1/* 2 * BSS table 3 * Copyright (c) 2009-2012, Jouni Malinen <j@w1.fi> 4 * 5 * This software may be distributed under the terms of the BSD license. 6 * See README for more details. 7 */ 8 9#include "utils/includes.h" 10 11#include "utils/common.h" 12#include "utils/eloop.h" 13#include "common/ieee802_11_defs.h" 14#include "drivers/driver.h" 15#include "wpa_supplicant_i.h" 16#include "config.h" 17#include "notify.h" 18#include "scan.h" 19#include "bss.h" 20 21 22/** 23 * WPA_BSS_EXPIRATION_PERIOD - Period of expiration run in seconds 24 */ 25#define WPA_BSS_EXPIRATION_PERIOD 10 26 27#define WPA_BSS_FREQ_CHANGED_FLAG BIT(0) 28#define WPA_BSS_SIGNAL_CHANGED_FLAG BIT(1) 29#define WPA_BSS_PRIVACY_CHANGED_FLAG BIT(2) 30#define WPA_BSS_MODE_CHANGED_FLAG BIT(3) 31#define WPA_BSS_WPAIE_CHANGED_FLAG BIT(4) 32#define WPA_BSS_RSNIE_CHANGED_FLAG BIT(5) 33#define WPA_BSS_WPS_CHANGED_FLAG BIT(6) 34#define WPA_BSS_RATES_CHANGED_FLAG BIT(7) 35#define WPA_BSS_IES_CHANGED_FLAG BIT(8) 36 37 38static 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 */ 62struct 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 */ 78static 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 */ 116int 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 */ 144static 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 175static 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 */ 211struct 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 227static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src) 228{ 229 os_time_t usec; 230 231 dst->flags = src->flags; 232 os_memcpy(dst->bssid, src->bssid, ETH_ALEN); 233 dst->freq = src->freq; 234 dst->beacon_int = src->beacon_int; 235 dst->caps = src->caps; 236 dst->qual = src->qual; 237 dst->noise = src->noise; 238 dst->level = src->level; 239 dst->tsf = src->tsf; 240 241 os_get_time(&dst->last_update); 242 dst->last_update.sec -= src->age / 1000; 243 usec = (src->age % 1000) * 1000; 244 if (dst->last_update.usec < usec) { 245 dst->last_update.sec--; 246 dst->last_update.usec += 1000000; 247 } 248 dst->last_update.usec -= usec; 249} 250 251 252static int wpa_bss_known(struct wpa_supplicant *wpa_s, struct wpa_bss *bss) 253{ 254 struct wpa_ssid *ssid; 255 256 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) { 257 if (ssid->ssid == NULL || ssid->ssid_len == 0) 258 continue; 259 if (ssid->ssid_len == bss->ssid_len && 260 os_memcmp(ssid->ssid, bss->ssid, ssid->ssid_len) == 0) 261 return 1; 262 } 263 264 return 0; 265} 266 267 268static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss) 269{ 270 return bss == wpa_s->current_bss || 271 os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 || 272 os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0; 273} 274 275 276static int wpa_bss_remove_oldest_unknown(struct wpa_supplicant *wpa_s) 277{ 278 struct wpa_bss *bss; 279 280 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 281 if (!wpa_bss_known(wpa_s, bss)) { 282 wpa_bss_remove(wpa_s, bss, __func__); 283 return 0; 284 } 285 } 286 287 return -1; 288} 289 290 291static int wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s) 292{ 293 struct wpa_bss *bss; 294 295 /* 296 * Remove the oldest entry that does not match with any configured 297 * network. 