1 /* 2 * BSS table 3 * Copyright (c) 2009-2012, 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(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 ANQP_DUP(hs20_osu_providers_list); 102 #endif /* CONFIG_HS20 */ 103 #undef ANQP_DUP 104 105 return n; 106 } 107 108 109 /** 110 * wpa_bss_anqp_unshare_alloc - Unshare ANQP data (if shared) in a BSS entry 111 * @bss: BSS entry 112 * Returns: 0 on success, -1 on failure 113 * 114 * This function ensures the specific BSS entry has an ANQP data structure that 115 * is not shared with any other BSS entry. 116 */ 117 int wpa_bss_anqp_unshare_alloc(struct wpa_bss *bss) 118 { 119 struct wpa_bss_anqp *anqp; 120 121 if (bss->anqp && bss->anqp->users > 1) { 122 /* allocated, but shared - clone an unshared copy */ 123 anqp = wpa_bss_anqp_clone(bss->anqp); 124 if (anqp == NULL) 125 return -1; 126 anqp->users = 1; 127 bss->anqp->users--; 128 bss->anqp = anqp; 129 return 0; 130 } 131 132 if (bss->anqp) 133 return 0; /* already allocated and not shared */ 134 135 /* not allocated - allocate a new storage area */ 136 bss->anqp = wpa_bss_anqp_alloc(); 137 return bss->anqp ? 0 : -1; 138 } 139 140 141 /** 142 * wpa_bss_anqp_free - Free an ANQP data structure 143 * @anqp: ANQP data structure from wpa_bss_anqp_alloc() or wpa_bss_anqp_clone() 144 */ 145 static void wpa_bss_anqp_free(struct wpa_bss_anqp *anqp) 146 { 147 if (anqp == NULL) 148 return; 149 150 anqp->users--; 151 if (anqp->users > 0) { 152 /* Another BSS entry holds a pointer to this ANQP info */ 153 return; 154 } 155 156 #ifdef CONFIG_INTERWORKING 157 wpabuf_free(anqp->venue_name); 158 wpabuf_free(anqp->network_auth_type); 159 wpabuf_free(anqp->roaming_consortium); 160 wpabuf_free(anqp->ip_addr_type_availability); 161 wpabuf_free(anqp->nai_realm); 162 wpabuf_free(anqp->anqp_3gpp); 163 wpabuf_free(anqp->domain_name); 164 #endif /* CONFIG_INTERWORKING */ 165 #ifdef CONFIG_HS20 166 wpabuf_free(anqp->hs20_operator_friendly_name); 167 wpabuf_free(anqp->hs20_wan_metrics); 168 wpabuf_free(anqp->hs20_connection_capability); 169 wpabuf_free(anqp->hs20_operating_class); 170 wpabuf_free(anqp->hs20_osu_providers_list); 171 #endif /* CONFIG_HS20 */ 172 173 os_free(anqp); 174 } 175 176 177 static void wpa_bss_update_pending_connect(struct wpa_supplicant *wpa_s, 178 struct wpa_bss *old_bss, 179 struct wpa_bss *new_bss) 180 { 181 struct wpa_radio_work *work; 182 struct wpa_connect_work *cwork; 183 184 work = radio_work_pending(wpa_s, "sme-connect"); 185 if (!work) 186 work = radio_work_pending(wpa_s, "connect"); 187 if (!work) 188 return; 189 190 cwork = work->ctx; 191 if (cwork->bss != old_bss) 192 return; 193 194 wpa_printf(MSG_DEBUG, 195 "Update BSS pointer for the pending connect radio work"); 196 cwork->bss = new_bss; 197 if (!new_bss) 198 cwork->bss_removed = 1; 199 } 200 201 202 static void wpa_bss_remove(struct wpa_supplicant *wpa_s, struct wpa_bss *bss, 203 const char *reason) 204 { 205 if (wpa_s->last_scan_res) { 206 unsigned int i; 207 for (i = 0; i < wpa_s->last_scan_res_used; i++) { 208 if (wpa_s->last_scan_res[i] == bss) { 209 os_memmove(&wpa_s->last_scan_res[i], 210 &wpa_s->last_scan_res[i + 1], 211 (wpa_s->last_scan_res_used - i - 1) 212 * sizeof(struct wpa_bss *)); 213 wpa_s->last_scan_res_used--; 214 break; 215 } 216 } 217 } 218 wpa_bss_update_pending_connect(wpa_s, bss, NULL); 219 dl_list_del(&bss->list); 220 dl_list_del(&bss->list_id); 221 wpa_s->num_bss--; 222 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR 223 " SSID '%s' due to %s", bss->id, MAC2STR(bss->bssid), 224 wpa_ssid_txt(bss->ssid, bss->ssid_len), reason); 225 wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id); 226 wpa_bss_anqp_free(bss->anqp); 227 os_free(bss); 228 } 229 230 231 /** 232 * wpa_bss_get - Fetch a BSS table entry based on BSSID and SSID 233 * @wpa_s: Pointer to wpa_supplicant data 234 * @bssid: BSSID 235 * @ssid: SSID 236 * @ssid_len: Length of @ssid 237 * Returns: Pointer to the BSS entry or %NULL if not found 238 */ 239 struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid, 240 const u8 *ssid, size_t ssid_len) 241 { 242 struct wpa_bss *bss; 243 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid)) 