1 /*
2 * BSS table
3 * Copyright (c) 2009-2015, 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 #define WPA_BSS_FREQ_CHANGED_FLAG BIT(0)
23 #define WPA_BSS_SIGNAL_CHANGED_FLAG BIT(1)
24 #define WPA_BSS_PRIVACY_CHANGED_FLAG BIT(2)
25 #define WPA_BSS_MODE_CHANGED_FLAG BIT(3)
26 #define WPA_BSS_WPAIE_CHANGED_FLAG BIT(4)
27 #define WPA_BSS_RSNIE_CHANGED_FLAG BIT(5)
28 #define WPA_BSS_WPS_CHANGED_FLAG BIT(6)
29 #define WPA_BSS_RATES_CHANGED_FLAG BIT(7)
30 #define WPA_BSS_IES_CHANGED_FLAG BIT(8)
31
32
wpa_bss_set_hessid(struct wpa_bss * bss)33 static void wpa_bss_set_hessid(struct wpa_bss *bss)
34 {
35 #ifdef CONFIG_INTERWORKING
36 const u8 *ie = wpa_bss_get_ie(bss, WLAN_EID_INTERWORKING);
37 if (ie == NULL || (ie[1] != 7 && ie[1] != 9)) {
38 os_memset(bss->hessid, 0, ETH_ALEN);
39 return;
40 }
41 if (ie[1] == 7)
42 os_memcpy(bss->hessid, ie + 3, ETH_ALEN);
43 else
44 os_memcpy(bss->hessid, ie + 5, ETH_ALEN);
45 #endif /* CONFIG_INTERWORKING */
46 }
47
48
49 /**
50 * wpa_bss_anqp_alloc - Allocate ANQP data structure for a BSS entry
51 * Returns: Allocated ANQP data structure or %NULL on failure
52 *
53 * The allocated ANQP data structure has its users count set to 1. It may be
54 * shared by multiple BSS entries and each shared entry is freed with
55 * wpa_bss_anqp_free().
56 */
wpa_bss_anqp_alloc(void)57 struct wpa_bss_anqp * wpa_bss_anqp_alloc(void)
58 {
59 struct wpa_bss_anqp *anqp;
60 anqp = os_zalloc(sizeof(*anqp));
61 if (anqp == NULL)
62 return NULL;
63 anqp->users = 1;
64 return anqp;
65 }
66
67
68 /**
69 * wpa_bss_anqp_clone - Clone an ANQP data structure
70 * @anqp: ANQP data structure from wpa_bss_anqp_alloc()
71 * Returns: Cloned ANQP data structure or %NULL on failure
72 */
wpa_bss_anqp_clone(struct wpa_bss_anqp * anqp)73 static struct wpa_bss_anqp * wpa_bss_anqp_clone(struct wpa_bss_anqp *anqp)
74 {
75 struct wpa_bss_anqp *n;
76
77 n = os_zalloc(sizeof(*n));
78 if (n == NULL)
79 return NULL;
80
81 #define ANQP_DUP(f) if (anqp->f) n->f = wpabuf_dup(anqp->f)
82 #ifdef CONFIG_INTERWORKING
83 ANQP_DUP(capability_list);
84 ANQP_DUP(venue_name);
85 ANQP_DUP(network_auth_type);
86 ANQP_DUP(roaming_consortium);
87 ANQP_DUP(ip_addr_type_availability);
88 ANQP_DUP(nai_realm);
89 ANQP_DUP(anqp_3gpp);
90 ANQP_DUP(domain_name);
91 #endif /* CONFIG_INTERWORKING */
92 #ifdef CONFIG_HS20
93 ANQP_DUP(hs20_capability_list);
94 ANQP_DUP(hs20_operator_friendly_name);
95 ANQP_DUP(hs20_wan_metrics);
96 ANQP_DUP(hs20_connection_capability);
97 ANQP_DUP(hs20_operating_class);
98 ANQP_DUP(hs20_osu_providers_list);
99 #endif /* CONFIG_HS20 */
100 #undef ANQP_DUP
101
102 return n;
103 }
104
105
106 /**
107 * wpa_bss_anqp_unshare_alloc - Unshare ANQP data (if shared) in a BSS entry
108 * @bss: BSS entry
109 * Returns: 0 on success, -1 on failure
110 *
111 * This function ensures the specific BSS entry has an ANQP data structure that
112 * is not shared with any other BSS entry.
