]>
Commit | Line | Data |
---|---|---|
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 | ||
3812464c JM |
207 | static struct wpa_driver_scan_filter * |
208 | wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids) | |
209 | { | |
210 | struct wpa_driver_scan_filter *ssids; | |
211 | struct wpa_ssid *ssid; | |
212 | size_t count; | |
213 | ||
214 | *num_ssids = 0; | |
215 | if (!conf->filter_ssids) | |
216 | return NULL; | |
217 | ||
218 | for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) { | |
219 | if (ssid->ssid && ssid->ssid_len) | |
220 | count++; | |
221 | } | |
222 | if (count == 0) | |
223 | return NULL; | |
224 | ssids = os_zalloc(count * sizeof(struct wpa_driver_scan_filter)); | |
225 | if (ssids == NULL) | |
226 | return NULL; | |
227 | ||
228 | for (ssid = conf->ssid; ssid; ssid = ssid->next) { | |
229 | if (!ssid->ssid || !ssid->ssid_len) | |
230 | continue; | |
231 | os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len); | |
232 | ssids[*num_ssids].ssid_len = ssid->ssid_len; | |
233 | (*num_ssids)++; | |
234 | } | |
235 | ||
236 | return ssids; | |
237 | } | |
238 | ||
239 | ||
6fc6879b JM |
240 | static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx) |
241 | { | |
242 | struct wpa_supplicant *wpa_s = eloop_ctx; | |
243 | struct wpa_ssid *ssid; | |
e76baaac | 244 | int scan_req = 0, ret; |
ad08c363 | 245 | struct wpabuf *wps_ie = NULL; |
ad08c363 | 246 | int wps = 0; |
b01c18a8 | 247 | #ifdef CONFIG_WPS |
f90c86d4 | 248 | enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO; |
b01c18a8 | 249 | #endif /* CONFIG_WPS */ |
e76baaac JM |
250 | struct wpa_driver_scan_params params; |
251 | size_t max_ssids; | |
207ef3fb | 252 | enum wpa_states prev_state; |
6fc6879b | 253 | |
3180d7a2 SO |
254 | if (wpa_s->disconnected && !wpa_s->scan_req) { |
255 | wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED); | |
6fc6879b | 256 | return; |
3180d7a2 | 257 | } |
6fc6879b | 258 | |
e76baaac JM |
259 | if (!wpa_supplicant_enabled_networks(wpa_s->conf) && |
260 | !wpa_s->scan_req) { | |
6fc6879b JM |
261 | wpa_printf(MSG_DEBUG, "No enabled networks - do not scan"); |
262 | wpa_supplicant_set_state(wpa_s, WPA_INACTIVE); | |
263 | return; | |
264 | } | |
6fc6879b | 265 | |
c2a04078 JM |
266 | if (wpa_s->conf->ap_scan != 0 && |
267 | (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) { | |
e519314e JW |
268 | wpa_printf(MSG_DEBUG, "Using wired authentication - " |
269 | "overriding ap_scan configuration"); | |
6fc6879b | 270 | wpa_s->conf->ap_scan = 0; |
8bac466b | 271 | wpas_notify_ap_scan_changed(wpa_s); |
6fc6879b JM |
272 | } |
273 | ||
274 | if (wpa_s->conf->ap_scan == 0) { | |
275 | wpa_supplicant_gen_assoc_event(wpa_s); | |
276 | return; | |
277 | } | |
278 | ||
c2a04078 JM |
279 | if ((wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME) || |
280 | wpa_s->conf->ap_scan == 2) | |
e76baaac JM |
281 | max_ssids = 1; |
282 | else { | |
283 | max_ssids = wpa_s->max_scan_ssids; | |
284 | if (max_ssids > WPAS_MAX_SCAN_SSIDS) | |
285 | max_ssids = WPAS_MAX_SCAN_SSIDS; | |
286 | } | |
287 | ||
288 | #ifdef CONFIG_WPS | |
289 | wps = wpas_wps_in_use(wpa_s->conf, &req_type); | |
290 | #endif /* CONFIG_WPS */ | |
291 | ||
292 | if (wpa_s->scan_res_tried == 0 && wpa_s->conf->ap_scan == 1 && | |
c2a04078 | 293 | !(wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME) && |
3812464c | 294 | wps != 2 && !wpa_s->conf->filter_ssids) { |
e76baaac JM |
295 | wpa_s->scan_res_tried++; |
296 | wpa_printf(MSG_DEBUG, "Trying to get current scan results " | |