244 return NULL; 245 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 246 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 && 247 bss->ssid_len == ssid_len && 248 os_memcmp(bss->ssid, ssid, ssid_len) == 0) 249 return bss; 250 } 251 return NULL; 252 } 253 254 255 static void calculate_update_time(const struct os_reltime *fetch_time, 256 unsigned int age_ms, 257 struct os_reltime *update_time) 258 { 259 os_time_t usec; 260 261 update_time->sec = fetch_time->sec; 262 update_time->usec = fetch_time->usec; 263 update_time->sec -= age_ms / 1000; 264 usec = (age_ms % 1000) * 1000; 265 if (update_time->usec < usec) { 266 update_time->sec--; 267 update_time->usec += 1000000; 268 } 269 update_time->usec -= usec; 270 } 271 272 273 static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src, 274 struct os_reltime *fetch_time) 275 { 276 dst->flags = src->flags; 277 os_memcpy(dst->bssid, src->bssid, ETH_ALEN); 278 dst->freq = src->freq; 279 dst->beacon_int = src->beacon_int; 280 dst->caps = src->caps; 281 dst->qual = src->qual; 282 dst->noise = src->noise; 283 dst->level = src->level; 284 dst->tsf = src->tsf; 285 286 calculate_update_time(fetch_time, src->age, &dst->last_update); 287 } 288 289 290 static int wpa_bss_known(struct wpa_supplicant *wpa_s, struct wpa_bss *bss) 291 { 292 struct wpa_ssid *ssid; 293 294 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) { 295 if (ssid->ssid == NULL || ssid->ssid_len == 0) 296 continue; 297 if (ssid->ssid_len == bss->ssid_len && 298 os_memcmp(ssid->ssid, bss->ssid, ssid->ssid_len) == 0) 299 return 1; 300 } 301 302 return 0; 303 } 304 305 306 static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss) 307 { 308 return bss == wpa_s->current_bss || 309 os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 || 310 os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0; 311 } 312 313 314 static int wpa_bss_remove_oldest_unknown(struct wpa_supplicant *wpa_s) 315 { 316 struct wpa_bss *bss; 317 318 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 319 if (!wpa_bss_known(wpa_s, bss)) { 320 wpa_bss_remove(wpa_s, bss, __func__); 321 return 0; 322 } 323 } 324 325 return -1; 326 } 327 328 329 static int wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s) 330 { 331 struct wpa_bss *bss; 332 333 /* 334 * Remove the oldest entry that does not match with any configured 335 * network. 336 */ 337 if (wpa_bss_remove_oldest_unknown(wpa_s) == 0) 338 return 0; 339 340 /* 341 * Remove the oldest entry that isn't currently in use. 342 */ 343 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 344 if (!wpa_bss_in_use(wpa_s, bss)) { 345 wpa_bss_remove(wpa_s, bss, __func__); 346 return 0; 347 } 348 } 349 350 return -1; 351 } 352 353 354 static struct wpa_bss * wpa_bss_add(struct wpa_supplicant *wpa_s, 355 const u8 *ssid, size_t ssid_len, 356 struct wpa_scan_res *res, 357 struct os_reltime *fetch_time) 358 { 359 struct wpa_bss *bss; 360 361 bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len); 362 if (bss == NULL) 363 return NULL; 364 bss->id = wpa_s->bss_next_id++; 365 bss->last_update_idx = wpa_s->bss_update_idx; 366 wpa_bss_copy_res(bss, res, fetch_time); 367 os_memcpy(bss->ssid, ssid, ssid_len); 368 bss->ssid_len = ssid_len; 369 bss->ie_len = res->ie_len; 370 bss->beacon_ie_len = res->beacon_ie_len; 371 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len); 372 wpa_bss_set_hessid(bss); 373 374 if (wpa_s->num_bss + 1 > wpa_s->conf->bss_max_count && 375 wpa_bss_remove_oldest(wpa_s) != 0) { 376 wpa_printf(MSG_ERROR, "Increasing the MAX BSS count to %d " 377 "because all BSSes are in use. We should normally " 378 "not get here!", (int) wpa_s->num_bss + 1); 379 wpa_s->conf->bss_max_count = wpa_s->num_bss + 1; 380 } 381 382 dl_list_add_tail(&wpa_s->bss, &bss->list); 383 dl_list_add_tail(&wpa_s->bss_id, &bss->list_id); 384 wpa_s->num_bss++; 385 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR 386 " SSID '%s'", 387 bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len)); 388 wpas_notify_bss_added(wpa_s, bss->bssid, bss->id); 389 return bss; 390 } 391 392 393 static int are_ies_equal(const struct wpa_bss *old, 394 