298 */ 299 if (wpa_bss_remove_oldest_unknown(wpa_s) == 0) 300 return 0; 301 302 /* 303 * Remove the oldest entry that isn't currently in use. 304 */ 305 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 306 if (!wpa_bss_in_use(wpa_s, bss)) { 307 wpa_bss_remove(wpa_s, bss, __func__); 308 return 0; 309 } 310 } 311 312 return -1; 313} 314 315 316static struct wpa_bss * wpa_bss_add(struct wpa_supplicant *wpa_s, 317 const u8 *ssid, size_t ssid_len, 318 struct wpa_scan_res *res) 319{ 320 struct wpa_bss *bss; 321 322 bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len); 323 if (bss == NULL) 324 return NULL; 325 bss->id = wpa_s->bss_next_id++; 326 bss->last_update_idx = wpa_s->bss_update_idx; 327 wpa_bss_copy_res(bss, res); 328 os_memcpy(bss->ssid, ssid, ssid_len); 329 bss->ssid_len = ssid_len; 330 bss->ie_len = res->ie_len; 331 bss->beacon_ie_len = res->beacon_ie_len; 332 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len); 333 wpa_bss_set_hessid(bss); 334 335 dl_list_add_tail(&wpa_s->bss, &bss->list); 336 dl_list_add_tail(&wpa_s->bss_id, &bss->list_id); 337 wpa_s->num_bss++; 338 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR 339 " SSID '%s'", 340 bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len)); 341 wpas_notify_bss_added(wpa_s, bss->bssid, bss->id); 342 if (wpa_s->num_bss > wpa_s->conf->bss_max_count && 343 wpa_bss_remove_oldest(wpa_s) != 0) { 344 wpa_printf(MSG_ERROR, "Increasing the MAX BSS count to %d " 345 "because all BSSes are in use. We should normally " 346 "not get here!", (int) wpa_s->num_bss); 347 wpa_s->conf->bss_max_count = wpa_s->num_bss; 348 } 349 return bss; 350} 351 352 353static int are_ies_equal(const struct wpa_bss *old, 354 const struct wpa_scan_res *new, u32 ie) 355{ 356 const u8 *old_ie, *new_ie; 357 struct wpabuf *old_ie_buff = NULL; 358 struct wpabuf *new_ie_buff = NULL; 359 int new_ie_len, old_ie_len, ret, is_multi; 360 361 switch (ie) { 362 case WPA_IE_VENDOR_TYPE: 363 old_ie = wpa_bss_get_vendor_ie(old, ie); 364 new_ie = wpa_scan_get_vendor_ie(new, ie); 365 is_multi = 0; 366 break; 367 case WPS_IE_VENDOR_TYPE: 368 old_ie_buff = wpa_bss_get_vendor_ie_multi(old, ie); 369 new_ie_buff = wpa_scan_get_vendor_ie_multi(new, ie); 370 is_multi = 1; 371 break; 372 case WLAN_EID_RSN: 373 case WLAN_EID_SUPP_RATES: 374 case WLAN_EID_EXT_SUPP_RATES: 375 old_ie = wpa_bss_get_ie(old, ie); 376 new_ie = wpa_scan_get_ie(new, ie); 377 is_multi = 0; 378 break; 379 default: 380 wpa_printf(MSG_DEBUG, "bss: %s: cannot compare IEs", __func__); 381 return 0; 382 } 383 384 if (is_multi) { 385 /* in case of multiple IEs stored in buffer */ 386 old_ie = old_ie_buff ? wpabuf_head_u8(old_ie_buff) : NULL; 387 new_ie = new_ie_buff ? wpabuf_head_u8(new_ie_buff) : NULL; 388 old_ie_len = old_ie_buff ? wpabuf_len(old_ie_buff) : 0; 389 new_ie_len = new_ie_buff ? wpabuf_len(new_ie_buff) : 0; 390 } else { 391 /* in case of single IE */ 392 old_ie_len = old_ie ? old_ie[1] + 2 : 0; 393 new_ie_len = new_ie ? new_ie[1] + 2 : 0; 394 } 395 396 if (!old_ie || !new_ie) 397 ret = !old_ie && !new_ie; 398 else 399 