18d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt/* 28d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * WPA Supplicant - background scan and roaming module: simple 38d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * Copyright (c) 2009-2010, Jouni Malinen <j@w1.fi> 48d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * 5c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt * This software may be distributed under the terms of the BSD license. 6c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt * See README for more details. 78d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt */ 88d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 98d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "includes.h" 108d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 118d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "common.h" 128d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "eloop.h" 138d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "drivers/driver.h" 148d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "config_ssid.h" 158d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "wpa_supplicant_i.h" 168d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "driver_i.h" 178d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "scan.h" 188d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "bgscan.h" 198d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 208d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidtstruct bgscan_simple_data { 218d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt struct wpa_supplicant *wpa_s; 228d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt const struct wpa_ssid *ssid; 238d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt int scan_interval; 248d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt int signal_threshold; 258d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt int short_scan_count; /* counter for scans using short scan interval */ 26c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt int max_short_scans; /* maximum times we short-scan before back-off */ 278d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt int short_interval; /* use if signal < threshold */ 288d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt int long_interval; /* use if signal > threshold */ 29fb79edc9df1f20461e90e478363d207348213d35Dmitry Shmidt struct os_reltime last_bgscan; 308d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt}; 318d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 328d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 338d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidtstatic void bgscan_simple_timeout(void *eloop_ctx, void *timeout_ctx) 348d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt{ 358d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt struct bgscan_simple_data *data = eloop_ctx; 368d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt struct wpa_supplicant *wpa_s = data->wpa_s; 378d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt struct wpa_driver_scan_params params; 388d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 398d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt os_memset(¶ms, 0, sizeof(params)); 408d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt params.num_ssids = 1; 418d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt params.ssids[0].ssid = data->ssid->ssid; 428d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt params.ssids[0].ssid_len = data->ssid->ssid_len; 438d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt params.freqs = data->ssid->scan_freq; 448d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 458d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt /* 468d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * A more advanced bgscan module would learn about most like channels 478d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * over time and request scans only for some channels (probing others 488d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * every now and then) to reduce effect on the data connection. 498d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt */ 508d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 518d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_DEBUG, "bgscan simple: Request a background scan"); 528d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (wpa_supplicant_trigger_scan(wpa_s, ¶ms)) { 538d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_DEBUG, "bgscan simple: Failed to trigger scan"); 548d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt eloop_register_timeout(data->scan_interval, 0, 558d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt bgscan_simple_timeout, data, NULL); 568d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } else { 578d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (data->scan_interval == data->short_interval) { 588d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->short_scan_count++; 598d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt /* 608d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * Spend at most the duration of a long scan interval 618d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * scanning at the short scan interval. After that, 628d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * revert to the long scan interval. 638d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt */ 64c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt if (data->short_scan_count > data->max_short_scans) { 658d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->scan_interval = data->long_interval; 668d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_DEBUG, "bgscan simple: Backing " 678d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt "off to long scan interval"); 688d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } 69c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt } else if (data->short_scan_count > 0) { 70c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt /* 71c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt * If we lasted a long scan interval without any 72c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt * CQM triggers, decrease the short-scan count, 73c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt * which allows 1 more short-scan interval to 74c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt * occur in the future when CQM triggers. 75c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt */ 76c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt data->short_scan_count--; 778d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } 78fb79edc9df1f20461e90e478363d207348213d35Dmitry Shmidt os_get_reltime(&data->last_bgscan); 798d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } 808d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt} 818d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 828d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 838d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidtstatic int bgscan_simple_get_params(struct bgscan_simple_data *data, 848d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt const char *params) 858d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt{ 868d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt const char *pos; 878d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 888d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (params == NULL) 898d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return 0; 908d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 918d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->short_interval = atoi(params); 928d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 938d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt pos = os_strchr(params, ':'); 948d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (pos == NULL) 958d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return 0; 