const struct wpa_scan_res *new, u32 ie) 395 { 396 const u8 *old_ie, *new_ie; 397 struct wpabuf *old_ie_buff = NULL; 398 struct wpabuf *new_ie_buff = NULL; 399 int new_ie_len, old_ie_len, ret, is_multi; 400 401 switch (ie) { 402 case WPA_IE_VENDOR_TYPE: 403 old_ie = wpa_bss_get_vendor_ie(old, ie); 404 new_ie = wpa_scan_get_vendor_ie(new, ie); 405 is_multi = 0; 406 break; 407 case WPS_IE_VENDOR_TYPE: 408 old_ie_buff = wpa_bss_get_vendor_ie_multi(old, ie); 409 new_ie_buff = wpa_scan_get_vendor_ie_multi(new, ie); 410 is_multi = 1; 411 break; 412 case WLAN_EID_RSN: 413 case WLAN_EID_SUPP_RATES: 414 case WLAN_EID_EXT_SUPP_RATES: 415 old_ie = wpa_bss_get_ie(old, ie); 416 new_ie = wpa_scan_get_ie(new, ie); 417 is_multi = 0; 418 break; 419 default: 420 wpa_printf(MSG_DEBUG, "bss: %s: cannot compare IEs", __func__); 421 return 0; 422 } 423 424 if (is_multi) { 425 /* in case of multiple IEs stored in buffer */ 426 old_ie = old_ie_buff ? wpabuf_head_u8(old_ie_buff) : NULL; 427 new_ie = new_ie_buff ? wpabuf_head_u8(new_ie_buff) : NULL; 428 old_ie_len = old_ie_buff ? wpabuf_len(old_ie_buff) : 0; 429 new_ie_len = new_ie_buff ? wpabuf_len(new_ie_buff) : 0; 430 } else { 431 /* in case of single IE */ 432 old_ie_len = old_ie ? old_ie[1] + 2 : 0; 433 new_ie_len = new_ie ? new_ie[1] + 2 : 0; 434 } 435 436 if (!old_ie || !new_ie) 437 ret = !old_ie && !new_ie; 438 else 439 ret = (old_ie_len == new_ie_len && 440 os_memcmp(old_ie, new_ie, old_ie_len) == 0); 441 442 wpabuf_free(old_ie_buff); 443 wpabuf_free(new_ie_buff); 444 445 return ret; 446 } 447 448 449 static u32 wpa_bss_compare_res(const struct wpa_bss *old, 450 const struct wpa_scan_res *new) 451 { 452 u32 changes = 0; 453 int caps_diff = old->caps ^ new->caps; 454 455 if (old->freq != new->freq) 456 changes |= WPA_BSS_FREQ_CHANGED_FLAG; 457 458 if (old->level != new->level) 459 changes |= WPA_BSS_SIGNAL_CHANGED_FLAG; 460 461 if (caps_diff & IEEE80211_CAP_PRIVACY) 462 changes |= WPA_BSS_PRIVACY_CHANGED_FLAG; 463 464 if (caps_diff & IEEE80211_CAP_IBSS) 465 changes |= WPA_BSS_MODE_CHANGED_FLAG; 466 467 if (old->ie_len == new->ie_len && 468 os_memcmp(old + 1, new + 1, old->ie_len) == 0) 469 return changes; 470 changes |= WPA_BSS_IES_CHANGED_FLAG; 471 472 if (!are_ies_equal(old, new, WPA_IE_VENDOR_TYPE)) 473 changes |= WPA_BSS_WPAIE_CHANGED_FLAG; 474 475 if (!are_ies_equal(old, new, WLAN_EID_RSN)) 476 changes |= WPA_BSS_RSNIE_CHANGED_FLAG; 477 478 if (!are_ies_equal(old, new, WPS_IE_VENDOR_TYPE)) 479 changes |= WPA_BSS_WPS_CHANGED_FLAG; 480 481 if (!are_ies_equal(old, new, WLAN_EID_SUPP_RATES) || 482 !are_ies_equal(old, new, WLAN_EID_EXT_SUPP_RATES)) 483 changes |= WPA_BSS_RATES_CHANGED_FLAG; 484 485 return changes; 486 } 487 488 489 static void notify_bss_changes(struct wpa_supplicant *wpa_s, u32 changes, 490 const struct wpa_bss *bss) 491 { 492 if (changes & WPA_BSS_FREQ_CHANGED_FLAG) 493 wpas_notify_bss_freq_changed(wpa_s, bss->id); 494 495 if (changes & WPA_BSS_SIGNAL_CHANGED_FLAG) 496 wpas_notify_bss_signal_changed(wpa_s, bss->id); 497 498 if (changes & WPA_BSS_PRIVACY_CHANGED_FLAG) 499 wpas_notify_bss_privacy_changed(wpa_s, bss->id); 500 501 if (changes & WPA_BSS_MODE_CHANGED_FLAG) 502 wpas_notify_bss_mode_changed(wpa_s, bss->id); 503 504 if (changes & WPA_BSS_WPAIE_CHANGED_FLAG) 505 wpas_notify_bss_wpaie_changed(wpa_s, bss->id); 506 507 if (changes & WPA_BSS_RSNIE_CHANGED_FLAG) 508 wpas_notify_bss_rsnie_changed(wpa_s, bss->id); 509 510 if (changes & WPA_BSS_WPS_CHANGED_FLAG) 511 wpas_notify_bss_wps_changed(wpa_s, bss->id); 512 513 if (changes & WPA_BSS_IES_CHANGED_FLAG) 514 wpas_notify_bss_ies_changed(wpa_s, bss->id); 515 516 if (changes & WPA_BSS_RATES_CHANGED_FLAG) 517 wpas_notify_bss_rates_changed(wpa_s, bss->id); 518 519 wpas_notify_bss_seen(wpa_s, bss->id); 520 } 521 522 523 static struct wpa_bss * 524 wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss, 525 struct wpa_scan_res *res, struct os_reltime *fetch_time) 526 { 527 u32 changes; 528 529 changes = wpa_bss_compare_res(bss, res); 530 bss->scan_miss_count = 0; 531 bss->last_update_idx = wpa_s->bss_update_idx; 532 wpa_bss_copy_res(bss, res, fetch_time); 533 /* Move the entry to the end of the list */ 534 dl_list_del(&bss->list); 535 #ifdef CONFIG_P2P 536 if (wpa_bss_get_vendor_ie(bss, P2P_IE_VENDOR_TYPE) && 537 !wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE)) { 538 /* 539 * This can happen when non-P2P station interface runs a scan 540 * without P2P IE in the Probe Request frame. P2P GO would reply 541 * to that with a Probe Response that does not include P2P IE. 542 * Do not update the IEs in this BSS entry to avoid such loss of 543 * information that may be needed for P2P operations to 544 * determine group information. 