ret = (old_ie_len == new_ie_len && 400 os_memcmp(old_ie, new_ie, old_ie_len) == 0); 401 402 wpabuf_free(old_ie_buff); 403 wpabuf_free(new_ie_buff); 404 405 return ret; 406} 407 408 409static u32 wpa_bss_compare_res(const struct wpa_bss *old, 410 const struct wpa_scan_res *new) 411{ 412 u32 changes = 0; 413 int caps_diff = old->caps ^ new->caps; 414 415 if (old->freq != new->freq) 416 changes |= WPA_BSS_FREQ_CHANGED_FLAG; 417 418 if (old->level != new->level) 419 changes |= WPA_BSS_SIGNAL_CHANGED_FLAG; 420 421 if (caps_diff & IEEE80211_CAP_PRIVACY) 422 changes |= WPA_BSS_PRIVACY_CHANGED_FLAG; 423 424 if (caps_diff & IEEE80211_CAP_IBSS) 425 changes |= WPA_BSS_MODE_CHANGED_FLAG; 426 427 if (old->ie_len == new->ie_len && 428 os_memcmp(old + 1, new + 1, old->ie_len) == 0) 429 return changes; 430 changes |= WPA_BSS_IES_CHANGED_FLAG; 431 432 if (!are_ies_equal(old, new, WPA_IE_VENDOR_TYPE)) 433 changes |= WPA_BSS_WPAIE_CHANGED_FLAG; 434 435 if (!are_ies_equal(old, new, WLAN_EID_RSN)) 436 changes |= WPA_BSS_RSNIE_CHANGED_FLAG; 437 438 if (!are_ies_equal(old, new, WPS_IE_VENDOR_TYPE)) 439 changes |= WPA_BSS_WPS_CHANGED_FLAG; 440 441 if (!are_ies_equal(old, new, WLAN_EID_SUPP_RATES) || 442 !are_ies_equal(old, new, WLAN_EID_EXT_SUPP_RATES)) 443 changes |= WPA_BSS_RATES_CHANGED_FLAG; 444 445 return changes; 446} 447 448 449static void notify_bss_changes(struct wpa_supplicant *wpa_s, u32 changes, 450 const struct wpa_bss *bss) 451{ 452 if (changes & WPA_BSS_FREQ_CHANGED_FLAG) 453 wpas_notify_bss_freq_changed(wpa_s, bss->id); 454 455 if (changes & WPA_BSS_SIGNAL_CHANGED_FLAG) 456 wpas_notify_bss_signal_changed(wpa_s, bss->id); 457 458 if (changes & WPA_BSS_PRIVACY_CHANGED_FLAG) 459 wpas_notify_bss_privacy_changed(wpa_s, bss->id); 460 461 if (changes & WPA_BSS_MODE_CHANGED_FLAG) 462 wpas_notify_bss_mode_changed(wpa_s, bss->id); 463 464 if (changes & WPA_BSS_WPAIE_CHANGED_FLAG) 465 wpas_notify_bss_wpaie_changed(wpa_s, bss->id); 466 467 if (changes & WPA_BSS_RSNIE_CHANGED_FLAG) 468 wpas_notify_bss_rsnie_changed(wpa_s, bss->id); 469 470 if (changes & WPA_BSS_WPS_CHANGED_FLAG) 471 wpas_notify_bss_wps_changed(wpa_s, bss->id); 472 473 if (changes & WPA_BSS_IES_CHANGED_FLAG) 474 wpas_notify_bss_ies_changed(wpa_s, bss->id); 475 476 if (changes & WPA_BSS_RATES_CHANGED_FLAG) 477 wpas_notify_bss_rates_changed(wpa_s, bss->id); 478} 479 480 481static struct wpa_bss * 482wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss, 483 struct wpa_scan_res *res) 484{ 485 u32 changes; 486 487 changes = wpa_bss_compare_res(bss, res); 488 bss->scan_miss_count = 0; 489 bss->last_update_idx = wpa_s->bss_update_idx; 490 wpa_bss_copy_res(bss, res); 491 /* Move the entry to the end of the list */ 492 dl_list_del(&bss->list); 493 if (bss->ie_len + bss->beacon_ie_len >= 494 res->ie_len + res->beacon_ie_len) { 495 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len); 496 bss->ie_len = res->ie_len; 497 bss->beacon_ie_len = res->beacon_ie_len; 498 } else { 499 struct wpa_bss *nbss; 500 struct dl_list *prev = bss->list_id.prev; 501 dl_list_del(&bss->list_id); 502 nbss = os_realloc(bss, sizeof(*bss) + res->ie_len + 503 res->beacon_ie_len); 504 if (nbss) { 505 unsigned int i; 506 for (i = 0; i < wpa_s->last_scan_res_used; i++) { 507 if (wpa_s->last_scan_res[i] == bss) { 508 wpa_s->last_scan_res[i] = nbss; 509 break; 510 } 511 } 512 if (wpa_s->current_bss == bss) 513 wpa_s->current_bss = nbss; 514 bss = nbss; 515 os_memcpy(bss + 1, res + 1, 516 res->ie_len + res->beacon_ie_len); 517 bss->ie_len = res->ie_len; 518 bss->beacon_ie_len = res->beacon_ie_len; 519 } 520 dl_list_add(prev, &bss->list_id); 521 } 522 if (changes & WPA_BSS_IES_CHANGED_FLAG) 523 wpa_bss_set_hessid(bss); 524 dl_list_add_tail(&wpa_s->bss, &bss->list); 525 526 notify_bss_changes(wpa_s, changes, bss); 527 528 return bss; 529} 530 531 532/** 533 * wpa_bss_update_start - Start a BSS table update from scan results 534 * @wpa_s: Pointer to wpa_supplicant data 535 * 536 * This function is called at the start of each BSS table update round for new 537 * scan results. The actual scan result entries are indicated with calls to 538 * wpa_bss_update_scan_res() and the update round is finished with a call to 539 * wpa_bss_update_end(). 540 */ 541void wpa_bss_update_start(struct wpa_supplicant *wpa_s) 542{ 543 wpa_s->bss_update_idx++; 544 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Start scan result update %u", 545 wpa_s->bss_update_idx); 546 wpa_s->last_scan_res_used = 0; 547} 548 549 550/** 551 * wpa_bss_update_scan_res - Update a BSS table entry based on a scan result 552 * @wpa_s: Pointer to wpa_supplicant data 553 * @res: Scan result 554 * 555 * This function updates a BSS table entry (or adds one) based on a scan result. 556 * This is called separately for each scan result between the calls to 557 * wpa_bss_update_start() and wpa_bss_update_end(). 558 */ 559void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s, 560 struct wpa_scan_res *res) 561{ 562 const u8 *ssid, *p2p; 563 struct wpa_bss *bss; 564 565 ssid = wpa_scan_get_ie(res, WLAN_EID_SSID); 566 if (ssid == NULL) { 567 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: No SSID IE included for " 568 MACSTR, MAC2STR(res->bssid)); 569 return; 570 } 571 if (ssid[1] > 32) { 572 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Too long SSID IE included for " 573 MACSTR, MAC2STR(res->bssid)); 574 return; 575 } 576 577 p2p = wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE); 578#ifdef CONFIG_P2P 579 if (p2p == NULL && 580 wpa_s->p2p_group_interface != NOT_P2P_GROUP_INTERFACE) { 581 /* 582 * If it's a P2P specific interface, then don't update 583 * the scan result without a P2P IE. 584 */ 585 wpa_printf(MSG_DEBUG, "BSS: No P2P IE - skipping BSS " MACSTR 586 " update for P2P interface", MAC2STR(res->bssid)); 587 return; 588 } 589#endif /* CONFIG_P2P */ 590 if (p2p && ssid[1] == P2P_WILDCARD_SSID_LEN && 591 os_memcmp(ssid + 2, P2P_WILDCARD_SSID, P2P_WILDCARD_SSID_LEN) == 0) 592 return; /* Skip P2P listen discovery results here */ 593 594 /* TODO: add option for ignoring BSSes we are not interested in 595 * (to save memory) */ 596 bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]); 597 if (bss == NULL) 598 bss = wpa_bss_add(wpa_s, ssid + 2, ssid[1], res); 599 else 600 bss = wpa_bss_update(wpa_s, bss, res); 601 