113 */
wpa_bss_anqp_unshare_alloc(struct wpa_bss * bss)114 int wpa_bss_anqp_unshare_alloc(struct wpa_bss *bss)
115 {
116 struct wpa_bss_anqp *anqp;
117
118 if (bss->anqp && bss->anqp->users > 1) {
119 /* allocated, but shared - clone an unshared copy */
120 anqp = wpa_bss_anqp_clone(bss->anqp);
121 if (anqp == NULL)
122 return -1;
123 anqp->users = 1;
124 bss->anqp->users--;
125 bss->anqp = anqp;
126 return 0;
127 }
128
129 if (bss->anqp)
130 return 0; /* already allocated and not shared */
131
132 /* not allocated - allocate a new storage area */
133 bss->anqp = wpa_bss_anqp_alloc();
134 return bss->anqp ? 0 : -1;
135 }
136
137
138 /**
139 * wpa_bss_anqp_free - Free an ANQP data structure
140 * @anqp: ANQP data structure from wpa_bss_anqp_alloc() or wpa_bss_anqp_clone()
141 */
wpa_bss_anqp_free(struct wpa_bss_anqp * anqp)142 static void wpa_bss_anqp_free(struct wpa_bss_anqp *anqp)
143 {
144 if (anqp == NULL)
145 return;
146
147 anqp->users--;
148 if (anqp->users > 0) {
149 /* Another BSS entry holds a pointer to this ANQP info */
150 return;
151 }
152
153 #ifdef CONFIG_INTERWORKING
154 wpabuf_free(anqp->capability_list);
155 wpabuf_free(anqp->venue_name);
156 wpabuf_free(anqp->network_auth_type);
157 wpabuf_free(anqp->roaming_consortium);
158 wpabuf_free(anqp->ip_addr_type_availability);
159 wpabuf_free(anqp->nai_realm);
160 wpabuf_free(anqp->anqp_3gpp);
161 wpabuf_free(anqp->domain_name);
162 #endif /* CONFIG_INTERWORKING */
163 #ifdef CONFIG_HS20
164 wpabuf_free(anqp->hs20_capability_list);
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 wpabuf_free(anqp->hs20_osu_providers_list);
170 #endif /* CONFIG_HS20 */
171
172 os_free(anqp);
173 }
174
175
wpa_bss_update_pending_connect(struct wpa_supplicant * wpa_s,struct wpa_bss * old_bss,struct wpa_bss * new_bss)176 static void wpa_bss_update_pending_connect(struct wpa_supplicant *wpa_s,
177 struct wpa_bss *old_bss,
178 struct wpa_bss *new_bss)
179 {
180 struct wpa_radio_work *work;
181 struct wpa_connect_work *cwork;
182
183 work = radio_work_pending(wpa_s, "sme-connect");
184 if (!work)
185 work = radio_work_pending(wpa_s, "connect");
186 if (!work)
187 return;
188
189 cwork = work->ctx;
190 if (cwork->bss != old_bss)
191 return;
192
193 wpa_printf(MSG_DEBUG,
194 "Update BSS pointer for the pending connect radio work");
195 cwork->bss = new_bss;
196 if (!new_bss)
197 cwork->bss_removed = 1;
198 }
199
200
wpa_bss_remove(struct wpa_supplicant * wpa_s,struct wpa_bss * bss,const char * reason)201 static void wpa_bss_remove(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
202 const char *reason)
203 {
204 if (wpa_s->last_scan_res) {
205 unsigned int i;
206 for (i = 0; i < wpa_s->last_scan_res_used; i++) {
207 if (wpa_s->last_scan_res[i] == bss) {
208 os_memmove(&wpa_s->last_scan_res[i],
209 &wpa_s->last_scan_res[i + 1],
210 (wpa_s->last_scan_res_used - i - 1)
211 * sizeof(struct wpa_bss *));
212 wpa_s->last_scan_res_used--;
213 break;
214 }
215 }
216 }
217 wpa_bss_update_pending_connect(wpa_s, bss, NULL);
218 dl_list_del(&bss->list);
219 dl_list_del(&bss->list_id);
220 wpa_s->num_bss--;
221 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR
222 " SSID '%s' due to %s", bss->id, MAC2STR(bss->bssid),
223 wpa_ssid_txt(bss->ssid, bss->ssid_len), reason);
224 wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id);
225 wpa_bss_anqp_free(bss->anqp);
226 os_free(bss);
227 }
228
229
230 /**
231 * wpa_bss_get - Fetch a BSS table entry based on BSSID and SSID
232 * @wpa_s: Pointer to wpa_supplicant data
233 * @bssid: BSSID
234 * @ssid: SSID
235 * @ssid_len: Length of @ssid
236 * Returns: Pointer to the BSS entry or %NULL if not found
237 */
wpa_bss_get(struct wpa_supplicant * wpa_s,const u8 * bssid,const u8 * ssid,size_t ssid_len)238 struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid,
239 const u8 *ssid, size_t ssid_len)
240 {
241 struct wpa_bss *bss;
242 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
243 return NULL;
244 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
245 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
246 bss->ssid_len == ssid_len &&
247 os_memcmp(bss->ssid, ssid, ssid_len) == 0)
248 return bss;
249 }
250 return NULL;
251 }
252
253
calculate_update_time(const struct os_reltime * fetch_time,unsigned int age_ms,struct os_reltime * update_time)254 static void calculate_update_time(const struct os_reltime *fetch_time,
255 unsigned int age_ms,
256 struct os_reltime *update_time)
257 {
258 os_time_t usec;
259
260 update_time->sec = fetch_time->sec;
261 update_time->usec = fetch_time->usec;
262 update_time->sec -= age_ms / 1000;
263 usec = (age_ms % 1000) * 1000;
264 if (update_time->usec < usec) {
265 update_time->sec--;
266 update_time->usec += 1000000;
267 }
268 update_time->usec -= usec;
269 }
270
271
wpa_bss_copy_res(struct wpa_bss * dst,struct wpa_scan_res * src,struct os_reltime * fetch_time)272 static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src,
273 struct os_reltime *fetch_time)
274 {
275 dst->flags = src->flags;
276 os_memcpy(dst->bssid, src->bssid, ETH_ALEN);
277 dst->freq = src->freq;
278 dst->beacon_int = src->beacon_int;
279 dst->caps = src->caps;
280 dst->qual = src->qual;
281 dst->noise = src->noise;
282 dst->level = src->level;
283 dst->tsf = src->tsf;
284 dst->est_throughput = src->est_throughput;
285 dst->snr = src->snr;
286
287 calculate_update_time(fetch_time, src->age, &dst->last_update);
288 }
289
290
wpa_bss_known(struct wpa_supplicant * wpa_s,struct wpa_bss * bss)291 static int wpa_bss_known(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
292 {
293 struct wpa_ssid *ssid;
294
295 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
296 if (ssid->ssid == NULL || ssid->ssid_len == 0)
297 continue;
298 if (ssid->ssid_len == bss->ssid_len &&
299 os_memcmp(ssid->ssid, bss->ssid, ssid->ssid_len) == 0)
300 return 1;
301 }
302
303 return 0;
304 }
305
306
wpa_bss_in_use(struct wpa_supplicant * wpa_s,struct wpa_bss * bss)307 static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
308 {
309 if (bss == wpa_s->current_bss)
310 return 1;
311
312 if (wpa_s->current_bss &&
313 (bss->ssid_len != wpa_s->current_bss->ssid_len ||
314 os_memcmp(bss->ssid, wpa_s->current_bss->ssid,
315 bss->ssid_len) != 0))
316 return 0; /* SSID has changed */
317
318 return !is_zero_ether_addr(bss->bssid) &&
319 (os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 ||
320 os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0);
321 }
322
323
wpa_bss_remove_oldest_unknown(struct wpa_supplicant * wpa_s)324 static int wpa_bss_remove_oldest_unknown(struct wpa_supplicant *wpa_s)
325 {
326 struct wpa_bss *bss;
327
328 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
329 if (!wpa_bss_known(wpa_s, bss)) {
330 wpa_bss_remove(wpa_s, bss, __func__);
331 return 0;
332 }
333 }
334
335 return -1;
336 }
337
338
wpa_bss_remove_oldest(struct wpa_supplicant * wpa_s)339 static int wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s)
340 {
341 struct wpa_bss *bss;
342
343 /*
344 * Remove the oldest entry that does not match with any configured
345 * network.