545 */ 546 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Do not update scan IEs for " 547 MACSTR " since that would remove P2P IE information", 548 MAC2STR(bss->bssid)); 549 } else 550 #endif /* CONFIG_P2P */ 551 if (bss->ie_len + bss->beacon_ie_len >= 552 res->ie_len + res->beacon_ie_len) { 553 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len); 554 bss->ie_len = res->ie_len; 555 bss->beacon_ie_len = res->beacon_ie_len; 556 } else { 557 struct wpa_bss *nbss; 558 struct dl_list *prev = bss->list_id.prev; 559 dl_list_del(&bss->list_id); 560 nbss = os_realloc(bss, sizeof(*bss) + res->ie_len + 561 res->beacon_ie_len); 562 if (nbss) { 563 unsigned int i; 564 for (i = 0; i < wpa_s->last_scan_res_used; i++) { 565 if (wpa_s->last_scan_res[i] == bss) { 566 wpa_s->last_scan_res[i] = nbss; 567 break; 568 } 569 } 570 if (wpa_s->current_bss == bss) 571 wpa_s->current_bss = nbss; 572 wpa_bss_update_pending_connect(wpa_s, bss, nbss); 573 bss = nbss; 574 os_memcpy(bss + 1, res + 1, 575 res->ie_len + res->beacon_ie_len); 576 bss->ie_len = res->ie_len; 577 bss->beacon_ie_len = res->beacon_ie_len; 578 } 579 dl_list_add(prev, &bss->list_id); 580 } 581 if (changes & WPA_BSS_IES_CHANGED_FLAG) 582 wpa_bss_set_hessid(bss); 583 dl_list_add_tail(&wpa_s->bss, &bss->list); 584 585 notify_bss_changes(wpa_s, changes, bss); 586 587 return bss; 588 } 589 590 591 /** 592 * wpa_bss_update_start - Start a BSS table update from scan results 593 * @wpa_s: Pointer to wpa_supplicant data 594 * 595 * This function is called at the start of each BSS table update round for new 596 * scan results. The actual scan result entries are indicated with calls to 597 * wpa_bss_update_scan_res() and the update round is finished with a call to 598 * wpa_bss_update_end(). 599 */ 600 void wpa_bss_update_start(struct wpa_supplicant *wpa_s) 601 { 602 wpa_s->bss_update_idx++; 603 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Start scan result update %u", 604 wpa_s->bss_update_idx); 605 wpa_s->last_scan_res_used = 0; 606 } 607 608 609 /** 610 * wpa_bss_update_scan_res - Update a BSS table entry based on a scan result 611 * @wpa_s: Pointer to wpa_supplicant data 612 * @res: Scan result 613 * @fetch_time: Time when the result was fetched from the driver 614 * 615 * This function updates a BSS table entry (or adds one) based on a scan result. 616 * This is called separately for each scan result between the calls to 617 * wpa_bss_update_start() and wpa_bss_update_end(). 618 */ 619 void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s, 620 struct wpa_scan_res *res, 621 struct os_reltime *fetch_time) 622 { 623 const u8 *ssid, *p2p; 624 struct wpa_bss *bss; 625 626 if (wpa_s->conf->ignore_old_scan_res) { 627 struct os_reltime update; 628 calculate_update_time(fetch_time, res->age, &update); 629 if (os_reltime_before(&update, &wpa_s->scan_trigger_time)) { 630 struct os_reltime age; 631 os_reltime_sub(&wpa_s->scan_trigger_time, &update, 632 &age); 633 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Ignore driver BSS " 634 "table entry that is %u.