602 if (bss == NULL) 603 return; 604 if (wpa_s->last_scan_res_used >= wpa_s->last_scan_res_size) { 605 struct wpa_bss **n; 606 unsigned int siz; 607 if (wpa_s->last_scan_res_size == 0) 608 siz = 32; 609 else 610 siz = wpa_s->last_scan_res_size * 2; 611 n = os_realloc_array(wpa_s->last_scan_res, siz, 612 sizeof(struct wpa_bss *)); 613 if (n == NULL) 614 return; 615 wpa_s->last_scan_res = n; 616 wpa_s->last_scan_res_size = siz; 617 } 618 619 wpa_s->last_scan_res[wpa_s->last_scan_res_used++] = bss; 620} 621 622 623static int wpa_bss_included_in_scan(const struct wpa_bss *bss, 624 const struct scan_info *info) 625{ 626 int found; 627 size_t i; 628 629 if (info == NULL) 630 return 1; 631 632 if (info->num_freqs) { 633 found = 0; 634 for (i = 0; i < info->num_freqs; i++) { 635 if (bss->freq == info->freqs[i]) { 636 found = 1; 637 break; 638 } 639 } 640 if (!found) 641 return 0; 642 } 643 644 if (info->num_ssids) { 645 found = 0; 646 for (i = 0; i < info->num_ssids; i++) { 647 const struct wpa_driver_scan_ssid *s = &info->ssids[i]; 648 if ((s->ssid == NULL || s->ssid_len == 0) || 649 (s->ssid_len == bss->ssid_len && 650 os_memcmp(s->ssid, bss->ssid, bss->ssid_len) == 651 0)) { 652 found = 1; 653 break; 654 } 655 } 656 if (!found) 657 return 0; 658 } 659 660 return 1; 661} 662 663 664/** 665 * wpa_bss_update_end - End a BSS table update from scan results 666 * @wpa_s: Pointer to wpa_supplicant data 667 * @info: Information about scan parameters 668 * @new_scan: Whether this update round was based on a new scan 669 * 670 * This function is called at the end of each BSS table update round for new 671 * scan results. The start of the update was indicated with a call to 672 * wpa_bss_update_start(). 673 */ 674void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info, 675 int new_scan) 676{ 677 struct wpa_bss *bss, *n; 678 679 wpa_s->last_scan_full = 0; 680 os_get_time(&wpa_s->last_scan); 681 if (!new_scan) 682 return; /* do not expire entries without new scan */ 683 684 if (info && !info->aborted && !info->freqs) { 685 size_t i; 686 if (info->num_ssids == 0) { 687 wpa_s->last_scan_full = 1; 688 } else { 689 for (i = 0; i < info->num_ssids; i++) { 690 if (info->ssids[i].ssid == NULL || 691 info->ssids[i].ssid_len == 0) { 692 wpa_s->last_scan_full = 1; 693 break; 694 } 695 } 696 } 697 } 698 699 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) { 700 if (wpa_bss_in_use(wpa_s, bss)) 701 continue; 702 if (!wpa_bss_included_in_scan(bss, info)) 703 continue; /* expire only BSSes that were scanned */ 704 if (bss->last_update_idx < wpa_s->bss_update_idx) 705 bss->scan_miss_count++; 706 if (bss->scan_miss_count >= 707 wpa_s->conf->bss_expiration_scan_count) { 708 wpa_bss_remove(wpa_s, bss, "no match in scan"); 709 } 710 } 711 712 wpa_printf(MSG_DEBUG, "BSS: last_scan_res_used=%u/%u " 713 "last_scan_full=%d", 714 wpa_s->last_scan_res_used, wpa_s->last_scan_res_size, 715 wpa_s->last_scan_full); 716} 717 718 719/** 720 * wpa_bss_flush_by_age - Flush old BSS entries 721 * @wpa_s: Pointer to wpa_supplicant data 722 * @age: Maximum entry age in seconds 723 * 724 * Remove BSS entries that have not been updated during the last @age seconds. 