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c4d71c25 JM |
1 | /* |
2 | * WPA Supplicant - background scan and roaming module: learn | |
3 | * Copyright (c) 2009-2010, Jouni Malinen <j@w1.fi> | |
4 | * | |
0f3d578e JM |
5 | * This software may be distributed under the terms of the BSD license. |
6 | * See README for more details. | |
c4d71c25 JM |
7 | */ |
8 | ||
9 | #include "includes.h" | |
10 | ||
11 | #include "common.h" | |
12 | #include "eloop.h" | |
fc480e88 JM |
13 | #include "list.h" |
14 | #include "common/ieee802_11_defs.h" | |
c4d71c25 JM |
15 | #include "drivers/driver.h" |
16 | #include "config_ssid.h" | |
17 | #include "wpa_supplicant_i.h" | |
18 | #include "driver_i.h" | |
19 | #include "scan.h" | |
20 | #include "bgscan.h" | |
21 | ||
fc480e88 JM |
22 | struct bgscan_learn_bss { |
23 | struct dl_list list; | |
24 | u8 bssid[ETH_ALEN]; | |
25 | int freq; | |
3b7442e5 JM |
26 | u8 *neigh; /* num_neigh * ETH_ALEN buffer */ |
27 | size_t num_neigh; | |
fc480e88 JM |
28 | }; |
29 | ||
c4d71c25 JM |
30 | struct bgscan_learn_data { |
31 | struct wpa_supplicant *wpa_s; | |
32 | const struct wpa_ssid *ssid; | |
33 | int scan_interval; | |
34 | int signal_threshold; | |
35 | int short_interval; /* use if signal < threshold */ | |
36 | int long_interval; /* use if signal > threshold */ | |
e72a001b | 37 | struct os_reltime last_bgscan; |
2e8d6ae3 | 38 | char *fname; |
fc480e88 | 39 | struct dl_list bss; |
2e2a8d07 JM |
40 | int *supp_freqs; |
41 | int probe_idx; | |
c4d71c25 JM |
42 | }; |
43 | ||
44 | ||
3b7442e5 JM |
45 | static void bss_free(struct bgscan_learn_bss *bss) |
46 | { | |
47 | os_free(bss->neigh); | |
48 | os_free(bss); | |
49 | } | |
50 | ||
51 | ||
52 | static int bssid_in_array(u8 *array, size_t array_len, const u8 *bssid) | |
53 | { | |
54 | size_t i; | |
55 | ||
56 | if (array == NULL || array_len == 0) | |
57 | return 0; | |
58 | ||
59 | for (i = 0; i < array_len; i++) { | |
60 | if (os_memcmp(array + i * ETH_ALEN, bssid, ETH_ALEN) == 0) | |
61 | return 1; | |
62 | } | |
63 | ||
64 | return 0; | |
65 | } | |
66 | ||
67 | ||
68 | static void bgscan_learn_add_neighbor(struct bgscan_learn_bss *bss, | |
69 | const u8 *bssid) | |
70 | { | |
71 | u8 *n; | |
72 | ||
73 | if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0) | |
74 | return; | |
75 | if (bssid_in_array(bss->neigh, bss->num_neigh, bssid)) | |
76 | return; | |
77 | ||
067ffa26 | 78 | n = os_realloc_array(bss->neigh, bss->num_neigh + 1, ETH_ALEN); |
3b7442e5 JM |
79 | if (n == NULL) |
80 | return; | |
81 | ||
82 | os_memcpy(n + bss->num_neigh * ETH_ALEN, bssid, ETH_ALEN); | |
83 | bss->neigh = n; | |
84 | bss->num_neigh++; | |
3b7442e5 JM |
85 | } |
86 | ||
87 | ||
fc480e88 JM |
88 | static struct bgscan_learn_bss * bgscan_learn_get_bss( |
89 | struct bgscan_learn_data *data, const u8 *bssid) | |
90 | { | |
91 | struct bgscan_learn_bss *bss; | |
92 | ||
93 | dl_list_for_each(bss, &data->bss, struct bgscan_learn_bss, list) { | |
94 | if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0) | |