%06u seconds older " 635 "than our scan trigger", 636 (unsigned int) age.sec, 637 (unsigned int) age.usec); 638 return; 639 } 640 } 641 642 ssid = wpa_scan_get_ie(res, WLAN_EID_SSID); 643 if (ssid == NULL) { 644 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: No SSID IE included for " 645 MACSTR, MAC2STR(res->bssid)); 646 return; 647 } 648 if (ssid[1] > 32) { 649 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Too long SSID IE included for " 650 MACSTR, MAC2STR(res->bssid)); 651 return; 652 } 653 654 p2p = wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE); 655 #ifdef CONFIG_P2P 656 if (p2p == NULL && 657 wpa_s->p2p_group_interface != NOT_P2P_GROUP_INTERFACE) { 658 /* 659 * If it's a P2P specific interface, then don't update 660 * the scan result without a P2P IE. 661 */ 662 wpa_printf(MSG_DEBUG, "BSS: No P2P IE - skipping BSS " MACSTR 663 " update for P2P interface", MAC2STR(res->bssid)); 664 return; 665 } 666 #endif /* CONFIG_P2P */ 667 if (p2p && ssid[1] == P2P_WILDCARD_SSID_LEN && 668 os_memcmp(ssid + 2, P2P_WILDCARD_SSID, P2P_WILDCARD_SSID_LEN) == 0) 669 return; /* Skip P2P listen discovery results here */ 670 671 /* TODO: add option for ignoring BSSes we are not interested in 672 * (to save memory) */ 673 bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]); 674 if (bss == NULL) 675 bss = wpa_bss_add(wpa_s, ssid + 2, ssid[1], res, fetch_time); 676 else { 677 bss = wpa_bss_update(wpa_s, bss, res, fetch_time); 678 if (wpa_s->last_scan_res) { 679 unsigned int i; 680 for (i = 0; i < wpa_s->last_scan_res_used; i++) { 681 if (bss == wpa_s->last_scan_res[i]) { 682 /* Already in the list */ 683 return; 684 } 685 } 686 } 687 } 688 689 if (bss == NULL) 690 return; 691 if (wpa_s->last_scan_res_used >= wpa_s->last_scan_res_size) { 692 struct wpa_bss **n; 693 unsigned int siz; 694 if (wpa_s->last_scan_res_size == 0) 695 siz = 32; 696 else 697 siz = wpa_s->last_scan_res_size * 2; 698 n = os_realloc_array(wpa_s->last_scan_res, siz, 699 sizeof(struct wpa_bss *)); 700 if (n == NULL) 701 return; 702 wpa_s->last_scan_res = n; 703 wpa_s->last_scan_res_size = siz; 704 } 705 706 if (wpa_s->last_scan_res) 707 wpa_s->last_scan_res[wpa_s->last_scan_res_used++] = bss; 708 } 709 710 711 static int wpa_bss_included_in_scan(const struct wpa_bss *bss, 712 const struct scan_info *info) 713 { 714 int found; 715 size_t i; 716 717 if (info == NULL) 718 return 1; 719 720 if (info->num_freqs) { 721 found = 0; 722 for (i = 0; i < info->num_freqs; i++) { 723 if (bss->freq == info->freqs[i]) { 724 found = 1; 725 break; 726 } 727 } 728 if (!found) 729 return 0; 730 } 731 732 if (info->num_ssids) { 733 found = 0; 734 for (i = 0; i < info->num_ssids; i++) { 735 const struct wpa_driver_scan_ssid *s = &info->ssids[i]; 736 if ((s->ssid == NULL || s->ssid_len == 0) || 737 (s->ssid_len == bss->ssid_len && 738 os_memcmp(s->ssid, bss->ssid, bss->ssid_len) == 739 0)) { 740 found = 1; 741 break; 742 } 743 } 744 if (!found) 745 return 0; 746 } 747 748 return 1; 749 } 750 751 752 /** 753 * wpa_bss_update_end - End a BSS table update from scan results 754 * @wpa_s: Pointer to wpa_supplicant data 755 * @info: Information about scan parameters 756 * @new_scan: Whether this update round was based on a new scan 757 * 758 * This function is called at the end of each BSS table update round for new 759 * scan results. The start of the update was indicated with a call to 760 * wpa_bss_update_start(). 761 */ 762 void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info, 763 int new_scan) 764 { 765 struct wpa_bss *bss, *n; 766 767 os_get_reltime(&wpa_s->last_scan); 768 if (!new_scan) 769 return; /* do not expire entries without new scan */ 770 771 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) { 772 if (wpa_bss_in_use(wpa_s, bss)) 773 continue; 774 if (!wpa_bss_included_in_scan(bss, info)) 775 continue; /* expire only BSSes that were scanned */ 776 if (bss->last_update_idx < wpa_s->bss_update_idx) 777 bss->scan_miss_count++; 778 if (bss->scan_miss_count >= 779 wpa_s->conf->bss_expiration_scan_count) { 780 wpa_bss_remove(wpa_s, bss, "no match in scan"); 781 } 782 } 783 784 wpa_printf(MSG_DEBUG, "BSS: last_scan_res_used=%u/%u", 785 wpa_s->last_scan_res_used, wpa_s->last_scan_res_size); 786 } 787 788 789 /** 790 * wpa_bss_flush_by_age - Flush old BSS entries 791 * @wpa_s: Pointer to wpa_supplicant data 792 * @age: Maximum entry age in seconds 793 * 794 * Remove BSS entries that have not been updated during the last @age seconds. 