725 */ 726void wpa_bss_flush_by_age(struct wpa_supplicant *wpa_s, int age) 727{ 728 struct wpa_bss *bss, *n; 729 struct os_time t; 730 731 if (dl_list_empty(&wpa_s->bss)) 732 return; 733 734 os_get_time(&t); 735 t.sec -= age; 736 737 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) { 738 if (wpa_bss_in_use(wpa_s, bss)) 739 continue; 740 741 if (os_time_before(&bss->last_update, &t)) { 742 wpa_bss_remove(wpa_s, bss, __func__); 743 } else 744 break; 745 } 746} 747 748 749static void wpa_bss_timeout(void *eloop_ctx, void *timeout_ctx) 750{ 751 struct wpa_supplicant *wpa_s = eloop_ctx; 752 753 wpa_bss_flush_by_age(wpa_s, wpa_s->conf->bss_expiration_age); 754 eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0, 755 wpa_bss_timeout, wpa_s, NULL); 756} 757 758 759/** 760 * wpa_bss_init - Initialize BSS table 761 * @wpa_s: Pointer to wpa_supplicant data 762 * Returns: 0 on success, -1 on failure 763 * 764 * This prepares BSS table lists and timer for periodic updates. The BSS table 765 * is deinitialized with wpa_bss_deinit() once not needed anymore. 766 */ 767int wpa_bss_init(struct wpa_supplicant *wpa_s) 768{ 769 dl_list_init(&wpa_s->bss); 770 dl_list_init(&wpa_s->bss_id); 771 eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0, 772 wpa_bss_timeout, wpa_s, NULL); 773 return 0; 774} 775 776 777/** 778 * wpa_bss_flush - Flush all unused BSS entries 779 * @wpa_s: Pointer to wpa_supplicant data 780 */ 781void wpa_bss_flush(struct wpa_supplicant *wpa_s) 782{ 783 struct wpa_bss *bss, *n; 784 785 if (wpa_s->bss.next == NULL) 786 return; /* BSS table not yet initialized */ 787 788 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) { 789 if (wpa_bss_in_use(wpa_s, bss)) 790 continue; 791 wpa_bss_remove(wpa_s, bss, __func__); 792 } 793} 794 795 796/** 797 * wpa_bss_deinit - Deinitialize BSS table 798 * @wpa_s: Pointer to wpa_supplicant data 799 */ 800void wpa_bss_deinit(struct wpa_supplicant *wpa_s) 801{ 802 eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL); 803 wpa_bss_flush(wpa_s); 804} 805 806 807/** 808 * wpa_bss_get_bssid - Fetch a BSS table entry based on BSSID 809 * @wpa_s: Pointer to wpa_supplicant data 810 * @bssid: BSSID 811 * Returns: Pointer to the BSS entry or %NULL if not found 812 */ 813struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s, 814 const u8 *bssid) 815{ 816 struct wpa_bss *bss; 817 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid)) 818 return NULL; 819 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) { 820 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0) 821 return bss; 822 } 823 return NULL; 824} 825 826 827#ifdef CONFIG_P2P 828/** 829 * wpa_bss_get_p2p_dev_addr - Fetch a BSS table entry based on P2P Device Addr 830 * @wpa_s: Pointer to wpa_supplicant data 831 * @dev_addr: P2P Device Address of the GO 832 * Returns: Pointer to the BSS entry or %NULL if not found 833 */ 834struct wpa_bss * wpa_bss_get_p2p_dev_addr(struct wpa_supplicant *wpa_s, 835 const u8 *dev_addr) 836{ 837 struct wpa_bss *bss; 838 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) { 839 u8 addr[ETH_ALEN]; 840 if (p2p_parse_dev_addr((const u8 *) (bss + 