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Commit | Line | Data |
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6fc6879b JM |
1 | /* |
2 | * WPA Supplicant - Scanning | |
9ba9fa07 | 3 | * Copyright (c) 2003-2010, Jouni Malinen <j@w1.fi> |
6fc6879b JM |
4 | * |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License version 2 as | |
7 | * published by the Free Software Foundation. | |
8 | * | |
9 | * Alternatively, this software may be distributed under the terms of BSD | |
10 | * license. | |
11 | * | |
12 | * See README and COPYING for more details. | |
13 | */ | |
14 | ||
9ba9fa07 | 15 | #include "utils/includes.h" |
6fc6879b | 16 | |
9ba9fa07 JM |
17 | #include "utils/common.h" |
18 | #include "utils/eloop.h" | |
19 | #include "common/ieee802_11_defs.h" | |
6fc6879b JM |
20 | #include "config.h" |
21 | #include "wpa_supplicant_i.h" | |
2d5b792d | 22 | #include "driver_i.h" |
6fc6879b | 23 | #include "mlme.h" |
b01c18a8 | 24 | #include "wps_supplicant.h" |
8bac466b | 25 | #include "notify.h" |
9ba9fa07 JM |
26 | #include "bss.h" |
27 | #include "scan.h" | |
6fc6879b JM |
28 | |
29 | ||
30 | static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s) | |
31 | { | |
32 | struct wpa_ssid *ssid; | |
33 | union wpa_event_data data; | |
34 | ||
35 | ssid = wpa_supplicant_get_ssid(wpa_s); | |
36 | if (ssid == NULL) | |
37 | return; | |
38 | ||
8bac466b | 39 | if (wpa_s->current_ssid == NULL) { |
6fc6879b | 40 | wpa_s->current_ssid = ssid; |
8bac466b JM |
41 | if (wpa_s->current_ssid != NULL) |
42 | wpas_notify_network_changed(wpa_s); | |
43 | } | |
6fc6879b JM |
44 | wpa_supplicant_initiate_eapol(wpa_s); |
45 | wpa_printf(MSG_DEBUG, "Already associated with a configured network - " | |
46 | "generating associated event"); | |
47 | os_memset(&data, 0, sizeof(data)); | |
48 | wpa_supplicant_event(wpa_s, EVENT_ASSOC, &data); | |
49 | } | |
50 | ||
51 | ||
ad08c363 | 52 | #ifdef CONFIG_WPS |
f90c86d4 JM |
53 | static int wpas_wps_in_use(struct wpa_config *conf, |
54 | enum wps_request_type *req_type) | |
ad08c363 JM |
55 | { |
56 | struct wpa_ssid *ssid; | |
57 | int wps = 0; | |
ad08c363 JM |
58 | |
59 | for (ssid = conf->ssid; ssid; ssid = ssid->next) { | |
60 | if (!(ssid->key_mgmt & WPA_KEY_MGMT_WPS)) | |
61 | continue; | |
62 | ||
63 | wps = 1; | |
b01c18a8 | 64 | *req_type = wpas_wps_get_req_type(ssid); |
ad08c363 JM |
65 | if (!ssid->eap.phase1) |
66 | continue; | |
67 | ||
ad08c363 JM |
68 | if (os_strstr(ssid->eap.phase1, "pbc=1")) |
69 | return 2; | |
70 | } | |
71 | ||
72 | return wps; | |
73 | } | |
74 | #endif /* CONFIG_WPS */ | |
75 | ||
e76baaac | 76 | |
4f34d51a | 77 | int wpa_supplicant_enabled_networks(struct wpa_config *conf) |
e76baaac JM |
78 | { |
79 | struct wpa_ssid *ssid = conf->ssid; | |
80 | while (ssid) { | |
81 | if (!ssid->disabled) | |
82 | return 1; | |
83 | ssid = ssid->next; | |
84 | } | |
85 | return 0; | |
86 | } | |
87 | ||
88 | ||
89 | static void wpa_supplicant_assoc_try(struct wpa_supplicant *wpa_s, | |
90 | struct wpa_ssid *ssid) | |
91 | { | |
92 | while (ssid) { | |
93 | if (!ssid->disabled) | |
94 | break; | |
95 | ssid = ssid->next; | |
96 | } | |