795 */ 796 void wpa_bss_flush_by_age(struct wpa_supplicant *wpa_s, int age) 797 { 798 struct wpa_bss *bss, *n; 799 struct os_reltime t; 800 801 if (dl_list_empty(&wpa_s->bss)) 802 return; 803 804 os_get_reltime(&t); 805 t.sec -= age; 806 807 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) { 808 if (wpa_bss_in_use(wpa_s, bss)) 809 continue; 810 811 if (os_reltime_before(&bss->last_update, &t)) { 812 wpa_bss_remove(wpa_s, bss, __func__); 813 } else 814 break; 815 } 816 } 817 818 819 static void wpa_bss_timeout(void *eloop_ctx, void *timeout_ctx) 820 { 821 struct wpa_supplicant *wpa_s = eloop_ctx; 822 823 wpa_bss_flush_by_age(wpa_s, wpa_s->conf->bss_expiration_age); 824 eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0, 825 wpa_bss_timeout, wpa_s, NULL); 826 } 827 828 829 /** 830 * wpa_bss_init - Initialize BSS table 831 * @wpa_s: Pointer to wpa_supplicant data 832 * Returns: 0 on success, -1 on failure 833 * 834 * This prepares BSS table lists and timer for periodic updates. The BSS table 835 * is deinitialized with wpa_bss_deinit() once not needed anymore. 836 */ 837 int wpa_bss_init(struct wpa_supplicant *wpa_s) 838 { 839 dl_list_init(&wpa_s->bss); 840 dl_list_init(&wpa_s->bss_id); 841 eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0, 842 wpa_bss_timeout, wpa_s, NULL); 843 return 0; 844 } 845 846 847 /** 848 * wpa_bss_flush - Flush all unused BSS entries 849 * @wpa_s: Pointer to wpa_supplicant data 850 */ 851 void wpa_bss_flush(struct wpa_supplicant *wpa_s) 852 { 853 struct wpa_bss *bss, *n; 854 855 wpa_s->clear_driver_scan_cache = 1; 856 857 if (wpa_s->bss.next == NULL) 858 return; /* BSS table not yet initialized */ 859 860 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) { 861 if (wpa_bss_in_use(wpa_s, bss)) 862 continue; 863 wpa_bss_remove(wpa_s, bss, __func__); 864 } 865 } 866 867 868 /** 869 * wpa_bss_deinit - Deinitialize BSS table 870 * @wpa_s: Pointer to wpa_supplicant data 871 */ 872 void wpa_bss_deinit(struct wpa_supplicant *wpa_s) 873 { 874 eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL); 875 wpa_bss_flush(wpa_s); 876 } 877 878 879 /** 880 * wpa_bss_get_bssid - Fetch a BSS table entry based on BSSID 881 * @wpa_s: Pointer to wpa_supplicant data 882 * @bssid: BSSID 883 * Returns: Pointer to the BSS entry or %NULL if not found 884 */ 885 struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s, 886 const u8 *bssid) 887 { 888 struct wpa_bss *bss; 889 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid)) 890 return NULL; 891 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) { 892 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0) 893 return bss; 894 } 895 return NULL; 896 } 897 898 899 /** 900 * wpa_bss_get_bssid_latest - Fetch the latest BSS table entry based on BSSID 901 * @wpa_s: Pointer to wpa_supplicant data 902 * @bssid: BSSID 903 * Returns: Pointer to the BSS entry or %NULL if not found 904 * 905 * This function is like wpa_bss_get_bssid(), but full BSS table is iterated to 906 * find the entry that has the most recent update. This can help in finding the 907 * correct entry in cases where the SSID of the AP may have changed recently 908 * (e.g., in WPS reconfiguration cases). 909 */ 910 struct wpa_bss * wpa_bss_get_bssid_latest(struct wpa_supplicant *wpa_s, 911 const u8 *bssid) 912 { 913 struct wpa_bss *bss, *found = NULL; 914 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid)) 915 return NULL; 916 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) { 917 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) != 0) 918 continue; 919 if (found == NULL || 920 os_reltime_before(&found->last_update, &bss->last_update)) 921 found = bss; 922 } 923 return found; 924 } 925 926 927 #ifdef CONFIG_P2P 928 /** 929 * wpa_bss_get_p2p_dev_addr - Fetch a BSS table entry based on P2P Device Addr 930 * @wpa_s: Pointer to wpa_supplicant data 931 * @dev_addr: P2P Device Address of the GO 932 * Returns: Pointer to the BSS entry or %NULL if not found 933 */ 934 struct wpa_bss * wpa_bss_get_p2p_dev_addr(struct wpa_supplicant *wpa_s, 935 const u8 *dev_addr) 936 { 937 struct wpa_bss *bss; 938 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) { 939 u8 addr[ETH_ALEN]; 940 if (p2p_parse_dev_addr((const u8 *) (bss + 1), bss->ie_len, 941 addr) == 0 && 942 os_memcmp(addr, dev_addr, ETH_ALEN) == 0) 943 return bss; 944 } 