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