97 | ||
98 | /* ap_scan=2 mode - try to associate with each SSID. */ | |
99 | if (ssid == NULL) { | |
100 | wpa_printf(MSG_DEBUG, "wpa_supplicant_scan: Reached " | |
101 | "end of scan list - go back to beginning"); | |
ba2a573c | 102 | wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN; |
e76baaac JM |
103 | wpa_supplicant_req_scan(wpa_s, 0, 0); |
104 | return; | |
105 | } | |
106 | if (ssid->next) { | |
107 | /* Continue from the next SSID on the next attempt. */ | |
108 | wpa_s->prev_scan_ssid = ssid; | |
109 | } else { | |
110 | /* Start from the beginning of the SSID list. */ | |
ba2a573c | 111 | wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN; |
e76baaac JM |
112 | } |
113 | wpa_supplicant_associate(wpa_s, NULL, ssid); | |
114 | } | |
115 | ||
116 | ||
d3a98225 JM |
117 | static int int_array_len(const int *a) |
118 | { | |
119 | int i; | |
120 | for (i = 0; a && a[i]; i++) | |
121 | ; | |
122 | return i; | |
123 | } | |
124 | ||
125 | ||
126 | static void int_array_concat(int **res, const int *a) | |
127 | { | |
128 | int reslen, alen, i; | |
129 | int *n; | |
130 | ||
131 | reslen = int_array_len(*res); | |
132 | alen = int_array_len(a); | |
133 | ||
134 | n = os_realloc(*res, (reslen + alen + 1) * sizeof(int)); | |
135 | if (n == NULL) { | |
136 | os_free(*res); | |
137 | *res = NULL; | |
e6c0ebff | 138 | return; |
d3a98225 JM |
139 | } |
140 | for (i = 0; i <= alen; i++) | |
141 | n[reslen + i] = a[i]; | |
142 | *res = n; | |
143 | } | |
144 | ||
145 | ||
146 | static int freq_cmp(const void *a, const void *b) | |
147 | { | |
148 | int _a = *(int *) a; | |
149 | int _b = *(int *) b; | |
150 | ||
151 | if (_a == 0) | |
152 | return 1; | |
153 | if (_b == 0) | |
154 | return -1; | |
155 | return _a - _b; | |
156 | } | |
157 | ||
158 | ||
159 | static void int_array_sort_unique(int *a) | |
160 | { | |
161 | int alen; | |
162 | int i, j; | |
163 | ||
164 | if (a == NULL) | |
165 | return; | |
166 | ||
167 | alen = int_array_len(a); | |
168 | qsort(a, alen, sizeof(int), freq_cmp); | |
169 | ||
170 | i = 0; | |
171 | j = 1; | |
172 | while (a[i] && a[j]) { | |
173 | if (a[i] == a[j]) { | |
174 | j++; | |
175 | continue; | |
176 | } | |
177 | a[++i] = a[j++]; | |
178 | } | |
179 | if (a[i]) | |
180 | i++; | |
181 | a[i] = 0; | |
182 | } | |
183 | ||
184 | ||
60b94c98 JM |
185 | int wpa_supplicant_trigger_scan(struct wpa_supplicant *wpa_s, |
186 | struct wpa_driver_scan_params *params) | |
187 | { | |
188 | int ret; | |
189 | ||
190 | wpa_supplicant_notify_scanning(wpa_s, 1); | |
191 | ||
d009a9da JM |
192 | if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME) |
193 | ret = ieee80211_sta_req_scan(wpa_s, params); | |
194 | else | |
60b94c98 | 195 | ret = wpa_drv_scan(wpa_s, params); |
60b94c98 JM |
196 | |
197 | if (ret) { | |
198 | wpa_supplicant_notify_scanning(wpa_s, 0); | |
199 | wpas_notify_scan_done(wpa_s, 0); | |
200 | } else | |
201 | wpa_s->scan_runs++; | |
202 | ||
203 | return ret; | |
204 | } | |
205 | ||
206 | ||
6fc6879b JM |
207 | static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx) |
208 | { | |
209 | struct wpa_supplicant *wpa_s = eloop_ctx; | |