945 return NULL; 946 } 947 #endif /* CONFIG_P2P */ 948 949 950 /** 951 * wpa_bss_get_id - Fetch a BSS table entry based on identifier 952 * @wpa_s: Pointer to wpa_supplicant data 953 * @id: Unique identifier (struct wpa_bss::id) assigned for the entry 954 * Returns: Pointer to the BSS entry or %NULL if not found 955 */ 956 struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id) 957 { 958 struct wpa_bss *bss; 959 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 960 if (bss->id == id) 961 return bss; 962 } 963 return NULL; 964 } 965 966 967 /** 968 * wpa_bss_get_id_range - Fetch a BSS table entry based on identifier range 969 * @wpa_s: Pointer to wpa_supplicant data 970 * @idf: Smallest allowed identifier assigned for the entry 971 * @idf: Largest allowed identifier assigned for the entry 972 * Returns: Pointer to the BSS entry or %NULL if not found 973 * 974 * This function is similar to wpa_bss_get_id() but allows a BSS entry with the 975 * smallest id value to be fetched within the specified range without the 976 * caller having to know the exact id. 977 */ 978 struct wpa_bss * wpa_bss_get_id_range(struct wpa_supplicant *wpa_s, 979 unsigned int idf, unsigned int idl) 980 { 981 struct wpa_bss *bss; 982 dl_list_for_each(bss, &wpa_s->bss_id, struct wpa_bss, list_id) { 983 if (bss->id >= idf && bss->id <= idl) 984 return bss; 985 } 986 return NULL; 987 } 988 989 990 /** 991 * wpa_bss_get_ie - Fetch a specified information element from a BSS entry 992 * @bss: BSS table entry 993 * @ie: Information element identitifier (WLAN_EID_*) 994 * Returns: Pointer to the information element (id field) or %NULL if not found 995 * 996 * This function returns the first matching information element in the BSS 997 * entry. 998 */ 999 const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie) 1000 { 1001 const u8 *end, *pos; 1002 1003 pos = (const u8 *) (bss + 1); 1004 end = pos + bss->ie_len; 1005 1006 while (pos + 1 < end) { 1007 if (pos + 2 + pos[1] > end) 1008 break; 1009 if (pos[0] == ie) 1010 return pos; 1011 pos += 2 + pos[1]; 1012 } 1013 1014 return NULL; 1015 } 1016 1017 1018 /** 1019 * wpa_bss_get_vendor_ie - Fetch a vendor information element from a BSS entry 1020 * @bss: BSS table entry 1021 * @vendor_type: Vendor type (four octets starting the IE payload) 1022 * Returns: Pointer to the information element (id field) or %NULL if not found 1023 * 1024 * This function returns the first matching information element in the BSS 1025 * entry. 1026 */ 1027 const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type) 1028 { 1029 const u8 *end, *pos; 1030 1031 pos = (const u8 *) (bss + 1); 1032 end = pos + bss->ie_len; 1033 1034 while (pos + 1 < end) { 1035 if (pos + 2 + pos[1] > end) 1036 break; 1037 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 1038 vendor_type == WPA_GET_BE32(&pos[2])) 1039 return pos; 1040 pos += 2 + pos[1]; 1041 } 1042 1043 return NULL; 1044 } 1045 1046 1047 /** 1048 * wpa_bss_get_vendor_ie_beacon - Fetch a vendor information from a BSS entry 1049 * @bss: BSS table entry 1050 * @vendor_type: Vendor type (four octets starting the IE payload) 1051 * Returns: Pointer to the information element (id field) or %NULL if not found 1052 * 1053 * This function returns the first matching information element in the BSS 1054 * entry. 1055 * 1056 * This function is like wpa_bss_get_vendor_ie(), but uses IE buffer only 1057 * from Beacon frames instead of either Beacon or Probe Response frames. 1058 */ 1059 const u8 * wpa_bss_get_vendor_ie_beacon(const struct wpa_bss *bss, 1060 u32 vendor_type) 1061 { 1062 const u8 *end, *pos; 1063 1064 if (bss->beacon_ie_len == 0) 1065 return NULL; 1066 1067 pos = (const u8 *) (bss + 1); 1068 pos += bss->ie_len; 1069 end = pos + bss->beacon_ie_len; 1070 1071 while (pos + 1 < end) { 1072 if (pos + 2 + pos[1] > end) 1073 break; 1074 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 1075 vendor_type == WPA_GET_BE32(&pos[2])) 1076 return pos; 1077 pos += 2 + pos[1]; 1078 } 1079 1080 return NULL; 1081 } 1082 1083 1084 /** 1085 * wpa_bss_get_vendor_ie_multi - Fetch vendor IE data from a BSS entry 1086 * @bss: BSS table entry 1087 * @vendor_type: Vendor type (four octets starting the IE payload) 1088 * Returns: Pointer to the information element payload or %NULL if not found 1089 * 1090 * This function returns concatenated payload of possibly fragmented vendor 1091 * specific information elements in the BSS entry. The caller is responsible for 1092 * freeing the returned buffer. 