1 /*
2 * wpa_supplicant D-Bus control interface - common functionality
3 * Copyright (c) 2006, Dan Williams <dcbw@redhat.com> and Red Hat, Inc.
4 * Copyright (c) 2009, Witold Sowa <witold.sowa@gmail.com>
5 * Copyright (c) 2009, Jouni Malinen <j@w1.fi>
6 *
7 * This software may be distributed under the terms of the BSD license.
8 * See README for more details.
9 */
10
11 #include "utils/includes.h"
12 #include <dbus/dbus.h>
13
14 #include "utils/common.h"
15 #include "utils/eloop.h"
16 #include "dbus_common.h"
17 #include "dbus_common_i.h"
18 #include "dbus_new.h"
19 #include "../wpa_supplicant_i.h"
20
21
22 #ifndef SIGPOLL
23 #ifdef SIGIO
24 /*
25 * If we do not have SIGPOLL, try to use SIGIO instead. This is needed for
26 * FreeBSD.
27 */
28 #define SIGPOLL SIGIO
29 #endif
30 #endif
31
32
dispatch_data(DBusConnection * con)33 static void dispatch_data(DBusConnection *con)
34 {
35 while (dbus_connection_get_dispatch_status(con) ==
36 DBUS_DISPATCH_DATA_REMAINS)
37 dbus_connection_dispatch(con);
38 }
39
40
41 /**
42 * dispatch_initial_dbus_messages - Dispatch initial dbus messages after
43 * claiming bus name
44 * @eloop_ctx: the DBusConnection to dispatch on
45 * @timeout_ctx: unused
46 *
47 * If clients are quick to notice that service claimed its bus name,
48 * there may have been messages that came in before initialization was
49 * all finished. Dispatch those here.
50 */
dispatch_initial_dbus_messages(void * eloop_ctx,void * timeout_ctx)51 static void dispatch_initial_dbus_messages(void *eloop_ctx, void *timeout_ctx)
52 {
53 DBusConnection *con = eloop_ctx;
54 dispatch_data(con);
55 }
56
57
process_watch(struct wpas_dbus_priv * priv,DBusWatch * watch,eloop_event_type type)58 static void process_watch(struct wpas_dbus_priv *priv,
59 DBusWatch *watch, eloop_event_type type)
60 {
61 dbus_connection_ref(priv->con);
62
63 priv->should_dispatch = 0;
64
65 if (type == EVENT_TYPE_READ)
66 dbus_watch_handle(watch, DBUS_WATCH_READABLE);
67 else if (type == EVENT_TYPE_WRITE)
68 dbus_watch_handle(watch, DBUS_WATCH_WRITABLE);
69 else if (type == EVENT_TYPE_EXCEPTION)
70 dbus_watch_handle(watch, DBUS_WATCH_ERROR);
71
72 if (priv->should_dispatch) {
73 dispatch_data(priv->con);
74 priv->should_dispatch = 0;
75 }
76
77 dbus_connection_unref(priv->con);
78 }
79
80
process_watch_exception(int sock,void * eloop_ctx,void * sock_ctx)81 static void process_watch_exception(int sock, void *eloop_ctx, void *sock_ctx)
82 {
83 process_watch(eloop_ctx, sock_ctx, EVENT_TYPE_EXCEPTION);
84 }
85
86
process_watch_read(int sock,void * eloop_ctx,void * sock_ctx)87 static void process_watch_read(int sock, void *eloop_ctx, void *sock_ctx)
88 {
89 process_watch(eloop_ctx, sock_ctx, EVENT_TYPE_READ);
90 }
91
92
process_watch_write(int sock,void * eloop_ctx,void * sock_ctx)93 static void process_watch_write(int sock, void *eloop_ctx, void *sock_ctx)
94 {
95 process_watch(eloop_ctx, sock_ctx, EVENT_TYPE_WRITE);
96 }
97
98
add_watch(DBusWatch * watch,void * data)99 static dbus_bool_t add_watch(DBusWatch *watch, void *data)
100 {
101 struct wpas_dbus_priv *priv = data;
102 unsigned int flags;
103 int fd;
104
105 if (!dbus_watch_get_enabled(watch))
106 return TRUE;
107
108 flags = dbus_watch_get_flags(watch);