346 */
347 if (wpa_bss_remove_oldest_unknown(wpa_s) == 0)
348 return 0;
349
350 /*
351 * Remove the oldest entry that isn't currently in use.
352 */
353 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
354 if (!wpa_bss_in_use(wpa_s, bss)) {
355 wpa_bss_remove(wpa_s, bss, __func__);
356 return 0;
357 }
358 }
359
360 return -1;
361 }
362
363
wpa_bss_add(struct wpa_supplicant * wpa_s,const u8 * ssid,size_t ssid_len,struct wpa_scan_res * res,struct os_reltime * fetch_time)364 static struct wpa_bss * wpa_bss_add(struct wpa_supplicant *wpa_s,
365 const u8 *ssid, size_t ssid_len,
366 struct wpa_scan_res *res,
367 struct os_reltime *fetch_time)
368 {
369 struct wpa_bss *bss;
370
371 bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len);
372 if (bss == NULL)
373 return NULL;
374 bss->id = wpa_s->bss_next_id++;
375 bss->last_update_idx = wpa_s->bss_update_idx;
376 wpa_bss_copy_res(bss, res, fetch_time);
377 os_memcpy(bss->ssid, ssid, ssid_len);
378 bss->ssid_len = ssid_len;
379 bss->ie_len = res->ie_len;
380 bss->beacon_ie_len = res->beacon_ie_len;
381 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
382 wpa_bss_set_hessid(bss);
383
384 if (wpa_s->num_bss + 1 > wpa_s->conf->bss_max_count &&
385 wpa_bss_remove_oldest(wpa_s) != 0) {
386 wpa_printf(MSG_ERROR, "Increasing the MAX BSS count to %d "
387 "because all BSSes are in use. We should normally "
388 "not get here!", (int) wpa_s->num_bss + 1);
389 wpa_s->conf->bss_max_count = wpa_s->num_bss + 1;
390 }
391
392 dl_list_add_tail(&wpa_s->bss, &bss->list);
393 dl_list_add_tail(&wpa_s->bss_id, &bss->list_id);
394 wpa_s->num_bss++;
395 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR
396 " SSID '%s' freq %d",
397 bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len),
398 bss->freq);
399 wpas_notify_bss_added(wpa_s, bss->bssid, bss->id);
400 return bss;
401 }
402
403
are_ies_equal(const struct wpa_bss * old,const struct wpa_scan_res * new_res,u32 ie)404 static int are_ies_equal(const struct wpa_bss *old,
405 const struct wpa_scan_res *new_res, u32 ie)
406 {
407 const u8 *old_ie, *new_ie;
408 struct wpabuf *old_ie_buff = NULL;
409 struct wpabuf *new_ie_buff = NULL;
410 int new_ie_len, old_ie_len, ret, is_multi;
411
412 switch (ie) {
413 case WPA_IE_VENDOR_TYPE:
414 old_ie = wpa_bss_get_vendor_ie(old, ie);
415 new_ie = wpa_scan_get_vendor_ie(new_res, ie);
416 is_multi = 0;
417 break;
418 case WPS_IE_VENDOR_TYPE:
419 old_ie_buff = wpa_bss_get_vendor_ie_multi(old, ie);
420 new_ie_buff = wpa_scan_get_vendor_ie_multi(new_res, ie);
421 is_multi = 1;
422 break;
423 case WLAN_EID_RSN:
424 case WLAN_EID_SUPP_RATES:
425 case WLAN_EID_EXT_SUPP_RATES:
426 old_ie = wpa_bss_get_ie(old, ie);
427 new_ie = wpa_scan_get_ie(new_res, ie);
428 is_multi = 0;
429 break;
430 default:
431 wpa_printf(MSG_DEBUG, "bss: %s: cannot compare IEs", __func__);
432 return 0;
433 }
434
435 if (is_multi) {
436 /* in case of multiple IEs stored in buffer */
437 old_ie = old_ie_buff ? wpabuf_head_u8(old_ie_buff) : NULL;
438 new_ie = new_ie_buff ? wpabuf_head_u8(new_ie_buff) : NULL;
439 old_ie_len = old_ie_buff ? wpabuf_len(old_ie_buff) : 0;
440 new_ie_len = new_ie_buff ? wpabuf_len(new_ie_buff) : 0;
441 } else {
442 /* in case of single IE */
443 old_ie_len = old_ie ? old_ie[1] + 2 : 0;
444 new_ie_len = new_ie ? new_ie[1] + 2 : 0;
445 }
446
447 if (!old_ie || !new_ie)
448 ret = !old_ie && !new_ie;
449 else
450 ret = (old_ie_len == new_ie_len &&
451 os_memcmp(old_ie, new_ie, old_ie_len) == 0);
452
453 wpabuf_free(old_ie_buff);
454 wpabuf_free(new_ie_buff);
455
456 return ret;
457 }
458
459
wpa_bss_compare_res(const struct wpa_bss * old,const struct wpa_scan_res * new_res)460 static u32 wpa_bss_compare_res(const struct wpa_bss *old,
461 const struct wpa_scan_res *new_res)
462 {
463 u32 changes = 0;
464 int caps_diff = old->caps ^ new_res->caps;
465
466 if (old->freq != new_res->freq)
467 changes |= WPA_BSS_FREQ_CHANGED_FLAG;
468
469 if (old->level != new_res->level)
470 changes |= WPA_BSS_SIGNAL_CHANGED_FLAG;
471
472 if (caps_diff & IEEE80211_CAP_PRIVACY)
473 changes |= WPA_BSS_PRIVACY_CHANGED_FLAG;
474
475 if (caps_diff & IEEE80211_CAP_IBSS)
476 changes |= WPA_BSS_MODE_CHANGED_FLAG;
477
478 if (old->ie_len == new_res->ie_len &&
479 os_memcmp(old + 1, new_res + 1, old->ie_len) == 0)
480 return changes;
481 changes |= WPA_BSS_IES_CHANGED_FLAG;
482
483 if (!are_ies_equal(old, new_res, WPA_IE_VENDOR_TYPE))
484 changes |= WPA_BSS_WPAIE_CHANGED_FLAG;
485
486 if (!are_ies_equal(old, new_res, WLAN_EID_RSN))