297 | "first without requesting a new scan to speed up " | |
298 | "initial association"); | |
299 | wpa_supplicant_event(wpa_s, EVENT_SCAN_RESULTS, NULL); | |
300 | return; | |
301 | } | |
302 | ||
303 | scan_req = wpa_s->scan_req; | |
304 | wpa_s->scan_req = 0; | |
305 | ||
306 | os_memset(¶ms, 0, sizeof(params)); | |
307 | ||
207ef3fb | 308 | prev_state = wpa_s->wpa_state; |
6fc6879b JM |
309 | if (wpa_s->wpa_state == WPA_DISCONNECTED || |
310 | wpa_s->wpa_state == WPA_INACTIVE) | |
311 | wpa_supplicant_set_state(wpa_s, WPA_SCANNING); | |
312 | ||
e76baaac | 313 | /* Find the starting point from which to continue scanning */ |
6fc6879b | 314 | ssid = wpa_s->conf->ssid; |
ba2a573c | 315 | if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) { |
6fc6879b JM |
316 | while (ssid) { |
317 | if (ssid == wpa_s->prev_scan_ssid) { | |
318 | ssid = ssid->next; | |
319 | break; | |
320 | } | |
321 | ssid = ssid->next; | |
322 | } | |
323 | } | |
6fc6879b JM |
324 | |
325 | if (scan_req != 2 && wpa_s->conf->ap_scan == 2) { | |
e76baaac JM |
326 | wpa_supplicant_assoc_try(wpa_s, ssid); |
327 | return; | |
328 | } else if (wpa_s->conf->ap_scan == 2) { | |
6fc6879b | 329 | /* |
ba2a573c JM |
330 | * User-initiated scan request in ap_scan == 2; scan with |
331 | * wildcard SSID. | |
6fc6879b | 332 | */ |
e76baaac JM |
333 | ssid = NULL; |
334 | } else { | |
5be45e2e | 335 | struct wpa_ssid *start = ssid, *tssid; |
d3a98225 | 336 | int freqs_set = 0; |
e76baaac JM |
337 | if (ssid == NULL && max_ssids > 1) |
338 | ssid = wpa_s->conf->ssid; | |
339 | while (ssid) { | |
340 | if (!ssid->disabled && ssid->scan_ssid) { | |
341 | wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID", | |
342 | ssid->ssid, ssid->ssid_len); | |
343 | params.ssids[params.num_ssids].ssid = | |
344 | ssid->ssid; | |
345 | params.ssids[params.num_ssids].ssid_len = | |
346 | ssid->ssid_len; | |
347 | params.num_ssids++; | |
348 | if (params.num_ssids + 1 >= max_ssids) | |
349 | break; | |
350 | } | |
351 | ssid = ssid->next; | |
352 | if (ssid == start) | |
353 | break; | |
354 | if (ssid == NULL && max_ssids > 1 && | |
355 | start != wpa_s->conf->ssid) | |
356 | ssid = wpa_s->conf->ssid; | |
6fc6879b | 357 | } |
d3a98225 | 358 | |
5be45e2e JM |
359 | for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) { |
360 | if (tssid->disabled) | |
d3a98225 | 361 | continue; |
5be45e2e | 362 | if ((params.freqs || !freqs_set) && tssid->scan_freq) { |
d3a98225 | 363 | int_array_concat(¶ms.freqs, |
5be45e2e | 364 | tssid->scan_freq); |
d3a98225 JM |
365 | } else { |
366 | os_free(params.freqs); | |
367 | params.freqs = NULL; | |
368 | } | |
369 | freqs_set = 1; | |
370 | } | |
371 | int_array_sort_unique(params.freqs); | |
6fc6879b JM |
372 | } |
373 | ||
6fc6879b | 374 | if (ssid) { |
6fc6879b | 375 | wpa_s->prev_scan_ssid = ssid; |
e76baaac | 376 | if (max_ssids > 1) { |
ba2a573c | 377 | wpa_printf(MSG_DEBUG, "Include wildcard SSID in the " |
e76baaac | 378 | "scan request"); |
ba2a573c | 379 | params.num_ssids++; |
e76baaac JM |
380 | } |
381 | wpa_printf(MSG_DEBUG, "Starting AP scan for specific SSID(s)"); | |
382 | } else { | |
ba2a573c | 383 | wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN; |
e76baaac | 384 | params.num_ssids++; |
ba2a573c | 385 | wpa_printf(MSG_DEBUG, "Starting AP scan for wildcard SSID"); |
6fc6879b JM |
386 | } |
387 | ||
ad08c363 | 388 | #ifdef CONFIG_WPS |
17a4734d JM |
389 | if (params.freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) { |
390 | /* | |
391 | * Optimize post-provisioning scan based on channel used | |