109 fd = dbus_watch_get_unix_fd(watch);
110
111 if (eloop_register_sock(fd, EVENT_TYPE_EXCEPTION,
112 process_watch_exception, priv, watch) < 0)
113 return FALSE;
114
115 if ((flags & DBUS_WATCH_READABLE) &&
116 eloop_register_sock(fd, EVENT_TYPE_READ, process_watch_read,
117 priv, watch) < 0)
118 return FALSE;
119 if ((flags & DBUS_WATCH_WRITABLE) &&
120 eloop_register_sock(fd, EVENT_TYPE_WRITE, process_watch_write,
121 priv, watch) < 0)
122 return FALSE;
123
124 dbus_watch_set_data(watch, priv, NULL);
125
126 return TRUE;
127 }
128
129
remove_watch(DBusWatch * watch,void * data)130 static void remove_watch(DBusWatch *watch, void *data)
131 {
132 unsigned int flags;
133 int fd;
134
135 flags = dbus_watch_get_flags(watch);
136 fd = dbus_watch_get_unix_fd(watch);
137
138 eloop_unregister_sock(fd, EVENT_TYPE_EXCEPTION);
139
140 if (flags & DBUS_WATCH_READABLE)
141 eloop_unregister_sock(fd, EVENT_TYPE_READ);
142 if (flags & DBUS_WATCH_WRITABLE)
143 eloop_unregister_sock(fd, EVENT_TYPE_WRITE);
144
145 dbus_watch_set_data(watch, NULL, NULL);
146 }
147
148
watch_toggled(DBusWatch * watch,void * data)149 static void watch_toggled(DBusWatch *watch, void *data)
150 {
151 if (dbus_watch_get_enabled(watch))
152 add_watch(watch, data);
153 else
154 remove_watch(watch, data);
155 }
156
157
process_timeout(void * eloop_ctx,void * sock_ctx)158 static void process_timeout(void *eloop_ctx, void *sock_ctx)
159 {
160 DBusTimeout *timeout = sock_ctx;
161 dbus_timeout_handle(timeout);
162 }
163
164
add_timeout(DBusTimeout * timeout,void * data)165 static dbus_bool_t add_timeout(DBusTimeout *timeout, void *data)
166 {
167 struct wpas_dbus_priv *priv = data;
168
169 if (!dbus_timeout_get_enabled(timeout))
170 return TRUE;
171
172 eloop_register_timeout(0, dbus_timeout_get_interval(timeout) * 1000,
173 process_timeout, priv, timeout);
174
175 dbus_timeout_set_data(timeout, priv, NULL);
176
177 return TRUE;
178 }
179
180
remove_timeout(DBusTimeout * timeout,void * data)181 static void remove_timeout(DBusTimeout *timeout, void *data)
182 {
183 struct wpas_dbus_priv *priv = data;
184
185 eloop_cancel_timeout(process_timeout, priv, timeout);
186 dbus_timeout_set_data(timeout, NULL, NULL);
187 }
188
189
timeout_toggled(DBusTimeout * timeout,void * data)190 static void timeout_toggled(DBusTimeout *timeout, void *data)
191 {
192 if (dbus_timeout_get_enabled(timeout))
193 add_timeout(timeout, data);
194 else
195 remove_timeout(timeout, data);
196 }
197
198
process_wakeup_main(int sig,void * signal_ctx)199 static void process_wakeup_main(int sig, void *signal_ctx)
200 {
201 struct wpas_dbus_priv *priv = signal_ctx;
202
203 if (sig != SIGPOLL || !priv->con)
204 return;
205
206 if (dbus_connection_get_dispatch_status(priv->con) !=
207 DBUS_DISPATCH_DATA_REMAINS)
208 return;
209
210 /* Only dispatch once - we do not want to starve other events */
211 dbus_connection_ref(priv->con);
212 dbus_connection_dispatch(priv->con);
213 dbus_connection_unref(priv->con);
214 }
215
216
217 /**
218 * wakeup_main - Attempt to wake our mainloop up
219 * @data: dbus control interface private data
220 *
221 * Try to wake up the main eloop so it will process
222 * dbus events that may have happened.