487 changes |= WPA_BSS_RSNIE_CHANGED_FLAG;
488
489 if (!are_ies_equal(old, new_res, WPS_IE_VENDOR_TYPE))
490 changes |= WPA_BSS_WPS_CHANGED_FLAG;
491
492 if (!are_ies_equal(old, new_res, WLAN_EID_SUPP_RATES) ||
493 !are_ies_equal(old, new_res, WLAN_EID_EXT_SUPP_RATES))
494 changes |= WPA_BSS_RATES_CHANGED_FLAG;
495
496 return changes;
497 }
498
499
notify_bss_changes(struct wpa_supplicant * wpa_s,u32 changes,const struct wpa_bss * bss)500 static void notify_bss_changes(struct wpa_supplicant *wpa_s, u32 changes,
501 const struct wpa_bss *bss)
502 {
503 if (changes & WPA_BSS_FREQ_CHANGED_FLAG)
504 wpas_notify_bss_freq_changed(wpa_s, bss->id);
505
506 if (changes & WPA_BSS_SIGNAL_CHANGED_FLAG)
507 wpas_notify_bss_signal_changed(wpa_s, bss->id);
508
509 if (changes & WPA_BSS_PRIVACY_CHANGED_FLAG)
510 wpas_notify_bss_privacy_changed(wpa_s, bss->id);
511
512 if (changes & WPA_BSS_MODE_CHANGED_FLAG)
513 wpas_notify_bss_mode_changed(wpa_s, bss->id);
514
515 if (changes & WPA_BSS_WPAIE_CHANGED_FLAG)
516 wpas_notify_bss_wpaie_changed(wpa_s, bss->id);
517
518 if (changes & WPA_BSS_RSNIE_CHANGED_FLAG)
519 wpas_notify_bss_rsnie_changed(wpa_s, bss->id);
520
521 if (changes & WPA_BSS_WPS_CHANGED_FLAG)
522 wpas_notify_bss_wps_changed(wpa_s, bss->id);
523
524 if (changes & WPA_BSS_IES_CHANGED_FLAG)
525 wpas_notify_bss_ies_changed(wpa_s, bss->id);
526
527 if (changes & WPA_BSS_RATES_CHANGED_FLAG)
528 wpas_notify_bss_rates_changed(wpa_s, bss->id);
529
530 wpas_notify_bss_seen(wpa_s, bss->id);
531 }
532
533
534 static struct wpa_bss *
wpa_bss_update(struct wpa_supplicant * wpa_s,struct wpa_bss * bss,struct wpa_scan_res * res,struct os_reltime * fetch_time)535 wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
536 struct wpa_scan_res *res, struct os_reltime *fetch_time)
537 {
538 u32 changes;
539
540 changes = wpa_bss_compare_res(bss, res);
541 if (changes & WPA_BSS_FREQ_CHANGED_FLAG)
542 wpa_printf(MSG_DEBUG, "BSS: " MACSTR " changed freq %d --> %d",
543 MAC2STR(bss->bssid), bss->freq, res->freq);
544 bss->scan_miss_count = 0;
545 bss->last_update_idx = wpa_s->bss_update_idx;
546 wpa_bss_copy_res(bss, res, fetch_time);
547 /* Move the entry to the end of the list */
548 dl_list_del(&bss->list);
549 #ifdef CONFIG_P2P
550 if (wpa_bss_get_vendor_ie(bss, P2P_IE_VENDOR_TYPE) &&
551 !wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE)) {
552 /*
553 * This can happen when non-P2P station interface runs a scan
554 * without P2P IE in the Probe Request frame. P2P GO would reply
555 * to that with a Probe Response that does not include P2P IE.
556 * Do not update the IEs in this BSS entry to avoid such loss of
557 * information that may be needed for P2P operations to
558 * determine group information.
559 */
560 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Do not update scan IEs for "
561 MACSTR " since that would remove P2P IE information",
562 MAC2STR(bss->bssid));
563 } else
564 #endif /* CONFIG_P2P */
565 if (bss->ie_len + bss->beacon_ie_len >=
566 res->ie_len + res->beacon_ie_len) {
567 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
568 bss->ie_len = res->ie_len;
569 bss->beacon_ie_len = res->beacon_ie_len;
570 } else {
571 struct wpa_bss *nbss;
572 struct dl_list *prev = bss->list_id.prev;
573 dl_list_del(&bss->list_id);
574 nbss = os_realloc(bss, sizeof(*bss) + res->ie_len +
575 res->beacon_ie_len);
576 if (nbss) {
577 unsigned int i;
578 for (i = 0; i < wpa_s->last_scan_res_used; i++) {
579 if (wpa_s->last_scan_res[i] == bss) {
580 wpa_s->last_scan_res[i] = nbss;
581 break;
582 }
583 }
584 if (wpa_s->current_bss == bss)
585 wpa_s->current_bss = nbss;
586 wpa_bss_update_pending_connect(wpa_s, bss, nbss);
587 bss = nbss;
588 os_memcpy(bss + 1, res + 1,
589 res->ie_len + res->beacon_ie_len);
590 bss->ie_len = res->ie_len;
591 bss->beacon_ie_len = res->beacon_ie_len;
592 }
593 dl_list_add(prev, &bss->list_id);
594 }
595 if (changes & WPA_BSS_IES_CHANGED_FLAG)
596 wpa_bss_set_hessid(bss);
597 dl_list_add_tail(&wpa_s->bss, &bss->list);
598
599 notify_bss_changes(wpa_s, changes, bss);
600
601 return bss;
602 }
603
604
605 /**
606 * wpa_bss_update_start - Start a BSS table update from scan results
607 * @wpa_s: Pointer to wpa_supplicant data
608 *
609 * This function is called at the start of each BSS table update round for new
610 * scan results. The actual scan result entries are indicated with calls to
611 * wpa_bss_update_scan_res() and the update round is finished with a call to
612 * wpa_bss_update_end().