392 | * during provisioning. | |
393 | */ | |
394 | wpa_printf(MSG_DEBUG, "WPS: Scan only frequency %u MHz that " | |
395 | "was used during provisioning", wpa_s->wps_freq); | |
396 | params.freqs = os_zalloc(2 * sizeof(int)); | |
397 | if (params.freqs) | |
398 | params.freqs[0] = wpa_s->wps_freq; | |
399 | wpa_s->after_wps--; | |
400 | } | |
401 | ||
ad08c363 | 402 | if (wps) { |
c0d041d9 | 403 | wps_ie = wps_build_probe_req_ie(wps == 2, &wpa_s->wps->dev, |
79da74a2 | 404 | wpa_s->wps->uuid, req_type); |
ad08c363 | 405 | if (wps_ie) { |
e76baaac JM |
406 | params.extra_ies = wpabuf_head(wps_ie); |
407 | params.extra_ies_len = wpabuf_len(wps_ie); | |
ad08c363 JM |
408 | } |
409 | } | |
410 | #endif /* CONFIG_WPS */ | |
411 | ||
3812464c JM |
412 | params.filter_ssids = wpa_supplicant_build_filter_ssids( |
413 | wpa_s->conf, ¶ms.num_filter_ssids); | |
414 | ||
60b94c98 | 415 | ret = wpa_supplicant_trigger_scan(wpa_s, ¶ms); |
6fc6879b | 416 | |
ad08c363 | 417 | wpabuf_free(wps_ie); |
d3a98225 | 418 | os_free(params.freqs); |
3812464c | 419 | os_free(params.filter_ssids); |
ad08c363 | 420 | |
6fc6879b JM |
421 | if (ret) { |
422 | wpa_printf(MSG_WARNING, "Failed to initiate AP scan."); | |
207ef3fb JM |
423 | if (prev_state != wpa_s->wpa_state) |
424 | wpa_supplicant_set_state(wpa_s, prev_state); | |
6fc6879b | 425 | wpa_supplicant_req_scan(wpa_s, 10, 0); |
a6099152 JM |
426 | } else |
427 | wpa_s->scan_runs++; | |
6fc6879b JM |
428 | } |
429 | ||
430 | ||
431 | /** | |
432 | * wpa_supplicant_req_scan - Schedule a scan for neighboring access points | |
433 | * @wpa_s: Pointer to wpa_supplicant data | |
434 | * @sec: Number of seconds after which to scan | |
435 | * @usec: Number of microseconds after which to scan | |
436 | * | |
437 | * This function is used to schedule a scan for neighboring access points after | |
438 | * the specified time. | |
439 | */ | |
440 | void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec) | |
441 | { | |
7e148849 DW |
442 | /* If there's at least one network that should be specifically scanned |
443 | * then don't cancel the scan and reschedule. Some drivers do | |
444 | * background scanning which generates frequent scan results, and that | |
445 | * causes the specific SSID scan to get continually pushed back and | |
446 | * never happen, which causes hidden APs to never get probe-scanned. | |
447 | */ | |
448 | if (eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL) && | |
449 | wpa_s->conf->ap_scan == 1) { | |
450 | struct wpa_ssid *ssid = wpa_s->conf->ssid; | |
451 | ||
452 | while (ssid) { | |
453 | if (!ssid->disabled && ssid->scan_ssid) | |
454 | break; | |
455 | ssid = ssid->next; | |
456 | } | |
457 | if (ssid) { | |
458 | wpa_msg(wpa_s, MSG_DEBUG, "Not rescheduling scan to " | |
459 | "ensure that specific SSID scans occur"); | |
460 | return; | |
461 | } | |
462 | } | |
463 | ||
6fc6879b JM |
464 | wpa_msg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec", |
465 | sec, usec); | |
466 | eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL); | |
467 | eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL); | |
468 | } | |
469 | ||
470 | ||
471 | /** | |
472 | * wpa_supplicant_cancel_scan - Cancel a scheduled scan request | |
473 | * @wpa_s: Pointer to wpa_supplicant data | |
474 | * | |
475 | * This function is used to cancel a scan request scheduled with | |
476 | * wpa_supplicant_req_scan(). | |
477 | */ | |
478 | void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s) | |
479 | { | |
480 | wpa_msg(wpa_s, MSG_DEBUG, "Cancelling scan request"); | |