1093 */ 1094 struct wpabuf * wpa_bss_get_vendor_ie_multi(const struct wpa_bss *bss, 1095 u32 vendor_type) 1096 { 1097 struct wpabuf *buf; 1098 const u8 *end, *pos; 1099 1100 buf = wpabuf_alloc(bss->ie_len); 1101 if (buf == NULL) 1102 return NULL; 1103 1104 pos = (const u8 *) (bss + 1); 1105 end = pos + bss->ie_len; 1106 1107 while (pos + 1 < end) { 1108 if (pos + 2 + pos[1] > end) 1109 break; 1110 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 1111 vendor_type == WPA_GET_BE32(&pos[2])) 1112 wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4); 1113 pos += 2 + pos[1]; 1114 } 1115 1116 if (wpabuf_len(buf) == 0) { 1117 wpabuf_free(buf); 1118 buf = NULL; 1119 } 1120 1121 return buf; 1122 } 1123 1124 1125 /** 1126 * wpa_bss_get_vendor_ie_multi_beacon - Fetch vendor IE data from a BSS entry 1127 * @bss: BSS table entry 1128 * @vendor_type: Vendor type (four octets starting the IE payload) 1129 * Returns: Pointer to the information element payload or %NULL if not found 1130 * 1131 * This function returns concatenated payload of possibly fragmented vendor 1132 * specific information elements in the BSS entry. The caller is responsible for 1133 * freeing the returned buffer. 1134 * 1135 * This function is like wpa_bss_get_vendor_ie_multi(), but uses IE buffer only 1136 * from Beacon frames instead of either Beacon or Probe Response frames. 1137 */ 1138 struct wpabuf * wpa_bss_get_vendor_ie_multi_beacon(const struct wpa_bss *bss, 1139 u32 vendor_type) 1140 { 1141 struct wpabuf *buf; 1142 const u8 *end, *pos; 1143 1144 buf = wpabuf_alloc(bss->beacon_ie_len); 1145 if (buf == NULL) 1146 return NULL; 1147 1148 pos = (const u8 *) (bss + 1); 1149 pos += bss->ie_len; 1150 end = pos + bss->beacon_ie_len; 1151 1152 while (pos + 1 < end) { 1153 if (pos + 2 + pos[1] > end) 1154 break; 1155 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 1156 vendor_type == WPA_GET_BE32(&pos[2])) 1157 wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4); 1158 pos += 2 + pos[1]; 1159 } 1160 1161 if (wpabuf_len(buf) == 0) { 1162 wpabuf_free(buf); 1163 buf = NULL; 1164 } 1165 1166 return buf; 1167 } 1168 1169 1170 /** 1171 * wpa_bss_get_max_rate - Get maximum legacy TX rate supported in a BSS 1172 * @bss: BSS table entry 1173 * Returns: Maximum legacy rate in units of 500 kbps 1174 */ 1175 int wpa_bss_get_max_rate(const struct wpa_bss *bss) 1176 { 1177 int rate = 0; 1178 const u8 *ie; 1179 int i; 1180 1181 ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES); 1182 for (i = 0; ie && i < ie[1]; i++) { 1183 if ((ie[i + 2] & 0x7f) > rate) 1184 rate = ie[i + 2] & 0x7f; 1185 } 1186 1187 ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES); 1188 for (i = 0; ie && i < ie[1]; i++) { 1189 if ((ie[i + 2] & 0x7f) > rate) 1190 rate = ie[i + 2] & 0x7f; 1191 } 1192 1193 return rate; 1194 } 1195 1196 1197 /** 1198 * wpa_bss_get_bit_rates - Get legacy TX rates supported in a BSS 1199 * @bss: BSS table entry 1200 * @rates: Buffer for returning a pointer to the rates list (units of 500 kbps) 1201 * Returns: number of legacy TX rates or -1 on failure 1202 * 1203 * The caller is responsible for freeing the returned buffer with os_free() in 1204 * case of success. 1205 */ 1206 int wpa_bss_get_bit_rates(const struct wpa_bss *bss, u8 **rates) 1207 { 1208 const u8 *ie, *ie2; 1209 int i, j; 1210 unsigned int len; 1211 u8 *r; 1212 1213 ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES); 1214 ie2 = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES); 1215 1216 len = (ie ? ie[1] : 0) + (ie2 ? ie2[1] : 0); 1217 1218 r = os_malloc(len); 1219 if (!r) 1220 return -1; 1221 1222 for (i = 0; ie && i < ie[1]; i++) 1223 r[i] = ie[i + 2] & 0x7f; 1224 1225 for (j = 0; ie2 && j < ie2[1]; j++) 1226 r[i + j] = ie2[j + 2] & 0x7f; 1227 1228 *rates = r; 1229 return len; 1230 } 1231
