1 /*
2  * WPA Supplicant - auto scan
3  * Copyright (c) 2012, Intel Corporation. All rights reserved.
4  * Copyright 2015	Intel Deutschland GmbH
5  *
6  * This software may be distributed under the terms of the BSD license.
7  * See README for more details.
8  */
9 
10 #include "includes.h"
11 
12 #include "common.h"
13 #include "config.h"
14 #include "wpa_supplicant_i.h"
15 #include "bss.h"
16 #include "scan.h"
17 #include "autoscan.h"
18 
19 
20 static const struct autoscan_ops * autoscan_modules[] = {
21 #ifdef CONFIG_AUTOSCAN_EXPONENTIAL
22 	&autoscan_exponential_ops,
23 #endif /* CONFIG_AUTOSCAN_EXPONENTIAL */
24 #ifdef CONFIG_AUTOSCAN_PERIODIC
25 	&autoscan_periodic_ops,
26 #endif /* CONFIG_AUTOSCAN_PERIODIC */
27 	NULL
28 };
29 
30 
31 static void request_scan(struct wpa_supplicant *wpa_s)
32 {
33 	wpa_s->scan_req = MANUAL_SCAN_REQ;
34 
35 	if (wpa_supplicant_req_sched_scan(wpa_s))
36 		wpa_supplicant_req_scan(wpa_s, wpa_s->scan_interval, 0);
37 }
38 
39 
40 int autoscan_init(struct wpa_supplicant *wpa_s, int req_scan)
41 {
42 	const char *name = wpa_s->conf->autoscan;
43 	const char *params;
44 	size_t nlen;
45 	int i;
46 	const struct autoscan_ops *ops = NULL;
47 	struct sched_scan_plan *scan_plans;
48 
49 	/* Give preference to scheduled scan plans if supported/configured */
50 	if (wpa_s->sched_scan_plans)
51 		return 0;
52 
53 	if (wpa_s->autoscan && wpa_s->autoscan_priv)
54 		return 0;
55 
56 	if (name == NULL)
57 		return 0;
58 
59 	params = os_strchr(name, ':');
60 	if (params == NULL) {
61 		params = "";
62 		nlen = os_strlen(name);
63 	} else {
64 		nlen = params - name;
65 		params++;
66 	}
67 
68 	for (i = 0; autoscan_modules[i]; i++) {
69 		if (os_strncmp(name, autoscan_modules[i]->name, nlen) == 0) {
70 			ops = autoscan_modules[i];
71 			break;
72 		}
73 	}
74 
75 	if (ops == NULL) {
76 		wpa_printf(MSG_ERROR, "autoscan: Could not find module "
77 			   "matching the parameter '%s'", name);
78 		return -1;
79 	}
80 
81 	scan_plans = os_malloc(sizeof(*wpa_s->sched_scan_plans));
82 	if (!scan_plans)
83 		return -1;
84 
85 	wpa_s->autoscan_params = NULL;
86 
87 	wpa_s->autoscan_priv = ops->init(wpa_s, params);
88 	if (!wpa_s->autoscan_priv) {
89 		os_free(scan_plans);
90 		return -1;
91 	}
92 
93 	scan_plans[0].interval = 5;
94 	scan_plans[0].iterations = 0;
95 	os_free(wpa_s->sched_scan_plans);
96 	wpa_s->sched_scan_plans = scan_plans;
97 	wpa_s->sched_scan_plans_num = 1;
98 	wpa_s->autoscan = ops;
99 
100 	wpa_printf(MSG_DEBUG, "autoscan: Initialized module '%s' with "
101 		   "parameters '%s'", ops->name, params);
102 	if (!req_scan)
103 		return 0;
104 
105 	/*
106 	 * Cancelling existing scan requests, if any.
107 	 */
108 	wpa_supplicant_cancel_sched_scan(wpa_s);
109 	wpa_supplicant_cancel_scan(wpa_s);
110 
111 	/*
112 	 * Firing first scan, which will lead to call autoscan_notify_scan.
113 	 */
114 	request_scan(wpa_s);
115 
116 	return 0;
117 }
118 
119 
120 void autoscan_deinit(struct wpa_supplicant *wpa_s)
121 {
122 	if (wpa_s->autoscan && wpa_s->autoscan_priv) {
123 		wpa_printf(MSG_DEBUG, "autoscan: Deinitializing module '%s'",
124 			   wpa_s->autoscan->name);
125 		wpa_s->autoscan->deinit(wpa_s->autoscan_priv);
126 		wpa_s->autoscan = NULL;
127 		wpa_s->autoscan_priv = NULL;
128 
129 		wpa_s->scan_interval = 5;
130 
131 		os_free(wpa_s->sched_scan_plans);
132 		wpa_s->sched_scan_plans = NULL;
133 		wpa_s->sched_scan_plans_num = 0;
134 	}
135 }
136 
137 
138 int autoscan_notify_scan(struct wpa_supplicant *wpa_s,
139 			 struct wpa_scan_results *scan_res)
140 {
141 	int interval;
142 
143 	if (wpa_s->autoscan && wpa_s->autoscan_priv) {
144 		interval = wpa_s->autoscan->notify_scan(wpa_s->autoscan_priv,
145 							scan_res);
146 
147 		if (interval <= 0)
148 			return -1;
149 
150 		wpa_s->scan_interval = interval;
151 		wpa_s->sched_scan_plans[0].interval = interval;
152 
153 		request_scan(wpa_s);
154 	}
155 
156 	return 0;
157 }
158