1), bss->ie_len, 841 addr) == 0 && 842 os_memcmp(addr, dev_addr, ETH_ALEN) == 0) 843 return bss; 844 } 845 return NULL; 846} 847#endif /* CONFIG_P2P */ 848 849 850/** 851 * wpa_bss_get_id - Fetch a BSS table entry based on identifier 852 * @wpa_s: Pointer to wpa_supplicant data 853 * @id: Unique identifier (struct wpa_bss::id) assigned for the entry 854 * Returns: Pointer to the BSS entry or %NULL if not found 855 */ 856struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id) 857{ 858 struct wpa_bss *bss; 859 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) { 860 if (bss->id == id) 861 return bss; 862 } 863 return NULL; 864} 865 866 867/** 868 * wpa_bss_get_ie - Fetch a specified information element from a BSS entry 869 * @bss: BSS table entry 870 * @ie: Information element identitifier (WLAN_EID_*) 871 * Returns: Pointer to the information element (id field) or %NULL if not found 872 * 873 * This function returns the first matching information element in the BSS 874 * entry. 875 */ 876const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie) 877{ 878 const u8 *end, *pos; 879 880 pos = (const u8 *) (bss + 1); 881 end = pos + bss->ie_len; 882 883 while (pos + 1 < end) { 884 if (pos + 2 + pos[1] > end) 885 break; 886 if (pos[0] == ie) 887 return pos; 888 pos += 2 + pos[1]; 889 } 890 891 return NULL; 892} 893 894 895/** 896 * wpa_bss_get_vendor_ie - Fetch a vendor information element from a BSS entry 897 * @bss: BSS table entry 898 * @vendor_type: Vendor type (four octets starting the IE payload) 899 * Returns: Pointer to the information element (id field) or %NULL if not found 900 * 901 * This function returns the first matching information element in the BSS 902 * entry. 903 */ 904const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type) 905{ 906 const u8 *end, *pos; 907 908 pos = (const u8 *) (bss + 1); 909 end = pos + bss->ie_len; 910 911 while (pos + 1 < end) { 912 if (pos + 2 + pos[1] > end) 913 break; 914 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 915 vendor_type == WPA_GET_BE32(&pos[2])) 916 return pos; 917 pos += 2 + pos[1]; 918 } 919 920 return NULL; 921} 922 923 924/** 925 * wpa_bss_get_vendor_ie_multi - Fetch vendor IE data from a BSS entry 926 * @bss: BSS table entry 927 * @vendor_type: Vendor type (four octets starting the IE payload) 928 * Returns: Pointer to the information element payload or %NULL if not found 929 * 930 * This function returns concatenated payload of possibly fragmented vendor 931 * specific information elements in the BSS entry. The caller is responsible for 932 * freeing the returned buffer. 933 */ 934struct wpabuf * wpa_bss_get_vendor_ie_multi(const struct wpa_bss *bss, 935 u32 vendor_type) 936{ 937 struct wpabuf *buf; 938 const u8 *end, *pos; 939 940 buf = wpabuf_alloc(bss->ie_len); 941 if (buf == NULL) 942 return NULL; 943 944 pos = (const u8 *) (bss + 1); 945 end = pos + bss->ie_len; 946 947 while (pos + 1 < end) { 948 if (pos + 2 + pos[1] > end) 949 break; 950 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 951 vendor_type == WPA_GET_BE32(&pos[2])) 952 wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4); 953 pos += 2 + pos[1]; 