */ 884 void wpa_bss_deinit(struct wpa_supplicant *wpa_s) 885 { 886 eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL); 887 wpa_bss_flush(wpa_s); 888 } 889 890 891 /** 892 * wpa_bss_get_bssid - Fetch a BSS table entry based on BSSID 893 * @wpa_s: Pointer to wpa_supplicant data 894 * @bssid: BSSID 895 * Returns: Pointer to the BSS entry or %NULL if not found 896 */ 897 struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s, 898 const u8 *bssid) 899 { 900 struct wpa_bss *bss; 901 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid)) 902 return NULL; 903 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) { 904 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0) 905 return bss; 906 } 907 return NULL; 908 } 909 910 911 /** 912 * wpa_bss_get_bssid_latest - Fetch the latest BSS table entry based on BSSID 913 * @wpa_s: Pointer to wpa_supplicant data 914 * @bssid: BSSID 915 * Returns: Pointer to the BSS entry or %NULL if not found 916 * 917 * This function is like wpa_bss_get_bssid(), but full BSS table is iterated to 918 * find the entry that has the most recent update. This can help in finding the 919 * correct entry in cases where the SSID of the AP may have changed recently 920 * (e.g., in WPS reconfiguration cases). 921 */ 922 struct wpa_bss * wpa_bss_get_bssid_latest(struct wpa_supplicant *wpa_s, 923 const u8 *bssid) 924 { 925 struct wpa_bss *bss, *found = NULL; 926 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid)) 927 return NULL; 928 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) { 929 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) != 0) 930 continue; 931 if (found == NULL || 932 os_reltime_before(&found->last_update, &bss->last_update)) 933 found = bss; 934 } 935 return found; 936 } 937 938 939 #ifdef CONFIG_P2P 940 /** 941 * wpa_bss_get_p2p_dev_addr - Fetch a BSS table entry based on P2P Device Addr 942 * @wpa_s: Pointer to wpa_supplicant data 943 * @dev_addr: P2P Device Address of the GO 944 * Returns: Pointer to the BSS entry or %NULL if not found 945 */ 946 struct wpa_bss * wpa_bss_get_p2p_dev_addr(struct wpa_supplicant *wpa_s, 947 const u8 *dev_addr) 948 { 949 struct wpa_bss *bss; 950 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) { 951 u8 addr[ETH_ALEN]; 952 if (p2p_parse_dev_addr((const u8 *) (bss + 1), bss->ie_len, 953 addr) == 0 && 954 os_memcmp(addr, dev_addr, ETH_ALEN) == 0) 955 return bss; 956 } 957 return NULL; 958 } 959 #endif /* CONFIG_P2P */ 960 961 962 /** 963 * wpa_bss_get_id - Fetch a BSS table entry based on identifier 964 * @wpa_s: Pointer to wpa_supplicant data 965 * @id: Unique identifier (struct wpa_bss::id) assigned for the entry 966 * Returns: Pointer to the BSS entry or %NULL if not found 967 */ 968 struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id) 969 { 970 struct wpa_bss *bss; 971 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 972 if (bss->id == id) 973 return bss; 974 } 975 return NULL; 976 } 977 978 979 /** 980 * wpa_bss_get_id_range - Fetch a BSS table entry based on identifier range 981 * @wpa_s: Pointer to wpa_supplicant data 982 * @idf: Smallest allowed identifier assigned for the entry 983 * @idf: Largest allowed identifier assigned for the entry 984 * Returns: Pointer to the BSS entry or %NULL if not found 985 * 986 * This function is similar to wpa_bss_get_id() but allows a BSS entry with the 987 * smallest id value to be fetched within the specified range without the 988 * caller having to know the exact id. 989 */ 990 struct wpa_bss * wpa_bss_get_id_range(struct wpa_supplicant *wpa_s, 991 unsigned int idf, unsigned int idl) 992 { 993 struct wpa_bss *bss; 994 dl_list_for_each(bss, &wpa_s->bss_id, struct wpa_bss, list_id) { 995 if (bss->id >= idf && bss->id <= idl) 996 return bss; 997 } 998 return NULL; 999 } 1000 1001 1002 /** 1003 * wpa_bss_get_ie - Fetch a specified information element from a BSS entry 1004 * @bss: BSS table entry 1005 * @ie: Information element identitifier (WLAN_EID_*) 1006 * Returns: Pointer to the information element (id field) or %NULL if not found 1007 * 1008 * This function returns the first matching information element in the BSS 1009 * entry. 1010 */ 1011 const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie) 1012 { 1013 const u8 *end, *pos; 1014 1015 pos = (const u8 *) (bss + 1); 1016 end = pos + bss->ie_len; 1017 1018 while (pos + 1 < end) { 1019 if (pos + 2 + pos[1] > end) 1020 break; 1021 if (pos[0] == ie) 1022 return pos; 1023 pos += 2 + pos[1]; 1024 } 1025 1026 return NULL; 1027 } 1028 1029 1030 /** 1031 * wpa_bss_get_vendor_ie - Fetch a vendor information element from a BSS entry 1032 * @bss: BSS table entry 1033 * @vendor_type: Vendor type (four octets starting the IE payload) 1034 * Returns: Pointer to the information element (id field) or %NULL if not found 1035 * 1036 * This function returns the first matching information element in the BSS 1037 * entry. 1038 */ 1039 const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type) 1040 { 1041 const u8 *end, *pos; 1042 1043 pos = (const u8 *) (bss + 1); 1044 end = pos + bss->ie_len; 1045 1046 while (pos + 1 < end) { 1047 if (pos + 2 + pos[1] > end) 1048 break; 1049 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 1050 vendor_type == WPA_GET_BE32(&pos[2])) 1051 return pos; 1052 pos += 2 + pos[1]; 1053 } 1054 1055 return NULL; 1056 } 1057 1058 1059 /** 1060 * wpa_bss_get_vendor_ie_beacon - Fetch a vendor information from a BSS entry 1061 * @bss: BSS table entry 1062 * @vendor_type: Vendor type (four octets starting the IE payload) 1063 * Returns: Pointer to the information element (id field) or %NULL if not found 1064 * 1065 * This function returns the first matching information element in the BSS 1066 * entry. 1067 * 1068 * This function is like wpa_bss_get_vendor_ie(), but uses IE buffer only 1069 * from Beacon frames instead of either Beacon or Probe Response frames. 1070 */ 1071 const u8 * wpa_bss_get_vendor_ie_beacon(const struct wpa_bss *bss, 1072 u32 vendor_type) 1073 { 1074 const u8 *end, *pos; 1075 1076 if (bss->beacon_ie_len == 0) 1077 return NULL; 1078 1079 pos = (const u8 *) (bss + 1); 1080 pos += bss->ie_len; 1081 end = pos + bss->beacon_ie_len; 1082 1083 while (pos + 1 < end) { 1084 if (pos + 2 + pos[1] > end) 1085 break; 1086 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 1087 vendor_type == WPA_GET_BE32(&pos[2])) 1088 return pos; 1089 pos += 2 + pos[1]; 1090 } 1091 1092 return NULL; 1093 } 1094 1095 1096 /** 1097 * wpa_bss_get_vendor_ie_multi - Fetch vendor IE data from a BSS entry 1098 * @bss: BSS table entry 1099 * @vendor_type: Vendor type (four octets starting the IE payload) 1100 * Returns: Pointer to the information element payload or %NULL if not found 1101 * 1102 * This function returns concatenated payload of possibly fragmented vendor 1103 * specific information elements in the BSS entry. The caller is responsible for 1104 * freeing the returned buffer. 