223 */
wakeup_main(void * data)224 static void wakeup_main(void *data)
225 {
226 struct wpas_dbus_priv *priv = data;
227
228 /* Use SIGPOLL to break out of the eloop select() */
229 raise(SIGPOLL);
230 priv->should_dispatch = 1;
231 }
232
233
234 /**
235 * integrate_with_eloop - Register our mainloop integration with dbus
236 * @connection: connection to the system message bus
237 * @priv: a dbus control interface data structure
238 * Returns: 0 on success, -1 on failure
239 */
integrate_with_eloop(struct wpas_dbus_priv * priv)240 static int integrate_with_eloop(struct wpas_dbus_priv *priv)
241 {
242 if (!dbus_connection_set_watch_functions(priv->con, add_watch,
243 remove_watch, watch_toggled,
244 priv, NULL) ||
245 !dbus_connection_set_timeout_functions(priv->con, add_timeout,
246 remove_timeout,
247 timeout_toggled, priv,
248 NULL)) {
249 wpa_printf(MSG_ERROR, "dbus: Failed to set callback functions");
250 return -1;
251 }
252
253 if (eloop_register_signal(SIGPOLL, process_wakeup_main, priv))
254 return -1;
255 dbus_connection_set_wakeup_main_function(priv->con, wakeup_main,
256 priv, NULL);
257
258 return 0;
259 }
260
261
disconnect_filter(DBusConnection * conn,DBusMessage * message,void * data)262 static DBusHandlerResult disconnect_filter(DBusConnection *conn,
263 DBusMessage *message, void *data)
264 {
265 struct wpas_dbus_priv *priv = data;
266
267 if (dbus_message_is_signal(message, DBUS_INTERFACE_LOCAL,
268 "Disconnected")) {
269 wpa_printf(MSG_DEBUG, "dbus: bus disconnected, terminating");
270 dbus_connection_set_exit_on_disconnect(conn, FALSE);
271 wpa_supplicant_terminate_proc(priv->global);
272 return DBUS_HANDLER_RESULT_HANDLED;
273 } else
274 return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
275 }
276
277
wpas_dbus_init_common(struct wpas_dbus_priv * priv)278 static int wpas_dbus_init_common(struct wpas_dbus_priv *priv)
279 {
280 DBusError error;
281 int ret = 0;
282
283 /* Get a reference to the system bus */
284 dbus_error_init(&error);
285 priv->con = dbus_bus_get(DBUS_BUS_SYSTEM, &error);
286 if (priv->con) {
287 dbus_connection_add_filter(priv->con, disconnect_filter, priv,
288 NULL);
289 } else {
290 wpa_printf(MSG_ERROR,
291 "dbus: Could not acquire the system bus: %s - %s",
292 error.name, error.message);
293 ret = -1;
294 }
295 dbus_error_free(&error);
296
297 return ret;
298 }
299
300
wpas_dbus_init_common_finish(struct wpas_dbus_priv * priv)301 static int wpas_dbus_init_common_finish(struct wpas_dbus_priv *priv)
302 {
303 /* Tell dbus about our mainloop integration functions */
304 integrate_with_eloop(priv);
305
306 /*
307 * Dispatch initial DBus messages that may have come in since the bus
308 * name was claimed above. Happens when clients are quick to notice the
309 * service.
310 *
311 * FIXME: is there a better solution to this problem?
312 */
313 eloop_register_timeout(0, 50, dispatch_initial_dbus_messages,
314 priv->con, NULL);
315
316 return 0;
317 }
318
319
wpas_dbus_deinit_common(struct wpas_dbus_priv * priv)320 static void wpas_dbus_deinit_common(struct wpas_dbus_priv *priv)
321 {
322 if (priv->con) {
323 eloop_cancel_timeout(dispatch_initial_dbus_messages,
324 priv->con, NULL);
325 eloop_cancel_timeout(process_timeout, priv, ELOOP_ALL_CTX);
326
327 dbus_connection_set_watch_functions(priv->con, NULL, NULL,
328 NULL, NULL, NULL);
329 dbus_connection_set_timeout_functions(priv->con, NULL, NULL,
330 NULL, NULL, NULL);
331 dbus_connection_remove_filter(priv->con, disconnect_filter,
332 priv);
333
334 dbus_connection_unref(priv->con);
335 }
336
337 os_free(priv);
338 }
339
340
wpas_dbus_init(struct wpa_global * global)341 struct wpas_dbus_priv * wpas_dbus_init(struct wpa_global *global)
342 {
343 struct wpas_dbus_priv *priv;
344
345 priv = os_zalloc(sizeof(*priv));
346 if (priv == NULL)
347 return NULL;
348 priv->global = global;
349
350 if (wpas_dbus_init_common(priv) < 0 ||
351 #ifdef CONFIG_CTRL_IFACE_DBUS_NEW
352 wpas_dbus_ctrl_iface_init(priv) < 0 ||
353 #endif /* CONFIG_CTRL_IFACE_DBUS_NEW */
354 wpas_dbus_init_common_finish(priv) < 0) {
355 wpas_dbus_deinit(priv);
356 return NULL;
357 }
358
359 return priv;
360 }
361
362
wpas_dbus_deinit(struct wpas_dbus_priv * priv)363 void wpas_dbus_deinit(struct wpas_dbus_priv *priv)
364 {
365 if (priv == NULL)
366 return;
367
368 #ifdef CONFIG_CTRL_IFACE_DBUS_NEW
369 wpas_dbus_ctrl_iface_deinit(priv);
370 #endif /* CONFIG_CTRL_IFACE_DBUS_NEW */
371
372 wpas_dbus_deinit_common(priv);
373 }
374