968d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt pos++; 978d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->signal_threshold = atoi(pos); 988d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt pos = os_strchr(pos, ':'); 998d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (pos == NULL) { 1008d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_ERROR, "bgscan simple: Missing scan interval " 1018d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt "for high signal"); 1028d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return -1; 1038d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } 1048d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt pos++; 1058d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->long_interval = atoi(pos); 1068d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1078d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return 0; 1088d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt} 1098d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1108d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1118d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidtstatic void * bgscan_simple_init(struct wpa_supplicant *wpa_s, 1128d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt const char *params, 1138d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt const struct wpa_ssid *ssid) 1148d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt{ 1158d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt struct bgscan_simple_data *data; 1168d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1178d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data = os_zalloc(sizeof(*data)); 1188d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (data == NULL) 1198d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return NULL; 1208d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->wpa_s = wpa_s; 1218d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->ssid = ssid; 1228d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (bgscan_simple_get_params(data, params) < 0) { 1238d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt os_free(data); 1248d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return NULL; 1258d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } 1268d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (data->short_interval <= 0) 1278d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->short_interval = 30; 1288d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (data->long_interval <= 0) 1298d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->long_interval = 30; 1308d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1318d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_DEBUG, "bgscan simple: Signal strength threshold %d " 1328d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt "Short bgscan interval %d Long bgscan interval %d", 1338d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->signal_threshold, data->short_interval, 1348d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->long_interval); 1358d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1368d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (data->signal_threshold && 1378d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_drv_signal_monitor(wpa_s, data->signal_threshold, 4) < 0) { 1388d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_ERROR, "bgscan simple: Failed to enable " 1398d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt "signal strength monitoring"); 1408d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } 1418d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1428d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->scan_interval = data->short_interval; 143c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt data->max_short_scans = data->long_interval / data->short_interval + 1; 1448d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (data->signal_threshold) { 1458d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt /* Poll for signal info to set initial scan interval */ 1468d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt struct wpa_signal_info siginfo; 1478d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (wpa_drv_signal_poll(wpa_s, &siginfo) == 0 && 1488d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt siginfo.current_signal >= data->signal_threshold) 1498d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->scan_interval = data->long_interval; 1508d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } 1518d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_DEBUG, "bgscan simple: Init scan interval: %d", 1528d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->scan_interval); 1538d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt eloop_register_timeout(data->scan_interval, 0, bgscan_simple_timeout, 1548d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data, NULL); 1558d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1568d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt /* 1578d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * This function is called immediately after an association, so it is 1588d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * reasonable to assume that a scan was completed recently. This makes 1598d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * us skip an immediate new scan in cases where the current signal 1608d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * level is below the bgscan threshold. 1618d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt */ 162fb79edc9df1f20461e90e478363d207348213d35Dmitry Shmidt os_get_reltime(&data->last_bgscan); 1638d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1648d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return data; 1658d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt} 1668d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1678d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1688d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidtstatic void bgscan_simple_deinit(void *priv) 1698d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt{ 1708d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt struct bgscan_simple_data *data = priv; 1718d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt eloop_cancel_timeout(bgscan_simple_timeout, data, NULL); 1728d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (data->signal_threshold) 1738d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_drv_signal_monitor(data->wpa_s, 0, 0); 1748d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt os_free(data); 1758d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt} 1768d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1778d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1788d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidtstatic int bgscan_simple_notify_scan(void *priv, 1798d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt struct wpa_scan_results *scan_res) 1808d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt{ 1818d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt struct bgscan_simple_data *data = priv; 1828d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1838d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_DEBUG, "bgscan simple: scan result notification"); 1848d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1858d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt eloop_cancel_timeout(bgscan_simple_timeout, data, NULL); 1868d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt eloop_register_timeout(data->scan_interval, 0, bgscan_simple_timeout, 1878d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data, NULL); 1888d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1898d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt /* 1908d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * A more advanced bgscan could process scan results internally, select 1918d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * the BSS and request roam if needed. This sample uses the existing 1928d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * BSS/ESS selection routine. Change this to return 1 if selection is 1938d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * done inside the bgscan module. 