210 | struct wpa_ssid *ssid; | |
e76baaac | 211 | int scan_req = 0, ret; |
ad08c363 | 212 | struct wpabuf *wps_ie = NULL; |
ad08c363 | 213 | int wps = 0; |
b01c18a8 | 214 | #ifdef CONFIG_WPS |
f90c86d4 | 215 | enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO; |
b01c18a8 | 216 | #endif /* CONFIG_WPS */ |
e76baaac JM |
217 | struct wpa_driver_scan_params params; |
218 | size_t max_ssids; | |
207ef3fb | 219 | enum wpa_states prev_state; |
6fc6879b | 220 | |
3180d7a2 SO |
221 | if (wpa_s->disconnected && !wpa_s->scan_req) { |
222 | wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED); | |
6fc6879b | 223 | return; |
3180d7a2 | 224 | } |
6fc6879b | 225 | |
e76baaac JM |
226 | if (!wpa_supplicant_enabled_networks(wpa_s->conf) && |
227 | !wpa_s->scan_req) { | |
6fc6879b JM |
228 | wpa_printf(MSG_DEBUG, "No enabled networks - do not scan"); |
229 | wpa_supplicant_set_state(wpa_s, WPA_INACTIVE); | |
230 | return; | |
231 | } | |
6fc6879b | 232 | |
c2a04078 JM |
233 | if (wpa_s->conf->ap_scan != 0 && |
234 | (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) { | |
e519314e JW |
235 | wpa_printf(MSG_DEBUG, "Using wired authentication - " |
236 | "overriding ap_scan configuration"); | |
6fc6879b | 237 | wpa_s->conf->ap_scan = 0; |
8bac466b | 238 | wpas_notify_ap_scan_changed(wpa_s); |
6fc6879b JM |
239 | } |
240 | ||
241 | if (wpa_s->conf->ap_scan == 0) { | |
242 | wpa_supplicant_gen_assoc_event(wpa_s); | |
243 | return; | |
244 | } | |
245 | ||
c2a04078 JM |
246 | if ((wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME) || |
247 | wpa_s->conf->ap_scan == 2) | |
e76baaac JM |
248 | max_ssids = 1; |
249 | else { | |
250 | max_ssids = wpa_s->max_scan_ssids; | |
251 | if (max_ssids > WPAS_MAX_SCAN_SSIDS) | |
252 | max_ssids = WPAS_MAX_SCAN_SSIDS; | |
253 | } | |
254 | ||
255 | #ifdef CONFIG_WPS | |
256 | wps = wpas_wps_in_use(wpa_s->conf, &req_type); | |
257 | #endif /* CONFIG_WPS */ | |
258 | ||
259 | if (wpa_s->scan_res_tried == 0 && wpa_s->conf->ap_scan == 1 && | |
c2a04078 JM |
260 | !(wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME) && |
261 | wps != 2) { | |
e76baaac JM |
262 | wpa_s->scan_res_tried++; |
263 | wpa_printf(MSG_DEBUG, "Trying to get current scan results " | |
264 | "first without requesting a new scan to speed up " | |
265 | "initial association"); | |
266 | wpa_supplicant_event(wpa_s, EVENT_SCAN_RESULTS, NULL); | |
267 | return; | |
268 | } | |
269 | ||
270 | scan_req = wpa_s->scan_req; | |
271 | wpa_s->scan_req = 0; | |
272 | ||
273 | os_memset(¶ms, 0, sizeof(params)); | |
274 | ||
207ef3fb | 275 | prev_state = wpa_s->wpa_state; |
6fc6879b JM |
276 | if (wpa_s->wpa_state == WPA_DISCONNECTED || |
277 | wpa_s->wpa_state == WPA_INACTIVE) | |
278 | wpa_supplicant_set_state(wpa_s, WPA_SCANNING); | |
279 | ||
e76baaac | 280 | /* Find the starting point from which to continue scanning */ |
6fc6879b | 281 | ssid = wpa_s->conf->ssid; |
ba2a573c | 282 | if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) { |
6fc6879b JM |
283 | while (ssid) { |
284 | if (ssid == wpa_s->prev_scan_ssid) { | |
285 | ssid = ssid->next; | |
286 | break; | |
287 | } | |
288 | ssid = ssid->next; | |