95 | return bss; | |
96 | } | |
97 | return NULL; | |
98 | } | |
99 | ||
100 | ||
2e8d6ae3 JM |
101 | static int bgscan_learn_load(struct bgscan_learn_data *data) |
102 | { | |
103 | FILE *f; | |
104 | char buf[128]; | |
3b7442e5 | 105 | struct bgscan_learn_bss *bss; |
2e8d6ae3 JM |
106 | |
107 | if (data->fname == NULL) | |
108 | return 0; | |
109 | ||
110 | f = fopen(data->fname, "r"); | |
111 | if (f == NULL) | |
112 | return 0; | |
113 | ||
114 | wpa_printf(MSG_DEBUG, "bgscan learn: Loading data from %s", | |
115 | data->fname); | |
116 | ||
117 | if (fgets(buf, sizeof(buf), f) == NULL || | |
118 | os_strncmp(buf, "wpa_supplicant-bgscan-learn\n", 28) != 0) { | |
119 | wpa_printf(MSG_INFO, "bgscan learn: Invalid data file %s", | |
120 | data->fname); | |
121 | fclose(f); | |
122 | return -1; | |
123 | } | |
124 | ||
fc480e88 JM |
125 | while (fgets(buf, sizeof(buf), f)) { |
126 | if (os_strncmp(buf, "BSS ", 4) == 0) { | |
fc480e88 JM |
127 | bss = os_zalloc(sizeof(*bss)); |
128 | if (!bss) | |
129 | continue; | |
130 | if (hwaddr_aton(buf + 4, bss->bssid) < 0) { | |
3b7442e5 | 131 | bss_free(bss); |
fc480e88 JM |
132 | continue; |
133 | } | |
134 | bss->freq = atoi(buf + 4 + 18); | |
135 | dl_list_add(&data->bss, &bss->list); | |
136 | wpa_printf(MSG_DEBUG, "bgscan learn: Loaded BSS " | |
137 | "entry: " MACSTR " freq=%d", | |
138 | MAC2STR(bss->bssid), bss->freq); | |
139 | } | |
3b7442e5 JM |
140 | |
141 | if (os_strncmp(buf, "NEIGHBOR ", 9) == 0) { | |
142 | u8 addr[ETH_ALEN]; | |
143 | ||
144 | if (hwaddr_aton(buf + 9, addr) < 0) | |
145 | continue; | |
146 | bss = bgscan_learn_get_bss(data, addr); | |
147 | if (bss == NULL) | |
148 | continue; | |
149 | if (hwaddr_aton(buf + 9 + 18, addr) < 0) | |
150 | continue; | |
151 | ||
152 | bgscan_learn_add_neighbor(bss, addr); | |
153 | } | |
fc480e88 JM |
154 | } |
155 | ||
2e8d6ae3 JM |
156 | fclose(f); |
157 | return 0; | |
158 | } | |
159 | ||
160 | ||
161 | static void bgscan_learn_save(struct bgscan_learn_data *data) | |
162 | { | |
163 | FILE *f; | |
fc480e88 | 164 | struct bgscan_learn_bss *bss; |
2e8d6ae3 JM |
165 | |
166 | if (data->fname == NULL) | |
167 | return; | |
168 | ||
169 | wpa_printf(MSG_DEBUG, "bgscan learn: Saving data to %s", | |
170 | data->fname); | |
171 | ||
172 | f = fopen(data->fname, "w"); | |
173 | if (f == NULL) | |
174 | return; | |
175 | fprintf(f, "wpa_supplicant-bgscan-learn\n"); | |
176 | ||
fc480e88 JM |
177 | dl_list_for_each(bss, &data->bss, struct bgscan_learn_bss, list) { |
178 | fprintf(f, "BSS " MACSTR " %d\n", | |
179 | MAC2STR(bss->bssid), bss->freq); | |
180 | } | |
181 | ||
3b7442e5 JM |
182 | dl_list_for_each(bss, &data->bss, struct bgscan_learn_bss, list) { |
183 | size_t i; | |
184 | for (i = 0; i < bss->num_neigh; i++) { | |
185 | fprintf(f, "NEIGHBOR " MACSTR " " MACSTR "\n", | |
186 | MAC2STR(bss->bssid), | |
187 | MAC2STR(bss->neigh + i * ETH_ALEN)); | |
188 | } | |
189 | } | |
190 | ||
2e8d6ae3 JM |
191 | fclose(f); |
192 | } | |