1948d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt */ 1958d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1968d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return 0; 1978d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt} 1988d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 1998d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 2008d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidtstatic void bgscan_simple_notify_beacon_loss(void *priv) 2018d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt{ 2028d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_DEBUG, "bgscan simple: beacon loss"); 2038d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt /* TODO: speed up background scanning */ 2048d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt} 2058d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 2068d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 2078d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidtstatic void bgscan_simple_notify_signal_change(void *priv, int above, 2088d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt int current_signal, 2098d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt int current_noise, 2108d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt int current_txrate) 2118d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt{ 2128d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt struct bgscan_simple_data *data = priv; 2138d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt int scan = 0; 214fb79edc9df1f20461e90e478363d207348213d35Dmitry Shmidt struct os_reltime now; 2158d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 2168d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (data->short_interval == data->long_interval || 2178d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->signal_threshold == 0) 2188d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return; 2198d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 2208d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_DEBUG, "bgscan simple: signal level changed " 2218d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt "(above=%d current_signal=%d current_noise=%d " 2228d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt "current_txrate=%d))", above, current_signal, 2238d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt current_noise, current_txrate); 2248d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (data->scan_interval == data->long_interval && !above) { 2258d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_DEBUG, "bgscan simple: Start using short " 2268d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt "bgscan interval"); 2278d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->scan_interval = data->short_interval; 228fb79edc9df1f20461e90e478363d207348213d35Dmitry Shmidt os_get_reltime(&now); 229c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt if (now.sec > data->last_bgscan.sec + 1 && 230c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt data->short_scan_count <= data->max_short_scans) 231c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt /* 232c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt * If we haven't just previously (<1 second ago) 233c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt * performed a scan, and we haven't depleted our 234c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt * budget for short-scans, perform a scan 235c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt * immediately. 236c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt */ 2378d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt scan = 1; 2388d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt else if (data->last_bgscan.sec + data->long_interval > 2398d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt now.sec + data->scan_interval) { 2408d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt /* 2418d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * Restart scan interval timer if currently scheduled 2428d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * scan is too far in the future. 2438d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt */ 2448d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt eloop_cancel_timeout(bgscan_simple_timeout, data, 2458d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt NULL); 2468d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt eloop_register_timeout(data->scan_interval, 0, 2478d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt bgscan_simple_timeout, data, 2488d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt NULL); 2498d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } 2508d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } else if (data->scan_interval == data->short_interval && above) { 2518d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_DEBUG, "bgscan simple: Start using long bgscan " 2528d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt "interval"); 2538d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt data->scan_interval = data->long_interval; 2548d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt eloop_cancel_timeout(bgscan_simple_timeout, data, NULL); 2558d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt eloop_register_timeout(data->scan_interval, 0, 2568d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt bgscan_simple_timeout, data, NULL); 2578d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } else if (!above) { 2588d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt /* 2598d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * Signal dropped further 4 dB. Request a new scan if we have 2608d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * not yet scanned in a while. 2618d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt */ 262fb79edc9df1f20461e90e478363d207348213d35Dmitry Shmidt os_get_reltime(&now); 2638d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (now.sec > data->last_bgscan.sec + 10) 2648d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt scan = 1; 2658d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } 2668d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 2678d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (scan) { 2688d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt wpa_printf(MSG_DEBUG, "bgscan simple: Trigger immediate scan"); 2698d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt eloop_cancel_timeout(bgscan_simple_timeout, data, NULL); 2708d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt eloop_register_timeout(0, 0, bgscan_simple_timeout, data, 2718d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt NULL); 2728d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } 2738d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt} 2748d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 2758d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 2768d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidtconst struct bgscan_ops bgscan_simple_ops = { 2778d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt .name = "simple", 2788d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt .init = bgscan_simple_init, 2798d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt .deinit = bgscan_simple_deinit, 2808d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt .notify_scan = bgscan_simple_notify_scan, 2818d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt .notify_beacon_loss = bgscan_simple_notify_beacon_loss, 2828d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt .notify_signal_change = bgscan_simple_notify_signal_change, 2838d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt}; 284