613 */
wpa_bss_update_start(struct wpa_supplicant * wpa_s)614 void wpa_bss_update_start(struct wpa_supplicant *wpa_s)
615 {
616 wpa_s->bss_update_idx++;
617 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Start scan result update %u",
618 wpa_s->bss_update_idx);
619 wpa_s->last_scan_res_used = 0;
620 }
621
622
623 /**
624 * wpa_bss_update_scan_res - Update a BSS table entry based on a scan result
625 * @wpa_s: Pointer to wpa_supplicant data
626 * @res: Scan result
627 * @fetch_time: Time when the result was fetched from the driver
628 *
629 * This function updates a BSS table entry (or adds one) based on a scan result.
630 * This is called separately for each scan result between the calls to
631 * wpa_bss_update_start() and wpa_bss_update_end().
632 */
wpa_bss_update_scan_res(struct wpa_supplicant * wpa_s,struct wpa_scan_res * res,struct os_reltime * fetch_time)633 void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s,
634 struct wpa_scan_res *res,
635 struct os_reltime *fetch_time)
636 {
637 const u8 *ssid, *p2p, *mesh;
638 struct wpa_bss *bss;
639
640 if (wpa_s->conf->ignore_old_scan_res) {
641 struct os_reltime update;
642 calculate_update_time(fetch_time, res->age, &update);
643 if (os_reltime_before(&update, &wpa_s->scan_trigger_time)) {
644 struct os_reltime age;
645 os_reltime_sub(&wpa_s->scan_trigger_time, &update,
646 &age);
647 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Ignore driver BSS "
648 "table entry that is %u.%06u seconds older "
649 "than our scan trigger",
650 (unsigned int) age.sec,
651 (unsigned int) age.usec);
652 return;
653 }
654 }
655
656 ssid = wpa_scan_get_ie(res, WLAN_EID_SSID);
657 if (ssid == NULL) {
658 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: No SSID IE included for "
659 MACSTR, MAC2STR(res->bssid));
660 return;
661 }
662 if (ssid[1] > SSID_MAX_LEN) {
663 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Too long SSID IE included for "
664 MACSTR, MAC2STR(res->bssid));
665 return;
666 }
667
668 p2p = wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE);
669 #ifdef CONFIG_P2P
670 if (p2p == NULL &&
671 wpa_s->p2p_group_interface != NOT_P2P_GROUP_INTERFACE) {
672 /*
673 * If it's a P2P specific interface, then don't update
674 * the scan result without a P2P IE.
675 */
676 wpa_printf(MSG_DEBUG, "BSS: No P2P IE - skipping BSS " MACSTR
677 " update for P2P interface", MAC2STR(res->bssid));
678 return;
679 }
680 #endif /* CONFIG_P2P */
681 if (p2p && ssid[1] == P2P_WILDCARD_SSID_LEN &&
682 os_memcmp(ssid + 2, P2P_WILDCARD_SSID, P2P_WILDCARD_SSID_LEN) == 0)
683 return; /* Skip P2P listen discovery results here */
684
685 /* TODO: add option for ignoring BSSes we are not interested in
686 * (to save memory) */
687
688 mesh = wpa_scan_get_ie(res, WLAN_EID_MESH_ID);
689 if (mesh && mesh[1] <= SSID_MAX_LEN)
690 ssid = mesh;
691
692 bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]);
693 if (bss == NULL)
694 bss = wpa_bss_add(wpa_s, ssid + 2, ssid[1], res, fetch_time);
695 else {
696 bss = wpa_bss_update(wpa_s, bss, res, fetch_time);
697 if (wpa_s->last_scan_res) {
698 unsigned int i;
699 for (i = 0; i < wpa_s->last_scan_res_used; i++) {
700 if (bss == wpa_s->last_scan_res[i]) {
701 /* Already in the list */
702 return;
703 }
704 }
705 }
706 }
707
708 if (bss == NULL)
709 return;
710 if (wpa_s->last_scan_res_used >= wpa_s->last_scan_res_size) {
711 struct wpa_bss **n;
712 unsigned int siz;
713 if (wpa_s->last_scan_res_size == 0)
714 siz = 32;
715 else
716 siz = wpa_s->last_scan_res_size * 2;
717 n = os_realloc_array(wpa_s->last_scan_res, siz,
718 sizeof(struct wpa_bss *));
719 if (n == NULL)
720 return;
721 wpa_s->last_scan_res = n;
722 wpa_s->last_scan_res_size = siz;
723 }
724
725 if (wpa_s->last_scan_res)
726 wpa_s->last_scan_res[wpa_s->last_scan_res_used++] = bss;
727 }
728
729
wpa_bss_included_in_scan(const struct wpa_bss * bss,const struct scan_info * info)730 static int wpa_bss_included_in_scan(const struct wpa_bss *bss,
731 const struct scan_info *info)
732 {
733 int found;
734 size_t i;
735
736 if (info == NULL)
737 return 1;
738
739 if (info->num_freqs) {
740 found = 0;
741 for (i = 0; i < info->num_freqs; i++) {
742 if (bss->freq == info->freqs[i]) {
743 found = 1;
744 break;
745 }
746 }
747 if (!found)
748 return 0;
749 }
750
751 if (info->num_ssids) {
752 found = 0;
753 for (i = 0; i < info->num_ssids; i++) {
754 const struct wpa_driver_scan_ssid *s = &info->ssids[i];
755 if ((s->ssid == NULL || s->ssid_len == 0) ||
756 (s->ssid_len == bss->ssid_len &&
757 os_memcmp(s->ssid, bss->ssid, bss->ssid_len) ==
758 0)) {
759 found = 1;
760 break;
761 }
762 }
763 if (!found)
764 return 0;
765 }
766
767 return 1;
768 }
769
770
771 /**
772 * wpa_bss_update_end - End a BSS table update from scan results
773 * @wpa_s: Pointer to wpa_supplicant data
774 * @info: Information about scan parameters
775 * @new_scan: Whether this update round was based on a new scan
776 *
777 * This function is called at the end of each BSS table update round for new
778 * scan results. The start of the update was indicated with a call to
779 * wpa_bss_update_start().