193 | ||
194 | ||
fc480e88 JM |
195 | static int in_array(int *array, int val) |
196 | { | |
197 | int i; | |
198 | ||
199 | if (array == NULL) | |
200 | return 0; | |
201 | ||
202 | for (i = 0; array[i]; i++) { | |
203 | if (array[i] == val) | |
204 | return 1; | |
205 | } | |
206 | ||
207 | return 0; | |
208 | } | |
209 | ||
210 | ||
211 | static int * bgscan_learn_get_freqs(struct bgscan_learn_data *data, | |
212 | size_t *count) | |
213 | { | |
214 | struct bgscan_learn_bss *bss; | |
215 | int *freqs = NULL, *n; | |
216 | ||
217 | *count = 0; | |
218 | ||
219 | dl_list_for_each(bss, &data->bss, struct bgscan_learn_bss, list) { | |
220 | if (in_array(freqs, bss->freq)) | |
221 | continue; | |
067ffa26 | 222 | n = os_realloc_array(freqs, *count + 2, sizeof(int)); |
fc480e88 JM |
223 | if (n == NULL) |
224 | return freqs; | |
225 | freqs = n; | |
226 | freqs[*count] = bss->freq; | |
227 | (*count)++; | |
228 | freqs[*count] = 0; | |
229 | } | |
230 | ||
231 | return freqs; | |
232 | } | |
233 | ||
234 | ||
2e2a8d07 JM |
235 | static int * bgscan_learn_get_probe_freq(struct bgscan_learn_data *data, |
236 | int *freqs, size_t count) | |
237 | { | |
238 | int idx, *n; | |
239 | ||
240 | if (data->supp_freqs == NULL) | |
241 | return freqs; | |
242 | ||
3e06180f EP |
243 | idx = data->probe_idx; |
244 | do { | |
2e2a8d07 JM |
245 | if (!in_array(freqs, data->supp_freqs[idx])) { |
246 | wpa_printf(MSG_DEBUG, "bgscan learn: Probe new freq " | |
247 | "%u", data->supp_freqs[idx]); | |
3e06180f EP |
248 | data->probe_idx = idx + 1; |
249 | if (data->supp_freqs[data->probe_idx] == 0) | |
250 | data->probe_idx = 0; | |
067ffa26 | 251 | n = os_realloc_array(freqs, count + 2, sizeof(int)); |
2e2a8d07 JM |
252 | if (n == NULL) |
253 | return freqs; | |
254 | freqs = n; | |
255 | freqs[count] = data->supp_freqs[idx]; | |
256 | count++; | |
257 | freqs[count] = 0; | |
258 | break; | |
259 | } | |
260 | ||
261 | idx++; | |
3e06180f EP |
262 | if (data->supp_freqs[idx] == 0) |
263 | idx = 0; | |
264 | } while (idx != data->probe_idx); | |
2e2a8d07 JM |
265 | |
266 | return freqs; | |
267 | } | |
268 | ||
269 | ||
c4d71c25 JM |
270 | static void bgscan_learn_timeout(void *eloop_ctx, void *timeout_ctx) |
271 | { | |
272 | struct bgscan_learn_data *data = eloop_ctx; | |
273 | struct wpa_supplicant *wpa_s = data->wpa_s; | |
274 | struct wpa_driver_scan_params params; | |
fc480e88 | 275 | int *freqs = NULL; |
2e2a8d07 JM |
276 | size_t count, i; |
277 | char msg[100], *pos; | |
c4d71c25 JM |
278 | |
279 | os_memset(¶ms, 0, sizeof(params)); | |
280 | params.num_ssids = 1; | |
281 | params.ssids[0].ssid = data->ssid->ssid; | |
282 | params.ssids[0].ssid_len = data->ssid->ssid_len; | |
fc480e88 JM |
283 | if (data->ssid->scan_freq) |
284 | params.freqs = data->ssid->scan_freq; | |
285 | else { | |
286 | freqs = bgscan_learn_get_freqs(data, &count); | |
287 | wpa_printf(MSG_DEBUG, "bgscan learn: BSSes in this ESS have " | |
288 | "been seen on %u channels", (unsigned int) count); | |
