Outline ![]()
Files ![]()
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
/*
* BSS table
* Copyright (c) 2009-2019, Jouni Malinen <j@w1.fi>
*
* This software may be distributed under the terms of the BSD license.
* See README for more details.
*/
#include "utils/includes.h"
#include "utils/common.h"
#include "common/ieee802_11_defs.h"
#include "common/ieee802_11_common.h"
#include "drivers/driver.h"
#include "eap_peer/eap.h"
#include "wpa_supplicant_i.h"
#include "scan.h"
#include "bss.h"
#ifdef ESP_SUPPLICANT
#include "esp_wifi_driver.h"
#endif
#define MAX_BSS_COUNT 20
void wpa_bss_remove(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
const char *reason)
{
if (wpa_s->last_scan_res) {
unsigned int i;
for (i = 0; i < wpa_s->last_scan_res_used; i++) {
if (wpa_s->last_scan_res[i] == bss) {
os_memmove(&wpa_s->last_scan_res[i],
&wpa_s->last_scan_res[i + 1],
(wpa_s->last_scan_res_used - i - 1)
* sizeof(struct wpa_bss *));
wpa_s->last_scan_res_used--;
break;
}
}
}
dl_list_del(&bss->list);
dl_list_del(&bss->list_id);
wpa_s->num_bss--;
wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR
" SSID '%s' due to %s", bss->id, MAC2STR(bss->bssid),
wpa_ssid_txt(bss->ssid, bss->ssid_len), reason);
os_free(bss);
}
/**
* wpa_bss_get - Fetch a BSS table entry based on BSSID and SSID
* @wpa_s: Pointer to wpa_supplicant data
* @bssid: BSSID
* @ssid: SSID
* @ssid_len: Length of @ssid
* Returns: Pointer to the BSS entry or %NULL if not found
*/
struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid,
const u8 *ssid, size_t ssid_len)
{
struct wpa_bss *bss;
dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
bss->ssid_len == ssid_len &&
os_memcmp(bss->ssid, ssid, ssid_len) == 0)
return bss;
}
return NULL;
}
void calculate_update_time(const struct os_reltime *fetch_time,
unsigned int age_ms,
struct os_reltime *update_time)
{
os_time_t usec;
update_time->sec = fetch_time->sec;
update_time->usec = fetch_time->usec;
update_time->sec -= age_ms / 1000;
usec = (age_ms % 1000) * 1000;
if (update_time->usec < usec) {
update_time->sec--;
update_time->usec += 1000000;
}
update_time->usec -= usec;
}
static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src,
struct os_reltime *fetch_time)
{
dst->flags = src->flags;
os_memcpy(dst->bssid, src->bssid, ETH_ALEN);
dst->channel = src->chan;
dst->beacon_int = src->beacon_int;
dst->caps = src->caps;
dst->noise = src->noise;
dst->level = src->level;
dst->tsf = src->tsf;
dst->parent_tsf = src->parent_tsf;
calculate_update_time(fetch_time, src->age, &dst->last_update);
}
#ifdef ESP_SUPPLICANT
static int wpa_bss_known(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
{
struct wifi_ssid *ssid = esp_wifi_sta_get_prof_ssid_internal();
if (ssid->len == 0)
return 0;
if (ssid->len == bss->ssid_len &&
os_memcmp(ssid->ssid, bss->ssid, ssid->len) == 0)
return 1;
return 0;
}
#endif
static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
{
if (bss == wpa_s->current_bss)
return 1;
#ifndef ESP_SUPPLICANT
if (wpa_s->current_bss &&
(bss->ssid_len != wpa_s->current_bss->ssid_len ||
os_memcmp(bss->ssid, wpa_s->current_bss->ssid,
bss->ssid_len) != 0))
return 0; /* SSID has changed */
return !is_zero_ether_addr(bss->bssid) && wpa_s->current_bss->bssid &&
(os_memcmp(bss->bssid, wpa_s->current_bss->bssid, ETH_ALEN) == 0);
#else
return 0;
#endif
}
static int wpa_bss_remove_oldest_unknown(struct wpa_supplicant *wpa_s)
{
struct wpa_bss *bss;
dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
if (!wpa_bss_known(wpa_s, bss)) {
wpa_bss_remove(wpa_s, bss, __func__);
return 0;
}
}
return -1;
}
static int wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s)
{
struct wpa_bss *bss;
/*
* Remove the oldest entry that does not match with any configured
* network.
*/
if (wpa_bss_remove_oldest_unknown(wpa_s) == 0)
return 0;
/*
* Remove the oldest entry that isn't currently in use.