780 */
wpa_bss_update_end(struct wpa_supplicant * wpa_s,struct scan_info * info,int new_scan)781 void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info,
782 int new_scan)
783 {
784 struct wpa_bss *bss, *n;
785
786 os_get_reltime(&wpa_s->last_scan);
787 if (!new_scan)
788 return; /* do not expire entries without new scan */
789
790 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
791 if (wpa_bss_in_use(wpa_s, bss))
792 continue;
793 if (!wpa_bss_included_in_scan(bss, info))
794 continue; /* expire only BSSes that were scanned */
795 if (bss->last_update_idx < wpa_s->bss_update_idx)
796 bss->scan_miss_count++;
797 if (bss->scan_miss_count >=
798 wpa_s->conf->bss_expiration_scan_count) {
799 wpa_bss_remove(wpa_s, bss, "no match in scan");
800 }
801 }
802
803 wpa_printf(MSG_DEBUG, "BSS: last_scan_res_used=%u/%u",
804 wpa_s->last_scan_res_used, wpa_s->last_scan_res_size);
805 }
806
807
808 /**
809 * wpa_bss_flush_by_age - Flush old BSS entries
810 * @wpa_s: Pointer to wpa_supplicant data
811 * @age: Maximum entry age in seconds
812 *
813 * Remove BSS entries that have not been updated during the last @age seconds.
814 */
wpa_bss_flush_by_age(struct wpa_supplicant * wpa_s,int age)815 void wpa_bss_flush_by_age(struct wpa_supplicant *wpa_s, int age)
816 {
817 struct wpa_bss *bss, *n;
818 struct os_reltime t;
819
820 if (dl_list_empty(&wpa_s->bss))
821 return;
822
823 os_get_reltime(&t);
824 t.sec -= age;
825
826 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
827 if (wpa_bss_in_use(wpa_s, bss))
828 continue;
829
830 if (os_reltime_before(&bss->last_update, &t)) {
831 wpa_bss_remove(wpa_s, bss, __func__);
832 } else
833 break;
834 }
835 }
836
837
838 /**
839 * wpa_bss_init - Initialize BSS table
840 * @wpa_s: Pointer to wpa_supplicant data
841 * Returns: 0 on success, -1 on failure
842 *
843 * This prepares BSS table lists and timer for periodic updates. The BSS table
844 * is deinitialized with wpa_bss_deinit() once not needed anymore.
845 */
wpa_bss_init(struct wpa_supplicant * wpa_s)846 int wpa_bss_init(struct wpa_supplicant *wpa_s)
847 {
848 dl_list_init(&wpa_s->bss);
849 dl_list_init(&wpa_s->bss_id);
850 return 0;
851 }
852
853
854 /**
855 * wpa_bss_flush - Flush all unused BSS entries
856 * @wpa_s: Pointer to wpa_supplicant data
857 */
wpa_bss_flush(struct wpa_supplicant * wpa_s)858 void wpa_bss_flush(struct wpa_supplicant *wpa_s)
859 {
860 struct wpa_bss *bss, *n;
861
862 wpa_s->clear_driver_scan_cache = 1;
863
864 if (wpa_s->bss.next == NULL)
865 return; /* BSS table not yet initialized */
866
867 dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
868 if (wpa_bss_in_use(wpa_s, bss))
869 continue;
870 wpa_bss_remove(wpa_s, bss, __func__);
871 }
872 }
873
874
875 /**
876 * wpa_bss_deinit - Deinitialize BSS table
877 * @wpa_s: Pointer to wpa_supplicant data
878 */
wpa_bss_deinit(struct wpa_supplicant * wpa_s)879 void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
880 {
881 wpa_bss_flush(wpa_s);
882 }
883
884
885 /**
886 * wpa_bss_get_bssid - Fetch a BSS table entry based on BSSID
887 * @wpa_s: Pointer to wpa_supplicant data
888 * @bssid: BSSID
889 * Returns: Pointer to the BSS entry or %NULL if not found
890 */
wpa_bss_get_bssid(struct wpa_supplicant * wpa_s,const u8 * bssid)891 struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
892 const u8 *bssid)
893 {
894 struct wpa_bss *bss;
895 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
896 return NULL;
897 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
898 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
899 return bss;
900 }
901 return NULL;
902 }
903
904
905 /**
906 * wpa_bss_get_bssid_latest - Fetch the latest BSS table entry based on BSSID
907 * @wpa_s: Pointer to wpa_supplicant data
908 * @bssid: BSSID
909 * Returns: Pointer to the BSS entry or %NULL if not found
910 *
911 * This function is like wpa_bss_get_bssid(), but full BSS table is iterated to
912 * find the entry that has the most recent update. This can help in finding the
913 * correct entry in cases where the SSID of the AP may have changed recently
914 * (e.g., in WPS reconfiguration cases).