2e2a8d07 JM |
289 | freqs = bgscan_learn_get_probe_freq(data, freqs, count); |
290 | ||
291 | msg[0] = '\0'; | |
292 | pos = msg; | |
293 | for (i = 0; freqs && freqs[i]; i++) { | |
294 | int ret; | |
295 | ret = os_snprintf(pos, msg + sizeof(msg) - pos, " %d", | |
296 | freqs[i]); | |
d85e1fc8 | 297 | if (os_snprintf_error(msg + sizeof(msg) - pos, ret)) |
2e2a8d07 JM |
298 | break; |
299 | pos += ret; | |
300 | } | |
301 | pos[0] = '\0'; | |
302 | wpa_printf(MSG_DEBUG, "bgscan learn: Scanning frequencies:%s", | |
303 | msg); | |
fc480e88 JM |
304 | params.freqs = freqs; |
305 | } | |
c4d71c25 JM |
306 | |
307 | wpa_printf(MSG_DEBUG, "bgscan learn: Request a background scan"); | |
308 | if (wpa_supplicant_trigger_scan(wpa_s, ¶ms)) { | |
309 | wpa_printf(MSG_DEBUG, "bgscan learn: Failed to trigger scan"); | |
310 | eloop_register_timeout(data->scan_interval, 0, | |
311 | bgscan_learn_timeout, data, NULL); | |
312 | } else | |
e72a001b | 313 | os_get_reltime(&data->last_bgscan); |
fc480e88 | 314 | os_free(freqs); |
c4d71c25 JM |
315 | } |
316 | ||
317 | ||
318 | static int bgscan_learn_get_params(struct bgscan_learn_data *data, | |
319 | const char *params) | |
320 | { | |
321 | const char *pos; | |
322 | ||
323 | if (params == NULL) | |
324 | return 0; | |
325 | ||
326 | data->short_interval = atoi(params); | |
327 | ||
328 | pos = os_strchr(params, ':'); | |
329 | if (pos == NULL) | |
330 | return 0; | |
331 | pos++; | |
332 | data->signal_threshold = atoi(pos); | |
333 | pos = os_strchr(pos, ':'); | |
334 | if (pos == NULL) { | |
335 | wpa_printf(MSG_ERROR, "bgscan learn: Missing scan interval " | |
336 | "for high signal"); | |
337 | return -1; | |
338 | } | |
339 | pos++; | |
340 | data->long_interval = atoi(pos); | |
2e8d6ae3 JM |
341 | pos = os_strchr(pos, ':'); |
342 | if (pos) { | |
343 | pos++; | |
344 | data->fname = os_strdup(pos); | |
345 | } | |
c4d71c25 JM |
346 | |
347 | return 0; | |
348 | } | |
349 | ||
350 | ||
2e2a8d07 JM |
351 | static int * bgscan_learn_get_supp_freqs(struct wpa_supplicant *wpa_s) |
352 | { | |
353 | struct hostapd_hw_modes *modes; | |
2e2a8d07 JM |
354 | int i, j, *freqs = NULL, *n; |
355 | size_t count = 0; | |
356 | ||
6bf731e8 CL |
357 | modes = wpa_s->hw.modes; |
358 | if (modes == NULL) | |
2e2a8d07 JM |
359 | return NULL; |
360 | ||
6bf731e8 | 361 | for (i = 0; i < wpa_s->hw.num_modes; i++) { |
2e2a8d07 JM |
362 | for (j = 0; j < modes[i].num_channels; j++) { |
363 | if (modes[i].channels[j].flag & HOSTAPD_CHAN_DISABLED) | |
364 | continue; | |
7dab1193 EP |
365 | /* some hw modes (e.g. 11b & 11g) contain same freqs */ |
366 | if (in_array(freqs, modes[i].channels[j].freq)) | |
367 | continue; | |
067ffa26 | 368 | n = os_realloc_array(freqs, count + 2, sizeof(int)); |
6bf731e8 | 369 | if (n == NULL) |
2e2a8d07 JM |
370 | continue; |
371 | ||
372 | freqs = n; | |
373 | freqs[count] = modes[i].channels[j].freq; | |
374 | count++; | |
375 | freqs[count] = 0; | |
376 | } | |
2e2a8d07 | 377 | } |
2e2a8d07 JM |
378 | |