*/
dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
if (!wpa_bss_in_use(wpa_s, bss)) {
wpa_bss_remove(wpa_s, bss, __func__);
return 0;
}
}
return -1;
}
static struct wpa_bss * 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)
{
struct wpa_bss *bss;
if ((wpa_s->num_bss + 1 > MAX_BSS_COUNT) &&
(wpa_bss_remove_oldest(wpa_s) < 0)) {
wpa_printf(MSG_ERROR,
"Failed to clean older entries, rejecting scan result");
return NULL;
}
bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len);
if (bss == NULL)
return NULL;
bss->id = wpa_s->bss_next_id++;
bss->last_update_idx = wpa_s->bss_update_idx;
wpa_bss_copy_res(bss, res, fetch_time);
os_memcpy(bss->ssid, ssid, ssid_len);
bss->ssid_len = ssid_len;
bss->ie_len = res->ie_len;
bss->beacon_ie_len = res->beacon_ie_len;
os_memcpy(bss->ies, res + 1, res->ie_len + res->beacon_ie_len);
dl_list_add_tail(&wpa_s->bss, &bss->list);
dl_list_add_tail(&wpa_s->bss_id, &bss->list_id);
wpa_s->num_bss++;
wpa_dbg(wpa_s, MSG_INFO, "BSS: Add new id %u BSSID " MACSTR
" SSID '%s' chan %d",
bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len),
bss->channel);
return bss;
}
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)
{
if (bss->last_update_idx == wpa_s->bss_update_idx) {
struct os_reltime update_time;
/*
* Some drivers (e.g., cfg80211) include multiple BSS entries
* for the same BSS if that BSS's channel changes. The BSS list
* implementation in wpa_supplicant does not do that and we need
* to filter out the obsolete results here to make sure only the
* most current BSS information remains in the table.
*/
wpa_printf(MSG_MSGDUMP, "BSS: " MACSTR
" has multiple entries in the scan results - select the most current one",
MAC2STR(bss->bssid));
calculate_update_time(fetch_time, res->age, &update_time);
wpa_printf(MSG_MSGDUMP,
"Accept this BSS entry since it looks more current than the previous update");
}
bss->last_update_idx = wpa_s->bss_update_idx;
wpa_bss_copy_res(bss, res, fetch_time);
/* Move the entry to the end of the list */
dl_list_del(&bss->list);
if (bss->ie_len + bss->beacon_ie_len >=
res->ie_len + res->beacon_ie_len) {
os_memcpy(bss->ies, res + 1, res->ie_len + res->beacon_ie_len);
bss->ie_len = res->ie_len;
bss->beacon_ie_len = res->beacon_ie_len;
} else {
struct wpa_bss *nbss;
struct dl_list *prev = bss->list_id.prev;
dl_list_del(&bss->list_id);
nbss = os_realloc(bss, sizeof(*bss) + res->ie_len +
res->beacon_ie_len);
if (nbss) {
unsigned int i;
for (i = 0; i < wpa_s->last_scan_res_used; i++) {
if (wpa_s->last_scan_res[i] == bss) {
wpa_s->last_scan_res[i] = nbss;
break;
}
}
if (wpa_s->current_bss == bss)
wpa_s->current_bss = nbss;
bss = nbss;
os_memcpy(bss->ies, res + 1,
res->ie_len + res->beacon_ie_len);
bss->ie_len = res->ie_len;
bss->beacon_ie_len = res->beacon_ie_len;
}
dl_list_add(prev, &bss->list_id);
}
dl_list_add_tail(&wpa_s->bss, &bss->list);
return bss;
}
/**
* wpa_bss_update_start - Start a BSS table update from scan results
* @wpa_s: Pointer to wpa_supplicant data
*
* This function is called at the start of each BSS table update round for new
* scan results. The actual scan result entries are indicated with calls to
* wpa_bss_update_scan_res() and the update round is finished with a call to
* wpa_bss_update_end().
*/
void wpa_bss_update_start(struct wpa_supplicant *wpa_s)
{
wpa_s->bss_update_idx++;
wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Start scan result update %u",
wpa_s->bss_update_idx);
wpa_s->last_scan_res_used = 0;
}
/**
* wpa_bss_update_scan_res - Update a BSS table entry based on a scan result
* @wpa_s: Pointer to wpa_supplicant data
* @res: Scan result
* @fetch_time: Time when the result was fetched from the driver
*
* This function updates a BSS table entry (or adds one) based on a scan result.
* This is called separately for each scan result between the calls to
* wpa_bss_update_start() and wpa_bss_update_end().
