wpa_supplicant/autoscan.c

   1 /*
   2  * WPA Supplicant - auto scan
   3  * Copyright (c) 2012, Intel Corporation. All rights reserved.
   4  *
   5  * This software may be distributed under the terms of the BSD license.
   6  * See README for more details.
   7  */
   8
   9 #include "includes.h"
  10
  11 #include "common.h"
  12 #include "config.h"
  13 #include "wpa_supplicant_i.h"
  14 #include "bss.h"
  15 #include "scan.h"
  16 #include "autoscan.h"
  17
  18 #ifdef CONFIG_AUTOSCAN_EXPONENTIAL
  19 extern const struct autoscan_ops autoscan_exponential_ops;
  20 #endif /* CONFIG_AUTOSCAN_EXPONENTIAL */
  21
  22 static const struct autoscan_ops * autoscan_modules[] = {
  23 #ifdef CONFIG_AUTOSCAN_EXPONENTIAL
  24         &autoscan_exponential_ops,
  25 #endif /* CONFIG_AUTOSCAN_EXPONENTIAL */
  26         NULL
  27 };
  28
  29
  30 static void request_scan(struct wpa_supplicant *wpa_s)
  31 {
  32         wpa_s->scan_req = 2;
  33
  34         if (wpa_supplicant_req_sched_scan(wpa_s))
  35                 wpa_supplicant_req_scan(wpa_s, wpa_s->scan_interval, 0);
  36 }
  37
  38
  39 int autoscan_init(struct wpa_supplicant *wpa_s)
  40 {
  41         const char *name = wpa_s->conf->autoscan;
  42         const char *params;
  43         size_t nlen;
  44         int i;
  45         const struct autoscan_ops *ops = NULL;
  46
  47         if (wpa_s->autoscan && wpa_s->autoscan_priv)
  48                 return 0;
  49
  50         if (name == NULL)
  51                 return 0;
  52
  53         params = os_strchr(name, ':');
  54         if (params == NULL) {
  55                 params = "";
  56                 nlen = os_strlen(name);
  57         } else {
  58                 nlen = params - name;
  59                 params++;
  60         }
  61
  62         for (i = 0; autoscan_modules[i]; i++) {
  63                 if (os_strncmp(name, autoscan_modules[i]->name, nlen) == 0) {
  64                         ops = autoscan_modules[i];
  65                         break;
  66                 }
  67         }
  68
  69         if (ops == NULL) {
  70                 wpa_printf(MSG_ERROR, "autoscan: Could not find module "
  71                            "matching the parameter '%s'", name);
  72                 return -1;
  73         }
  74
  75         wpa_s->autoscan_params = NULL;
  76
  77         wpa_s->autoscan_priv = ops->init(wpa_s, params);
  78         if (wpa_s->autoscan_priv == NULL)
  79                 return -1;
  80         wpa_s->autoscan = ops;
  81
  82         wpa_printf(MSG_DEBUG, "autoscan: Initialized module '%s' with "
  83                    "parameters '%s'", ops->name, params);
  84
  85         /*
  86          * Cancelling existing scan requests, if any.
  87          */
  88         wpa_supplicant_cancel_sched_scan(wpa_s);
  89         wpa_supplicant_cancel_scan(wpa_s);
  90
  91         /*
  92          * Firing first scan, which will lead to call autoscan_notify_scan.
  93          */
  94         request_scan(wpa_s);
  95
  96         return 0;
  97 }
  98
  99
 100 void autoscan_deinit(struct wpa_supplicant *wpa_s)
 101 {
 102         if (wpa_s->autoscan && wpa_s->autoscan_priv) {
 103                 wpa_printf(MSG_DEBUG, "autoscan: Deinitializing module '%s'",
 104                            wpa_s->autoscan->name);
 105                 wpa_s->autoscan->deinit(wpa_s->autoscan_priv);
 106                 wpa_s->autoscan = NULL;
 107                 wpa_s->autoscan_priv = NULL;
 108
 109                 wpa_s->scan_interval = 5;
 110                 wpa_s->sched_scan_interval = 0;
 111         }
 112 }
 113
 114
 115 int autoscan_notify_scan(struct wpa_supplicant *wpa_s,
 116                          struct wpa_scan_results *scan_res)
 117 {
 118         int interval;
 119
 120         if (wpa_s->autoscan && wpa_s->autoscan_priv) {
 121                 interval = wpa_s->autoscan->notify_scan(wpa_s->autoscan_priv,
 122                                                         scan_res);
 123
 124                 if (interval <= 0)
 125                         return -1;
 126
 127                 wpa_s->scan_interval = interval;
 128                 wpa_s->sched_scan_interval = interval;
 129
 130                 request_scan(wpa_s);
 131         }
 132
 133         return 0;
 134 }