954 } 955 956 if (wpabuf_len(buf) == 0) { 957 wpabuf_free(buf); 958 buf = NULL; 959 } 960 961 return buf; 962} 963 964 965/** 966 * wpa_bss_get_vendor_ie_multi_beacon - Fetch vendor IE data from a BSS entry 967 * @bss: BSS table entry 968 * @vendor_type: Vendor type (four octets starting the IE payload) 969 * Returns: Pointer to the information element payload or %NULL if not found 970 * 971 * This function returns concatenated payload of possibly fragmented vendor 972 * specific information elements in the BSS entry. The caller is responsible for 973 * freeing the returned buffer. 974 * 975 * This function is like wpa_bss_get_vendor_ie_multi(), but uses IE buffer only 976 * from Beacon frames instead of either Beacon or Probe Response frames. 977 */ 978struct wpabuf * wpa_bss_get_vendor_ie_multi_beacon(const struct wpa_bss *bss, 979 u32 vendor_type) 980{ 981 struct wpabuf *buf; 982 const u8 *end, *pos; 983 984 buf = wpabuf_alloc(bss->beacon_ie_len); 985 if (buf == NULL) 986 return NULL; 987 988 pos = (const u8 *) (bss + 1); 989 pos += bss->ie_len; 990 end = pos + bss->beacon_ie_len; 991 992 while (pos + 1 < end) { 993 if (pos + 2 + pos[1] > end) 994 break; 995 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && 996 vendor_type == WPA_GET_BE32(&pos[2])) 997 wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4); 998 pos += 2 + pos[1]; 999 } 1000 1001 if (wpabuf_len(buf) == 0) { 1002 wpabuf_free(buf); 1003 buf = NULL; 1004 } 1005 1006 return buf; 1007} 1008 1009 1010/** 1011 * wpa_bss_get_max_rate - Get maximum legacy TX rate supported in a BSS 1012 * @bss: BSS table entry 1013 * Returns: Maximum legacy rate in units of 500 kbps 1014 */ 1015int wpa_bss_get_max_rate(const struct wpa_bss *bss) 1016{ 1017 int rate = 0; 1018 const u8 *ie; 1019 int i; 1020 1021 ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES); 1022 for (i = 0; ie && i < ie[1]; i++) { 1023 if ((ie[i + 2] & 0x7f) > rate) 1024 rate = ie[i + 2] & 0x7f; 1025 } 1026 1027 ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES); 1028 for (i = 0; ie && i < ie[1]; i++) { 1029 if ((ie[i + 2] & 0x7f) > rate) 1030 rate = ie[i + 2] & 0x7f; 1031 } 1032 1033 return rate; 1034} 1035 1036 1037/** 1038 * wpa_bss_get_bit_rates - Get legacy TX rates supported in a BSS 1039 * @bss: BSS table entry 1040 * @rates: Buffer for returning a pointer to the rates list (units of 500 kbps) 1041 * Returns: number of legacy TX rates or -1 on failure 1042 * 1043 * The caller is responsible for freeing the returned buffer with os_free() in 1044 * case of success. 1045 */ 1046int wpa_bss_get_bit_rates(const struct wpa_bss *bss, u8 **rates) 1047{ 1048 const u8 *ie, *ie2; 1049 int i, j; 1050 unsigned int len; 1051 u8 *r; 1052 1053 ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES); 1054 ie2 = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES); 1055 1056 len = (ie ? ie[1] : 0) + (ie2 ? ie2[1] : 0); 1057 1058 r = os_malloc(len); 1059 if (!r) 1060 return -1; 1061 1062 for (i = 0; ie && i < ie[1]; i++) 1063 r[i] = ie[i + 2] & 0x7f; 1064 1065 for (j = 0; ie2 && j < ie2[1]; j++) 1066 r[i + j] = ie2[j + 2] & 0x7f; 1067 1068 *rates = r; 1069 return len; 1070} 1071