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