379 | return freqs; | |
380 | } | |
381 | ||
382 | ||
c4d71c25 JM |
383 | static void * bgscan_learn_init(struct wpa_supplicant *wpa_s, |
384 | const char *params, | |
385 | const struct wpa_ssid *ssid) | |
386 | { | |
387 | struct bgscan_learn_data *data; | |
388 | ||
389 | data = os_zalloc(sizeof(*data)); | |
390 | if (data == NULL) | |
391 | return NULL; | |
fc480e88 | 392 | dl_list_init(&data->bss); |
c4d71c25 JM |
393 | data->wpa_s = wpa_s; |
394 | data->ssid = ssid; | |
395 | if (bgscan_learn_get_params(data, params) < 0) { | |
2e8d6ae3 | 396 | os_free(data->fname); |
c4d71c25 JM |
397 | os_free(data); |
398 | return NULL; | |
399 | } | |
400 | if (data->short_interval <= 0) | |
401 | data->short_interval = 30; | |
402 | if (data->long_interval <= 0) | |
403 | data->long_interval = 30; | |
404 | ||
2e8d6ae3 JM |
405 | if (bgscan_learn_load(data) < 0) { |
406 | os_free(data->fname); | |
407 | os_free(data); | |
408 | return NULL; | |
409 | } | |
410 | ||
c4d71c25 JM |
411 | wpa_printf(MSG_DEBUG, "bgscan learn: Signal strength threshold %d " |
412 | "Short bgscan interval %d Long bgscan interval %d", | |
413 | data->signal_threshold, data->short_interval, | |
414 | data->long_interval); | |
415 | ||
416 | if (data->signal_threshold && | |
417 | wpa_drv_signal_monitor(wpa_s, data->signal_threshold, 4) < 0) { | |
418 | wpa_printf(MSG_ERROR, "bgscan learn: Failed to enable " | |
419 | "signal strength monitoring"); | |
420 | } | |
421 | ||
2e2a8d07 | 422 | data->supp_freqs = bgscan_learn_get_supp_freqs(wpa_s); |
c4d71c25 | 423 | data->scan_interval = data->short_interval; |
f4c73ae6 ES |
424 | if (data->signal_threshold) { |
425 | /* Poll for signal info to set initial scan interval */ | |
426 | struct wpa_signal_info siginfo; | |
427 | if (wpa_drv_signal_poll(wpa_s, &siginfo) == 0 && | |
428 | siginfo.current_signal >= data->signal_threshold) | |
429 | data->scan_interval = data->long_interval; | |
430 | } | |
431 | ||
c4d71c25 JM |
432 | eloop_register_timeout(data->scan_interval, 0, bgscan_learn_timeout, |
433 | data, NULL); | |
9ff80a10 JM |
434 | |
435 | /* | |
436 | * This function is called immediately after an association, so it is | |
437 | * reasonable to assume that a scan was completed recently. This makes | |
438 | * us skip an immediate new scan in cases where the current signal | |
439 | * level is below the bgscan threshold. | |
440 | */ | |
e72a001b | 441 | os_get_reltime(&data->last_bgscan); |
9ff80a10 | 442 | |
c4d71c25 JM |
443 | return data; |
444 | } | |
445 | ||
446 | ||
447 | static void bgscan_learn_deinit(void *priv) | |
448 | { | |
449 | struct bgscan_learn_data *data = priv; | |
fc480e88 JM |
450 | struct bgscan_learn_bss *bss, *n; |
451 | ||
2e8d6ae3 | 452 | bgscan_learn_save(data); |
c4d71c25 JM |
453 | eloop_cancel_timeout(bgscan_learn_timeout, data, NULL); |
454 | if (data->signal_threshold) | |
455 | wpa_drv_signal_monitor(data->wpa_s, 0, 0); | |
2e8d6ae3 | 456 | os_free(data->fname); |
fc480e88 JM |