1105 */ 1106 struct wpabuf * wpa_bss_get_vendor_ie_multi(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->ie_len); 1113 if (buf == NULL) 1114 return NULL; 1115 1116 pos = (const u8 *) (bss + 1); 1117 end = pos + bss->ie_len; 1118 1119 while (pos + 1 < end) { 1120 if (pos + 2 + pos[1] > end) 1121 break; 1122 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 1123 vendor_type == WPA_GET_BE32(&pos[2])) 1124 wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4); 1125 pos += 2 + pos[1]; 1126 } 1127 1128 if (wpabuf_len(buf) == 0) { 1129 wpabuf_free(buf); 1130 buf = NULL; 1131 } 1132 1133 return buf; 1134 } 1135 1136 1137 /** 1138 * wpa_bss_get_vendor_ie_multi_beacon - Fetch vendor IE data from a BSS entry 1139 * @bss: BSS table entry 1140 * @vendor_type: Vendor type (four octets starting the IE payload) 1141 * Returns: Pointer to the information element payload or %NULL if not found 1142 * 1143 * This function returns concatenated payload of possibly fragmented vendor 1144 * specific information elements in the BSS entry. The caller is responsible for 1145 * freeing the returned buffer. 1146 * 1147 * This function is like wpa_bss_get_vendor_ie_multi(), but uses IE buffer only 1148 * from Beacon frames instead of either Beacon or Probe Response frames. 1149 */ 1150 struct wpabuf * wpa_bss_get_vendor_ie_multi_beacon(const struct wpa_bss *bss, 1151 u32 vendor_type) 1152 { 1153 struct wpabuf *buf; 1154 const u8 *end, *pos; 1155 1156 buf = wpabuf_alloc(bss->beacon_ie_len); 1157 if (buf == NULL) 1158 return NULL; 1159 1160 pos = (const u8 *) (bss + 1); 1161 pos += bss->ie_len; 1162 end = pos + bss->beacon_ie_len; 1163 1164 while (pos + 1 < end) { 1165 if (pos + 2 + pos[1] > end) 1166 break; 1167 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 1168 vendor_type == WPA_GET_BE32(&pos[2])) 1169 wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4); 1170 pos += 2 + pos[1]; 1171 } 1172 1173 if (wpabuf_len(buf) == 0) { 1174 wpabuf_free(buf); 1175 buf = NULL; 1176 } 1177 1178 return buf; 1179 } 1180 1181 1182 /** 1183 * wpa_bss_get_max_rate - Get maximum legacy TX rate supported in a BSS 1184 * @bss: BSS table entry 1185 * Returns: Maximum legacy rate in units of 500 kbps 1186 */ 1187 int wpa_bss_get_max_rate(const struct wpa_bss *bss) 1188 { 1189 int rate = 0; 1190 const u8 *ie; 1191 int i; 1192 1193 ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES); 1194 for (i = 0; ie && i < ie[1]; i++) { 1195 if ((ie[i + 2] & 0x7f) > rate) 1196 rate = ie[i + 2] & 0x7f; 1197 } 1198 1199 ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES); 1200 for (i = 0; ie && i < ie[1]; i++) { 1201 if ((ie[i + 2] & 0x7f) > rate) 1202 rate = ie[i + 2] & 0x7f; 1203 } 1204 1205 return rate; 1206 } 1207 1208 1209 /** 1210 * wpa_bss_get_bit_rates - Get legacy TX rates supported in a BSS 1211 * @bss: BSS table entry 1212 * @rates: Buffer for returning a pointer to the rates list (units of 500 kbps) 1213 * Returns: number of legacy TX rates or -1 on failure 1214 * 1215 * The caller is responsible for freeing the returned buffer with os_free() in 1216 * case of success. 1217 */ 1218 int wpa_bss_get_bit_rates(const struct wpa_bss *bss, u8 **rates) 1219 { 1220 const u8 *ie, *ie2; 1221 int i, j; 1222 unsigned int len; 1223 u8 *r; 1224 1225 ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES); 1226 ie2 = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES); 1227 1228 len = (ie ? ie[1] : 0) + (ie2 ? ie2[1] : 0); 1229 1230 r = os_malloc(len); 1231 if (!r) 1232 return -1; 1233 1234 for (i = 0; ie && i < ie[1]; i++) 1235 r[i] = ie[i + 2] & 0x7f; 1236 1237 for (j = 0; ie2 && j < ie2[1]; j++) 1238 r[i + j] = ie2[j + 2] & 0x7f; 1239 1240 *rates = r; 1241 return len; 1242 } 1243