289 | } | |
290 | } | |
6fc6879b JM |
291 | |
292 | if (scan_req != 2 && wpa_s->conf->ap_scan == 2) { | |
e76baaac JM |
293 | wpa_supplicant_assoc_try(wpa_s, ssid); |
294 | return; | |
295 | } else if (wpa_s->conf->ap_scan == 2) { | |
6fc6879b | 296 | /* |
ba2a573c JM |
297 | * User-initiated scan request in ap_scan == 2; scan with |
298 | * wildcard SSID. | |
6fc6879b | 299 | */ |
e76baaac JM |
300 | ssid = NULL; |
301 | } else { | |
5be45e2e | 302 | struct wpa_ssid *start = ssid, *tssid; |
d3a98225 | 303 | int freqs_set = 0; |
e76baaac JM |
304 | if (ssid == NULL && max_ssids > 1) |
305 | ssid = wpa_s->conf->ssid; | |
306 | while (ssid) { | |
307 | if (!ssid->disabled && ssid->scan_ssid) { | |
308 | wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID", | |
309 | ssid->ssid, ssid->ssid_len); | |
310 | params.ssids[params.num_ssids].ssid = | |
311 | ssid->ssid; | |
312 | params.ssids[params.num_ssids].ssid_len = | |
313 | ssid->ssid_len; | |
314 | params.num_ssids++; | |
315 | if (params.num_ssids + 1 >= max_ssids) | |
316 | break; | |
317 | } | |
318 | ssid = ssid->next; | |
319 | if (ssid == start) | |
320 | break; | |
321 | if (ssid == NULL && max_ssids > 1 && | |
322 | start != wpa_s->conf->ssid) | |
323 | ssid = wpa_s->conf->ssid; | |
6fc6879b | 324 | } |
d3a98225 | 325 | |
5be45e2e JM |
326 | for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) { |
327 | if (tssid->disabled) | |
d3a98225 | 328 | continue; |
5be45e2e | 329 | if ((params.freqs || !freqs_set) && tssid->scan_freq) { |
d3a98225 | 330 | int_array_concat(¶ms.freqs, |
5be45e2e | 331 | tssid->scan_freq); |
d3a98225 JM |
332 | } else { |
333 | os_free(params.freqs); | |
334 | params.freqs = NULL; | |
335 | } | |
336 | freqs_set = 1; | |
337 | } | |
338 | int_array_sort_unique(params.freqs); | |
6fc6879b JM |
339 | } |
340 | ||
6fc6879b | 341 | if (ssid) { |
6fc6879b | 342 | wpa_s->prev_scan_ssid = ssid; |
e76baaac | 343 | if (max_ssids > 1) { |
ba2a573c | 344 | wpa_printf(MSG_DEBUG, "Include wildcard SSID in the " |
e76baaac | 345 | "scan request"); |
ba2a573c | 346 | params.num_ssids++; |
e76baaac JM |
347 | } |
348 | wpa_printf(MSG_DEBUG, "Starting AP scan for specific SSID(s)"); | |
349 | } else { | |
ba2a573c | 350 | wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN; |
e76baaac | 351 | params.num_ssids++; |
ba2a573c | 352 | wpa_printf(MSG_DEBUG, "Starting AP scan for wildcard SSID"); |
6fc6879b JM |
353 | } |
354 | ||
ad08c363 JM |
355 | #ifdef CONFIG_WPS |
356 | if (wps) { | |
c0d041d9 | 357 | wps_ie = wps_build_probe_req_ie(wps == 2, &wpa_s->wps->dev, |
79da74a2 | 358 | wpa_s->wps->uuid, req_type); |
ad08c363 | 359 | if (wps_ie) { |
e76baaac JM |
360 | params.extra_ies = wpabuf_head(wps_ie); |
361 | params.extra_ies_len = wpabuf_len(wps_ie); | |
ad08c363 JM |
362 | } |
363 | } | |
364 | #endif /* CONFIG_WPS */ | |
365 | ||
60b94c98 | 366 | ret = wpa_supplicant_trigger_scan(wpa_s, ¶ms); |
6fc6879b | 367 | |
ad08c363 | 368 | wpabuf_free(wps_ie); |
d3a98225 | 369 | os_free(params.freqs); |
ad08c363 | 370 | |
6fc6879b JM |
371 | if (ret) { |
372 | wpa_printf(MSG_WARNING, "Failed to initiate AP scan."); | |
207ef3fb JM |