457 | dl_list_for_each_safe(bss, n, &data->bss, struct bgscan_learn_bss, |
458 | list) { | |
459 | dl_list_del(&bss->list); | |
3b7442e5 | 460 | bss_free(bss); |
fc480e88 | 461 | } |
2e2a8d07 | 462 | os_free(data->supp_freqs); |
c4d71c25 JM |
463 | os_free(data); |
464 | } | |
465 | ||
466 | ||
fc480e88 JM |
467 | static int bgscan_learn_bss_match(struct bgscan_learn_data *data, |
468 | struct wpa_scan_res *bss) | |
469 | { | |
470 | const u8 *ie; | |
471 | ||
472 | ie = wpa_scan_get_ie(bss, WLAN_EID_SSID); | |
473 | if (ie == NULL) | |
474 | return 0; | |
475 | ||
476 | if (data->ssid->ssid_len != ie[1] || | |
477 | os_memcmp(data->ssid->ssid, ie + 2, ie[1]) != 0) | |
478 | return 0; /* SSID mismatch */ | |
479 | ||
480 | return 1; | |
481 | } | |
482 | ||
483 | ||
c4d71c25 JM |
484 | static int bgscan_learn_notify_scan(void *priv, |
485 | struct wpa_scan_results *scan_res) | |
486 | { | |
487 | struct bgscan_learn_data *data = priv; | |
3b7442e5 JM |
488 | size_t i, j; |
489 | #define MAX_BSS 50 | |
490 | u8 bssid[MAX_BSS * ETH_ALEN]; | |
491 | size_t num_bssid = 0; | |
c4d71c25 JM |
492 | |
493 | wpa_printf(MSG_DEBUG, "bgscan learn: scan result notification"); | |
494 | ||
495 | eloop_cancel_timeout(bgscan_learn_timeout, data, NULL); | |
496 | eloop_register_timeout(data->scan_interval, 0, bgscan_learn_timeout, | |
497 | data, NULL); | |
498 | ||
3b7442e5 JM |
499 | for (i = 0; i < scan_res->num; i++) { |
500 | struct wpa_scan_res *res = scan_res->res[i]; | |
501 | if (!bgscan_learn_bss_match(data, res)) | |
502 | continue; | |
503 | ||
504 | if (num_bssid < MAX_BSS) { | |
505 | os_memcpy(bssid + num_bssid * ETH_ALEN, res->bssid, | |
506 | ETH_ALEN); | |
507 | num_bssid++; | |
508 | } | |
509 | } | |
510 | wpa_printf(MSG_DEBUG, "bgscan learn: %u matching BSSes in scan " | |
511 | "results", (unsigned int) num_bssid); | |
512 | ||
fc480e88 JM |
513 | for (i = 0; i < scan_res->num; i++) { |
514 | struct wpa_scan_res *res = scan_res->res[i]; | |
515 | struct bgscan_learn_bss *bss; | |
516 | ||
517 | if (!bgscan_learn_bss_match(data, res)) | |
518 | continue; | |
3b7442e5 | 519 | |
fc480e88 JM |
520 | bss = bgscan_learn_get_bss(data, res->bssid); |
521 | if (bss && bss->freq != res->freq) { | |
522 | wpa_printf(MSG_DEBUG, "bgscan learn: Update BSS " | |
523 | MACSTR " freq %d -> %d", | |
524 | MAC2STR(res->bssid), bss->freq, res->freq); | |
525 | bss->freq = res->freq; | |
526 | } else if (!bss) { | |
527 | wpa_printf(MSG_DEBUG, "bgscan learn: Add BSS " MACSTR | |
528 | " freq=%d", MAC2STR(res->bssid), res->freq); | |
529 | bss = os_zalloc(sizeof(*bss)); | |
530 | if (!bss) | |
531 | continue; | |
532 | os_memcpy(bss->bssid, res->bssid, ETH_ALEN); | |
533 | bss->freq = res->freq; | |
534 | dl_list_add(&data->bss, &bss->list); | |
535 | } | |
3b7442e5 JM |
536 | |
537 | for (j = 0; j < num_bssid; j++) { | |
538 | u8 *addr = bssid + j * ETH_ALEN; | |
539 | bgscan_learn_add_neighbor(bss, addr); | |
540 | } | |
fc480e88 JM |
541 | } |
542 | ||
c4d71c25 JM |
543 | /* |