481 | eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL); | |
482 | } | |
cb8564b1 DW |
483 | |
484 | ||
485 | void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s, | |
486 | int scanning) | |
487 | { | |
488 | if (wpa_s->scanning != scanning) { | |
489 | wpa_s->scanning = scanning; | |
8bac466b | 490 | wpas_notify_scanning(wpa_s); |
cb8564b1 DW |
491 | } |
492 | } | |
493 | ||
9ba9fa07 JM |
494 | |
495 | static int wpa_scan_get_max_rate(const struct wpa_scan_res *res) | |
496 | { | |
497 | int rate = 0; | |
498 | const u8 *ie; | |
499 | int i; | |
500 | ||
501 | ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES); | |
502 | for (i = 0; ie && i < ie[1]; i++) { | |
503 | if ((ie[i + 2] & 0x7f) > rate) | |
504 | rate = ie[i + 2] & 0x7f; | |
505 | } | |
506 | ||
507 | ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES); | |
508 | for (i = 0; ie && i < ie[1]; i++) { | |
509 | if ((ie[i + 2] & 0x7f) > rate) | |
510 | rate = ie[i + 2] & 0x7f; | |
511 | } | |
512 | ||
513 | return rate; | |
514 | } | |
515 | ||
516 | ||
d1f9c410 JM |
517 | const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie) |
518 | { | |
519 | const u8 *end, *pos; | |
520 | ||
521 | pos = (const u8 *) (res + 1); | |
522 | end = pos + res->ie_len; | |
523 | ||
524 | while (pos + 1 < end) { | |
525 | if (pos + 2 + pos[1] > end) | |
526 | break; | |
527 | if (pos[0] == ie) | |
528 | return pos; | |
529 | pos += 2 + pos[1]; | |
530 | } | |
531 | ||
532 | return NULL; | |
533 | } | |
534 | ||
535 | ||
9ba9fa07 JM |
536 | const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res, |
537 | u32 vendor_type) | |
538 | { | |
539 | const u8 *end, *pos; | |
540 | ||
541 | pos = (const u8 *) (res + 1); | |
542 | end = pos + res->ie_len; | |
543 | ||
544 | while (pos + 1 < end) { | |
545 | if (pos + 2 + pos[1] > end) | |
546 | break; | |
547 | if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && | |
548 | vendor_type == WPA_GET_BE32(&pos[2])) | |
549 | return pos; | |
550 | pos += 2 + pos[1]; | |
551 | } | |
552 | ||
553 | return NULL; | |
554 | } | |
555 | ||
556 | ||
557 | struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res, | |
558 | u32 vendor_type) | |
559 | { | |
560 | struct wpabuf *buf; | |
561 | const u8 *end, *pos; | |
562 | ||
563 | buf = wpabuf_alloc(res->ie_len); | |
564 | if (buf == NULL) | |
565 | return NULL; | |
566 | ||
567 | pos = (const u8 *) (res + 1); | |
568 | end = pos + res->ie_len; | |
569 | ||
570 | while (pos + 1 < end) { | |
571 | if (pos + 2 + pos[1] > end) | |
572 | break; | |
573 | if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 && | |
574 | vendor_type == WPA_GET_BE32(&pos[2])) | |
575 | wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4); | |
576 | pos += 2 + pos[1]; | |
577 | } | |
578 | ||
579 | if (wpabuf_len(buf) == 0) { | |
580 | wpabuf_free(buf); | |
581 | buf = NULL; | |
582 | } | |
583 | ||
584 | return buf; | |
585 | } | |
586 | ||
587 | ||
588 | /* Compare function for sorting scan results. Return >0 if @b is considered | |
589 | * better. */ | |
590 | static int wpa_scan_result_compar(const void *a, const void *b) | |
591 | { | |
592 | struct wpa_scan_res **_wa = (void *) a; | |
593 | struct wpa_scan_res **_wb = (void *) b; | |
594 | struct wpa_scan_res *wa = *_wa; | |
595 | struct wpa_scan_res *wb = *_wb; | |
596 | int wpa_a, wpa_b, maxrate_a, maxrate_b; | |
597 | ||
598 | /* WPA/WPA2 support preferred */ | |
599 | wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL || | |
600 | wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL; | |