373 | if (prev_state != wpa_s->wpa_state) |
374 | wpa_supplicant_set_state(wpa_s, prev_state); | |
6fc6879b | 375 | wpa_supplicant_req_scan(wpa_s, 10, 0); |
a6099152 JM |
376 | } else |
377 | wpa_s->scan_runs++; | |
6fc6879b JM |
378 | } |
379 | ||
380 | ||
381 | /** | |
382 | * wpa_supplicant_req_scan - Schedule a scan for neighboring access points | |
383 | * @wpa_s: Pointer to wpa_supplicant data | |
384 | * @sec: Number of seconds after which to scan | |
385 | * @usec: Number of microseconds after which to scan | |
386 | * | |
387 | * This function is used to schedule a scan for neighboring access points after | |
388 | * the specified time. | |
389 | */ | |
390 | void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec) | |
391 | { | |
7e148849 DW |
392 | /* If there's at least one network that should be specifically scanned |
393 | * then don't cancel the scan and reschedule. Some drivers do | |
394 | * background scanning which generates frequent scan results, and that | |
395 | * causes the specific SSID scan to get continually pushed back and | |
396 | * never happen, which causes hidden APs to never get probe-scanned. | |
397 | */ | |
398 | if (eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL) && | |
399 | wpa_s->conf->ap_scan == 1) { | |
400 | struct wpa_ssid *ssid = wpa_s->conf->ssid; | |
401 | ||
402 | while (ssid) { | |
403 | if (!ssid->disabled && ssid->scan_ssid) | |
404 | break; | |
405 | ssid = ssid->next; | |
406 | } | |
407 | if (ssid) { | |
408 | wpa_msg(wpa_s, MSG_DEBUG, "Not rescheduling scan to " | |
409 | "ensure that specific SSID scans occur"); | |
410 | return; | |
411 | } | |
412 | } | |
413 | ||
6fc6879b JM |
414 | wpa_msg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec", |
415 | sec, usec); | |
416 | eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL); | |
417 | eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL); | |
418 | } | |
419 | ||
420 | ||
421 | /** | |
422 | * wpa_supplicant_cancel_scan - Cancel a scheduled scan request | |
423 | * @wpa_s: Pointer to wpa_supplicant data | |
424 | * | |
425 | * This function is used to cancel a scan request scheduled with | |
426 | * wpa_supplicant_req_scan(). | |
427 | */ | |
428 | void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s) | |
429 | { | |
430 | wpa_msg(wpa_s, MSG_DEBUG, "Cancelling scan request"); | |
431 | eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL); | |
432 | } | |
cb8564b1 DW |
433 | |
434 | ||
435 | void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s, | |
436 | int scanning) | |
437 | { | |
438 | if (wpa_s->scanning != scanning) { | |
439 | wpa_s->scanning = scanning; | |
8bac466b | 440 | wpas_notify_scanning(wpa_s); |
cb8564b1 DW |
441 | } |
442 | } | |
443 | ||
9ba9fa07 JM |
444 | |
445 | static int wpa_scan_get_max_rate(const struct wpa_scan_res *res) | |
446 | { | |
447 | int rate = 0; | |
448 | const u8 *ie; | |
449 | int i; | |
450 | ||
451 | ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES); | |
452 | for (i = 0; ie && i < ie[1]; i++) { | |
453 | if ((ie[i + 2] & 0x7f) > rate) | |
454 | rate = ie[i + 2] & 0x7f; | |
455 | } | |
456 | ||