544 | * A more advanced bgscan could process scan results internally, select | |
545 | * the BSS and request roam if needed. This sample uses the existing | |
546 | * BSS/ESS selection routine. Change this to return 1 if selection is | |
547 | * done inside the bgscan module. | |
548 | */ | |
549 | ||
550 | return 0; | |
551 | } | |
552 | ||
553 | ||
554 | static void bgscan_learn_notify_beacon_loss(void *priv) | |
555 | { | |
556 | wpa_printf(MSG_DEBUG, "bgscan learn: beacon loss"); | |
557 | /* TODO: speed up background scanning */ | |
558 | } | |
559 | ||
560 | ||
60a972a6 | 561 | static void bgscan_learn_notify_signal_change(void *priv, int above, |
174fa789 PS |
562 | int current_signal, |
563 | int current_noise, | |
564 | int current_txrate) | |
c4d71c25 JM |
565 | { |
566 | struct bgscan_learn_data *data = priv; | |
266c828e | 567 | int scan = 0; |
e72a001b | 568 | struct os_reltime now; |
c4d71c25 JM |
569 | |
570 | if (data->short_interval == data->long_interval || | |
571 | data->signal_threshold == 0) | |
572 | return; | |
573 | ||
574 | wpa_printf(MSG_DEBUG, "bgscan learn: signal level changed " | |
174fa789 PS |
575 | "(above=%d current_signal=%d current_noise=%d " |
576 | "current_txrate=%d)", above, current_signal, | |
577 | current_noise, current_txrate); | |
c4d71c25 | 578 | if (data->scan_interval == data->long_interval && !above) { |
9ff80a10 JM |
579 | wpa_printf(MSG_DEBUG, "bgscan learn: Start using short bgscan " |
580 | "interval"); | |
c4d71c25 | 581 | data->scan_interval = data->short_interval; |
e72a001b | 582 | os_get_reltime(&now); |
9ff80a10 JM |
583 | if (now.sec > data->last_bgscan.sec + 1) |
584 | scan = 1; | |
c4d71c25 JM |
585 | } else if (data->scan_interval == data->short_interval && above) { |
586 | wpa_printf(MSG_DEBUG, "bgscan learn: Start using long bgscan " | |
587 | "interval"); | |
588 | data->scan_interval = data->long_interval; | |
589 | eloop_cancel_timeout(bgscan_learn_timeout, data, NULL); | |
590 | eloop_register_timeout(data->scan_interval, 0, | |
591 | bgscan_learn_timeout, data, NULL); | |
592 | } else if (!above) { | |
c4d71c25 JM |
593 | /* |
594 | * Signal dropped further 4 dB. Request a new scan if we have | |
595 | * not yet scanned in a while. | |
596 | */ | |
e72a001b | 597 | os_get_reltime(&now); |
9ff80a10 JM |
598 | if (now.sec > data->last_bgscan.sec + 10) |
599 | scan = 1; | |
600 | } | |
601 | ||
602 | if (scan) { | |
603 | wpa_printf(MSG_DEBUG, "bgscan learn: Trigger immediate scan"); | |
604 | eloop_cancel_timeout(bgscan_learn_timeout, data, NULL); | |
605 | eloop_register_timeout(0, 0, bgscan_learn_timeout, data, NULL); | |
c4d71c25 JM |
606 | } |
607 | } | |
608 | ||
609 | ||
610 | const struct bgscan_ops bgscan_learn_ops = { | |
611 | .name = "learn", | |
612 | .init = bgscan_learn_init, | |
613 | .deinit = bgscan_learn_deinit, | |
614 | .notify_scan = bgscan_learn_notify_scan, | |
615 | .notify_beacon_loss = bgscan_learn_notify_beacon_loss, | |
616 | .notify_signal_change = bgscan_learn_notify_signal_change, | |
617 | }; |