*/
void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s,
struct wpa_scan_res *res,
struct os_reltime *fetch_time)
{
const u8 *ssid;
struct wpa_bss *bss;
ssid = wpa_scan_get_ie(res, WLAN_EID_SSID);
if (ssid == NULL) {
wpa_dbg(wpa_s, MSG_DEBUG, "BSS: No SSID IE included for "
MACSTR, MAC2STR(res->bssid));
return;
}
if (ssid[1] > SSID_MAX_LEN) {
wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Too long SSID IE included for "
MACSTR, MAC2STR(res->bssid));
return;
}
/* TODO: add option for ignoring BSSes we are not interested in
* (to save memory) */
bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]);
if (bss == NULL)
bss = wpa_bss_add(wpa_s, ssid + 2, ssid[1], res, fetch_time);
else {
bss = wpa_bss_update(wpa_s, bss, res, fetch_time);
if (wpa_s->last_scan_res) {
unsigned int i;
for (i = 0; i < wpa_s->last_scan_res_used; i++) {
if (bss == wpa_s->last_scan_res[i]) {
/* Already in the list */
return;
}
}
}
}
if (bss == NULL)
return;
if (wpa_s->last_scan_res_used >= wpa_s->last_scan_res_size) {
struct wpa_bss **n;
unsigned int siz;
if (wpa_s->last_scan_res_size == 0)
siz = 32;
else
siz = wpa_s->last_scan_res_size * 2;
n = os_realloc_array(wpa_s->last_scan_res, siz,
sizeof(struct wpa_bss *));
if (n == NULL)
return;
wpa_s->last_scan_res = n;
wpa_s->last_scan_res_size = siz;
}
if (wpa_s->last_scan_res)
wpa_s->last_scan_res[wpa_s->last_scan_res_used++] = bss;
}
/**
* wpa_bss_update_end - End a BSS table update from scan results
* @wpa_s: Pointer to wpa_supplicant data
* @info: Information about scan parameters
* @new_scan: Whether this update round was based on a new scan
*
* This function is called at the end of each BSS table update round for new
* scan results. The start of the update was indicated with a call to
* wpa_bss_update_start().
*/
void wpa_bss_update_end(struct wpa_supplicant *wpa_s)
{
os_get_reltime(&wpa_s->last_scan);
}
/**
* wpa_bss_init - Initialize BSS table
* @wpa_s: Pointer to wpa_supplicant data
* Returns: 0 on success, -1 on failure
*
* This prepares BSS table lists and timer for periodic updates. The BSS table
* is deinitialized with wpa_bss_deinit() once not needed anymore.
*/
int wpa_bss_init(struct wpa_supplicant *wpa_s)
{
dl_list_init(&wpa_s->bss);
dl_list_init(&wpa_s->bss_id);
return 0;
}
/**
* wpa_bss_flush - Flush all unused BSS entries
* @wpa_s: Pointer to wpa_supplicant data
*/
void wpa_bss_flush(struct wpa_supplicant *wpa_s)
{
struct wpa_bss *bss, *n;
if (wpa_s->bss.next == NULL)
return; /* BSS table not yet initialized */
dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
if (wpa_bss_in_use(wpa_s, bss))
continue;
wpa_bss_remove(wpa_s, bss, __func__);
}
}
/**
* wpa_bss_deinit - Deinitialize BSS table
* @wpa_s: Pointer to wpa_supplicant data
*/
void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
{
wpa_bss_flush(wpa_s);
}
/**
* wpa_bss_get_bssid - Fetch a BSS table entry based on BSSID
* @wpa_s: Pointer to wpa_supplicant data
* @bssid: BSSID
* Returns: Pointer to the BSS entry or %NULL if not found
*/
struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
const u8 *bssid)
{
struct wpa_bss *bss;
dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
return bss;
}
return NULL;
}
/**
* wpa_bss_get_next_bss - Fetch a next BSS table entry from the list
* @wpa_s: Pointer to wpa_supplicant data
* @bss: BSS
* Returns: Pointer to the BSS entry or %NULL if not found
*/
struct wpa_bss * wpa_bss_get_next_bss(struct wpa_supplicant *wpa_s,
struct wpa_bss *prev_bss)
{
struct wpa_bss *bss;
if (!prev_bss)
return dl_list_first(&wpa_s->bss, struct wpa_bss, list);
dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
if (os_memcmp(bss->bssid, prev_bss->bssid, ETH_ALEN) == 0)
return dl_list_entry(bss->list.next, struct wpa_bss, list);
}
return NULL;
}
/**
* wpa_bss_get_ie - Fetch a specified information element from a BSS entry
* @bss: BSS table entry
* @ie: Information element identitifier (WLAN_EID_*)
* Returns: Pointer to the information element (id field) or %NULL if not found
*
* This function returns the first matching information element in the BSS
* entry.
*/
const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie)
{
return get_ie((const u8 *) (bss + 1), bss->ie_len, ie);
}
/**
* wpa_bss_get_vendor_ie - Fetch a vendor information element from a BSS entry
* @bss: BSS table entry
* @vendor_type: Vendor type (four octets starting the IE payload)
* Returns: Pointer to the information element (id field) or %NULL if not found
*
* This function returns the first matching information element in the BSS
* entry.
*/
const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type)
{
const u8 *ies;
const struct element *elem;
ies = wpa_bss_ie_ptr(bss);
for_each_element_id(elem, WLAN_EID_VENDOR_SPECIFIC, ies, bss->ie_len) {
if (elem->datalen >= 4 &&
vendor_type == WPA_GET_BE32(elem->data))
return &elem->id;
}
return NULL;
}
int wpa_bss_ext_capab(const struct wpa_bss *bss, unsigned int capab)
{
return ieee802_11_ext_capab(wpa_bss_get_ie(bss, WLAN_EID_EXT_CAPAB),
capab);
}
Details ![]()
Show: from Types: Columns: ![]( "Show Project Names")
![]( "Show Locations")
![]( "Show Referring Symbols")
![]( "Show Scope")
This file uses the notable symbols shown below. Click anywhere in the file to view more details.