457 | ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES); | |
458 | for (i = 0; ie && i < ie[1]; i++) { | |
459 | if ((ie[i + 2] & 0x7f) > rate) | |
460 | rate = ie[i + 2] & 0x7f; | |
461 | } | |
462 | ||
463 | return rate; | |
464 | } | |
465 | ||
466 | ||
d1f9c410 JM |
467 | const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie) |
468 | { | |
469 | const u8 *end, *pos; | |
470 | ||
471 | pos = (const u8 *) (res + 1); | |
472 | end = pos + res->ie_len; | |
473 | ||
474 | while (pos + 1 < end) { | |
475 | if (pos + 2 + pos[1] > end) | |
476 | break; | |
477 | if (pos[0] == ie) | |
478 | return pos; | |
479 | pos += 2 + pos[1]; | |
480 | } | |
481 | ||
482 | return NULL; | |
483 | } | |
484 | ||
485 | ||
9ba9fa07 JM |
486 | const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res, |
487 | u32 vendor_type) | |
488 | { | |
489 | const u8 *end, *pos; | |
490 | ||
491 | pos = (const u8 *) (res + 1); | |
492 | end = pos + res->ie_len; | |
493 | ||
494 | while (pos + 1 < end) { | |
495 | if (pos + 2 + pos[1] > end) | |
496 | break; | |
497 | if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && | |
498 | vendor_type == WPA_GET_BE32(&pos[2])) | |
499 | return pos; | |
500 | pos += 2 + pos[1]; | |
501 | } | |
502 | ||
503 | return NULL; | |
504 | } | |
505 | ||
506 | ||
507 | struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res, | |
508 | u32 vendor_type) | |
509 | { | |
510 | struct wpabuf *buf; | |
511 | const u8 *end, *pos; | |
512 | ||
513 | buf = wpabuf_alloc(res->ie_len); | |
514 | if (buf == NULL) | |
515 | return NULL; | |
516 | ||
517 | pos = (const u8 *) (res + 1); | |
518 | end = pos + res->ie_len; | |
519 | ||
520 | while (pos + 1 < end) { | |
521 | if (pos + 2 + pos[1] > end) | |
522 | break; | |
523 | if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && | |
524 | vendor_type == WPA_GET_BE32(&pos[2])) | |
525 | wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4); | |
526 | pos += 2 + pos[1]; | |
527 | } | |
528 | ||
529 | if (wpabuf_len(buf) == 0) { | |
530 | wpabuf_free(buf); | |
531 | buf = NULL; | |
532 | } | |
533 | ||
534 | return buf; | |
535 | } | |
536 | ||
537 | ||
538 | /* Compare function for sorting scan results. Return >0 if @b is considered | |
539 | * better. */ | |
540 | static int wpa_scan_result_compar(const void *a, const void *b) | |
541 | { | |
542 | struct wpa_scan_res **_wa = (void *) a; | |
543 | struct wpa_scan_res **_wb = (void *) b; | |
544 | struct wpa_scan_res *wa = *_wa; | |
545 | struct wpa_scan_res *wb = *_wb; | |
546 | int wpa_a, wpa_b, maxrate_a, maxrate_b; | |
547 | ||
548 | /* WPA/WPA2 support preferred */ | |
549 | wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL || | |
550 | wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL; | |
551 | wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL || | |
552 | wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL; | |
553 | ||
554 | if (wpa_b && !wpa_a) | |
555 | return 1; | |
556 | if (!wpa_b && wpa_a) | |
557 | return -1; | |
558 | ||
559 | /* privacy support preferred */ | |
560 | if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 && | |
561 | (wb->caps & IEEE80211_CAP_PRIVACY)) | |