601 | wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL || | |
602 | wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL; | |
603 | ||
604 | if (wpa_b && !wpa_a) | |
605 | return 1; | |
606 | if (!wpa_b && wpa_a) | |
607 | return -1; | |
608 | ||
609 | /* privacy support preferred */ | |
610 | if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 && | |
611 | (wb->caps & IEEE80211_CAP_PRIVACY)) | |
612 | return 1; | |
613 | if ((wa->caps & IEEE80211_CAP_PRIVACY) && | |
614 | (wb->caps & IEEE80211_CAP_PRIVACY) == 0) | |
615 | return -1; | |
616 | ||
617 | /* best/max rate preferred if signal level close enough XXX */ | |
618 | if ((wa->level && wb->level && abs(wb->level - wa->level) < 5) || | |
619 | (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) { | |
620 | maxrate_a = wpa_scan_get_max_rate(wa); | |
621 | maxrate_b = wpa_scan_get_max_rate(wb); | |
622 | if (maxrate_a != maxrate_b) | |
623 | return maxrate_b - maxrate_a; | |
624 | } | |
625 | ||
626 | /* use freq for channel preference */ | |
627 | ||
628 | /* all things being equal, use signal level; if signal levels are | |
629 | * identical, use quality values since some drivers may only report | |
630 | * that value and leave the signal level zero */ | |
631 | if (wb->level == wa->level) | |
632 | return wb->qual - wa->qual; | |
633 | return wb->level - wa->level; | |
634 | } | |
635 | ||
636 | ||
637 | /** | |
638 | * wpa_supplicant_get_scan_results - Get scan results | |
639 | * @wpa_s: Pointer to wpa_supplicant data | |
640 | * @info: Information about what was scanned or %NULL if not available | |
641 | * @new_scan: Whether a new scan was performed | |
642 | * Returns: Scan results, %NULL on failure | |
643 | * | |
644 | * This function request the current scan results from the driver and updates | |
645 | * the local BSS list wpa_s->bss. The caller is responsible for freeing the | |
646 | * results with wpa_scan_results_free(). | |
647 | */ | |
648 | struct wpa_scan_results * | |
649 | wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s, | |
650 | struct scan_info *info, int new_scan) | |
651 | { | |
652 | struct wpa_scan_results *scan_res; | |
653 | size_t i; | |
654 | ||
655 | if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME) | |
656 | scan_res = ieee80211_sta_get_scan_results(wpa_s); | |
657 | else | |
658 | scan_res = wpa_drv_get_scan_results2(wpa_s); | |
659 | if (scan_res == NULL) { | |
660 | wpa_printf(MSG_DEBUG, "Failed to get scan results"); | |
661 | return NULL; | |
662 | } | |
663 | ||
664 | qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *), | |
665 | wpa_scan_result_compar); | |
666 | ||
667 | wpa_bss_update_start(wpa_s); | |
668 | for (i = 0; i < scan_res->num; i++) | |
669 | wpa_bss_update_scan_res(wpa_s, scan_res->res[i]); | |
670 | wpa_bss_update_end(wpa_s, info, new_scan); | |
671 | ||
672 | return scan_res; | |
673 | } | |
674 | ||
675 | ||
676 | int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s) | |
677 | { | |
678 | struct wpa_scan_results *scan_res; | |
679 | scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0); | |
680 | if (scan_res == NULL) | |
681 | return -1; | |
682 | wpa_scan_results_free(scan_res); | |
683 | ||
684 | return 0; | |
685 | } | |
d1f9c410 JM |
686 | |
687 | ||
688 | void wpa_scan_results_free(struct wpa_scan_results *res) | |
689 | { | |
690 | size_t i; | |
691 | ||
692 | if (res == NULL) | |
693 | return; | |
694 | ||
695 | for (i = 0; i < res->num; i++) | |
696 | os_free(res->res[i]); | |
697 | os_free(res->res); | |
698 | os_free(res); | |
699 | } |