915 */
wpa_bss_get_bssid_latest(struct wpa_supplicant * wpa_s,const u8 * bssid)916 struct wpa_bss * wpa_bss_get_bssid_latest(struct wpa_supplicant *wpa_s,
917 const u8 *bssid)
918 {
919 struct wpa_bss *bss, *found = NULL;
920 if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
921 return NULL;
922 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
923 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) != 0)
924 continue;
925 if (found == NULL ||
926 os_reltime_before(&found->last_update, &bss->last_update))
927 found = bss;
928 }
929 return found;
930 }
931
932
933 #ifdef CONFIG_P2P
934 /**
935 * wpa_bss_get_p2p_dev_addr - Fetch a BSS table entry based on P2P Device Addr
936 * @wpa_s: Pointer to wpa_supplicant data
937 * @dev_addr: P2P Device Address of the GO
938 * Returns: Pointer to the BSS entry or %NULL if not found
939 */
wpa_bss_get_p2p_dev_addr(struct wpa_supplicant * wpa_s,const u8 * dev_addr)940 struct wpa_bss * wpa_bss_get_p2p_dev_addr(struct wpa_supplicant *wpa_s,
941 const u8 *dev_addr)
942 {
943 struct wpa_bss *bss;
944 dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
945 u8 addr[ETH_ALEN];
946 if (p2p_parse_dev_addr((const u8 *) (bss + 1), bss->ie_len,
947 addr) == 0 &&
948 os_memcmp(addr, dev_addr, ETH_ALEN) == 0)
949 return bss;
950 }
951 return NULL;
952 }
953 #endif /* CONFIG_P2P */
954
955
956 /**
957 * wpa_bss_get_id - Fetch a BSS table entry based on identifier
958 * @wpa_s: Pointer to wpa_supplicant data
959 * @id: Unique identifier (struct wpa_bss::id) assigned for the entry
960 * Returns: Pointer to the BSS entry or %NULL if not found
961 */
wpa_bss_get_id(struct wpa_supplicant * wpa_s,unsigned int id)962 struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id)
963 {
964 struct wpa_bss *bss;
965 dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
966 if (bss->id == id)
967 return bss;
968 }
969 return NULL;
970 }
971
972
973 /**
974 * wpa_bss_get_id_range - Fetch a BSS table entry based on identifier range
975 * @wpa_s: Pointer to wpa_supplicant data
976 * @idf: Smallest allowed identifier assigned for the entry
977 * @idf: Largest allowed identifier assigned for the entry
978 * Returns: Pointer to the BSS entry or %NULL if not found
979 *
980 * This function is similar to wpa_bss_get_id() but allows a BSS entry with the
981 * smallest id value to be fetched within the specified range without the
982 * caller having to know the exact id.
983 */
wpa_bss_get_id_range(struct wpa_supplicant * wpa_s,unsigned int idf,unsigned int idl)984 struct wpa_bss * wpa_bss_get_id_range(struct wpa_supplicant *wpa_s,
985 unsigned int idf, unsigned int idl)
986 {
987 struct wpa_bss *bss;
988 dl_list_for_each(bss, &wpa_s->bss_id, struct wpa_bss, list_id) {
989 if (bss->id >= idf && bss->id <= idl)
990 return bss;
991 }
992 return NULL;
993 }
994
995
996 /**
997 * wpa_bss_get_ie - Fetch a specified information element from a BSS entry
998 * @bss: BSS table entry
999 * @ie: Information element identitifier (WLAN_EID_*)
1000 * Returns: Pointer to the information element (id field) or %NULL if not found
1001 *
1002 * This function returns the first matching information element in the BSS
1003 * entry.
1004 */
wpa_bss_get_ie(const struct wpa_bss * bss,u8 ie)1005 const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie)
1006 {
1007 const u8 *end, *pos;
1008
1009 pos = (const u8 *) (bss + 1);
1010 end = pos + bss->ie_len;
1011
1012 while (pos + 1 < end) {
1013 if (pos + 2 + pos[1] > end)
1014 break;
1015 if (pos[0] == ie)
1016 return pos;
1017 pos += 2 + pos[1];
1018 }
1019
1020 return NULL;
1021 }
1022
1023
1024 /**
1025 * wpa_bss_get_vendor_ie - Fetch a vendor information element from a BSS entry
1026 * @bss: BSS table entry
1027 * @vendor_type: Vendor type (four octets starting the IE payload)
1028 * Returns: Pointer to the information element (id field) or %NULL if not found
1029 *
1030 * This function returns the first matching information element in the BSS
1031 * entry.
1032 */
wpa_bss_get_vendor_ie(const struct wpa_bss * bss,u32 vendor_type)1033 const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type)
1034 {
1035 const u8 *end, *pos;
1036
1037 pos = (const u8 *) (bss + 1);
1038 end = pos + bss->ie_len;
1039
1040 while (pos + 1 < end) {
1041 if (pos + 2 + pos[1] > end)
1042 break;
1043 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1044 vendor_type == WPA_GET_BE32(&pos[2]))
1045 return pos;
1046 pos += 2 + pos[1];
1047 }
1048
1049 return NULL;
1050 }
1051
1052
1053 /**
1054 * wpa_bss_get_vendor_ie_beacon - Fetch a vendor information from a BSS entry
1055 * @bss: BSS table entry
1056 * @vendor_type: Vendor type (four octets starting the IE payload)
1057 * Returns: Pointer to the information element (id field) or %NULL if not found
1058 *
1059 * This function returns the first matching information element in the BSS
1060 * entry.
1061 *
1062 * This function is like wpa_bss_get_vendor_ie(), but uses IE buffer only
1063 * from Beacon frames instead of either Beacon or Probe Response frames.