562 | return 1; | |
563 | if ((wa->caps & IEEE80211_CAP_PRIVACY) && | |
564 | (wb->caps & IEEE80211_CAP_PRIVACY) == 0) | |
565 | return -1; | |
566 | ||
567 | /* best/max rate preferred if signal level close enough XXX */ | |
568 | if ((wa->level && wb->level && abs(wb->level - wa->level) < 5) || | |
569 | (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) { | |
570 | maxrate_a = wpa_scan_get_max_rate(wa); | |
571 | maxrate_b = wpa_scan_get_max_rate(wb); | |
572 | if (maxrate_a != maxrate_b) | |
573 | return maxrate_b - maxrate_a; | |
574 | } | |
575 | ||
576 | /* use freq for channel preference */ | |
577 | ||
578 | /* all things being equal, use signal level; if signal levels are | |
579 | * identical, use quality values since some drivers may only report | |
580 | * that value and leave the signal level zero */ | |
581 | if (wb->level == wa->level) | |
582 | return wb->qual - wa->qual; | |
583 | return wb->level - wa->level; | |
584 | } | |
585 | ||
586 | ||
587 | /** | |
588 | * wpa_supplicant_get_scan_results - Get scan results | |
589 | * @wpa_s: Pointer to wpa_supplicant data | |
590 | * @info: Information about what was scanned or %NULL if not available | |
591 | * @new_scan: Whether a new scan was performed | |
592 | * Returns: Scan results, %NULL on failure | |
593 | * | |
594 | * This function request the current scan results from the driver and updates | |
595 | * the local BSS list wpa_s->bss. The caller is responsible for freeing the | |
596 | * results with wpa_scan_results_free(). | |
597 | */ | |
598 | struct wpa_scan_results * | |
599 | wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s, | |
600 | struct scan_info *info, int new_scan) | |
601 | { | |
602 | struct wpa_scan_results *scan_res; | |
603 | size_t i; | |
604 | ||
605 | if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME) | |
606 | scan_res = ieee80211_sta_get_scan_results(wpa_s); | |
607 | else | |
608 | scan_res = wpa_drv_get_scan_results2(wpa_s); | |
609 | if (scan_res == NULL) { | |
610 | wpa_printf(MSG_DEBUG, "Failed to get scan results"); | |
611 | return NULL; | |
612 | } | |
613 | ||
614 | qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *), | |
615 | wpa_scan_result_compar); | |
616 | ||
617 | wpa_bss_update_start(wpa_s); | |
618 | for (i = 0; i < scan_res->num; i++) | |
619 | wpa_bss_update_scan_res(wpa_s, scan_res->res[i]); | |
620 | wpa_bss_update_end(wpa_s, info, new_scan); | |
621 | ||
622 | return scan_res; | |
623 | } | |
624 | ||
625 | ||
626 | int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s) | |
627 | { | |
628 | struct wpa_scan_results *scan_res; | |
629 | scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0); | |
630 | if (scan_res == NULL) | |
631 | return -1; | |
632 | wpa_scan_results_free(scan_res); | |
633 | ||
634 | return 0; | |
635 | } | |
d1f9c410 JM |
636 | |
637 | ||
638 | void wpa_scan_results_free(struct wpa_scan_results *res) | |
639 | { | |
640 | size_t i; | |
641 | ||
642 | if (res == NULL) | |
643 | return; | |
644 | ||
645 | for (i = 0; i < res->num; i++) | |
646 | os_free(res->res[i]); | |
647 | os_free(res->res); | |
648 | os_free(res); | |
649 | } |