1064 */
wpa_bss_get_vendor_ie_beacon(const struct wpa_bss * bss,u32 vendor_type)1065 const u8 * wpa_bss_get_vendor_ie_beacon(const struct wpa_bss *bss,
1066 u32 vendor_type)
1067 {
1068 const u8 *end, *pos;
1069
1070 if (bss->beacon_ie_len == 0)
1071 return NULL;
1072
1073 pos = (const u8 *) (bss + 1);
1074 pos += bss->ie_len;
1075 end = pos + bss->beacon_ie_len;
1076
1077 while (pos + 1 < end) {
1078 if (pos + 2 + pos[1] > end)
1079 break;
1080 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1081 vendor_type == WPA_GET_BE32(&pos[2]))
1082 return pos;
1083 pos += 2 + pos[1];
1084 }
1085
1086 return NULL;
1087 }
1088
1089
1090 /**
1091 * wpa_bss_get_vendor_ie_multi - Fetch vendor IE data from a BSS entry
1092 * @bss: BSS table entry
1093 * @vendor_type: Vendor type (four octets starting the IE payload)
1094 * Returns: Pointer to the information element payload or %NULL if not found
1095 *
1096 * This function returns concatenated payload of possibly fragmented vendor
1097 * specific information elements in the BSS entry. The caller is responsible for
1098 * freeing the returned buffer.
1099 */
wpa_bss_get_vendor_ie_multi(const struct wpa_bss * bss,u32 vendor_type)1100 struct wpabuf * wpa_bss_get_vendor_ie_multi(const struct wpa_bss *bss,
1101 u32 vendor_type)
1102 {
1103 struct wpabuf *buf;
1104 const u8 *end, *pos;
1105
1106 buf = wpabuf_alloc(bss->ie_len);
1107 if (buf == NULL)
1108 return NULL;
1109
1110 pos = (const u8 *) (bss + 1);
1111 end = pos + bss->ie_len;
1112
1113 while (pos + 1 < end) {
1114 if (pos + 2 + pos[1] > end)
1115 break;
1116 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1117 vendor_type == WPA_GET_BE32(&pos[2]))
1118 wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1119 pos += 2 + pos[1];
1120 }
1121
1122 if (wpabuf_len(buf) == 0) {
1123 wpabuf_free(buf);
1124 buf = NULL;
1125 }
1126
1127 return buf;
1128 }
1129
1130
1131 /**
1132 * wpa_bss_get_vendor_ie_multi_beacon - Fetch vendor IE data from a BSS entry
1133 * @bss: BSS table entry
1134 * @vendor_type: Vendor type (four octets starting the IE payload)
1135 * Returns: Pointer to the information element payload or %NULL if not found
1136 *
1137 * This function returns concatenated payload of possibly fragmented vendor
1138 * specific information elements in the BSS entry. The caller is responsible for
1139 * freeing the returned buffer.
1140 *
1141 * This function is like wpa_bss_get_vendor_ie_multi(), but uses IE buffer only
1142 * from Beacon frames instead of either Beacon or Probe Response frames.
1143 */
wpa_bss_get_vendor_ie_multi_beacon(const struct wpa_bss * bss,u32 vendor_type)1144 struct wpabuf * wpa_bss_get_vendor_ie_multi_beacon(const struct wpa_bss *bss,
1145 u32 vendor_type)
1146 {
1147 struct wpabuf *buf;
1148 const u8 *end, *pos;
1149
1150 buf = wpabuf_alloc(bss->beacon_ie_len);
1151 if (buf == NULL)
1152 return NULL;
1153
1154 pos = (const u8 *) (bss + 1);
1155 pos += bss->ie_len;
1156 end = pos + bss->beacon_ie_len;
1157
1158 while (pos + 1 < end) {
1159 if (pos + 2 + pos[1] > end)
1160 break;
1161 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1162 vendor_type == WPA_GET_BE32(&pos[2]))
1163 wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1164 pos += 2 + pos[1];
1165 }
1166
1167 if (wpabuf_len(buf) == 0) {
1168 wpabuf_free(buf);
1169 buf = NULL;
1170 }
1171
1172 return buf;
1173 }
1174
1175
1176 /**
1177 * wpa_bss_get_max_rate - Get maximum legacy TX rate supported in a BSS
1178 * @bss: BSS table entry
1179 * Returns: Maximum legacy rate in units of 500 kbps
1180 */
wpa_bss_get_max_rate(const struct wpa_bss * bss)1181 int wpa_bss_get_max_rate(const struct wpa_bss *bss)
1182 {
1183 int rate = 0;
1184 const u8 *ie;
1185 int i;
1186
1187 ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
1188 for (i = 0; ie && i < ie[1]; i++) {
1189 if ((ie[i + 2] & 0x7f) > rate)
1190 rate = ie[i + 2] & 0x7f;
1191 }
1192
1193 ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
1194 for (i = 0; ie && i < ie[1]; i++) {
1195 if ((ie[i + 2] & 0x7f) > rate)
1196 rate = ie[i + 2] & 0x7f;
1197 }
1198
1199 return rate;
1200 }
1201
1202
1203 /**
1204 * wpa_bss_get_bit_rates - Get legacy TX rates supported in a BSS
1205 * @bss: BSS table entry
1206 * @rates: Buffer for returning a pointer to the rates list (units of 500 kbps)
1207 * Returns: number of legacy TX rates or -1 on failure
1208 *
1209 * The caller is responsible for freeing the returned buffer with os_free() in
1210 * case of success.
1211 */
wpa_bss_get_bit_rates(const struct wpa_bss * bss,u8 ** rates)1212 int wpa_bss_get_bit_rates(const struct wpa_bss *bss, u8 **rates)
1213 {
1214 const u8 *ie, *ie2;
1215 int i, j;
1216 unsigned int len;
1217 u8 *r;
1218
1219 ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
1220 ie2 = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
1221
1222 len = (ie ? ie[1] : 0) + (ie2 ? ie2[1] : 0);
1223
1224 r = os_malloc(len);
1225 if (!r)
1226 return -1;
1227
1228 for (i = 0; ie && i < ie[1]; i++)
1229 r[i] = ie[i + 2] & 0x7f;
1230
1231 for (j = 0; ie2 && j < ie2[1]; j++)
1232 r[i + j] = ie2[j + 2] & 0x7f;
1233
1234 *rates = r;
1235 return len;
1236 }
1237