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 eloop_register_sock(fd, EVENT_TYPE_EXCEPTION, process_watch_exception,
112 priv, watch);
113
114 if (flags & DBUS_WATCH_READABLE) {
115 eloop_register_sock(fd, EVENT_TYPE_READ, process_watch_read,
116 priv, watch);
117 }
118 if (flags & DBUS_WATCH_WRITABLE) {
119 eloop_register_sock(fd, EVENT_TYPE_WRITE, process_watch_write,
120 priv, watch);
121 }
122
123 dbus_watch_set_data(watch, priv, NULL);
124
125 return TRUE;
126 }
127
128
remove_watch(DBusWatch * watch,void * data)129 static void remove_watch(DBusWatch *watch, void *data)
130 {
131 unsigned int flags;
132 int fd;
133
134 flags = dbus_watch_get_flags(watch);
135 fd = dbus_watch_get_unix_fd(watch);
136
137 eloop_unregister_sock(fd, EVENT_TYPE_EXCEPTION);
138
139 if (flags & DBUS_WATCH_READABLE)
140 eloop_unregister_sock(fd, EVENT_TYPE_READ);
141 if (flags & DBUS_WATCH_WRITABLE)
142 eloop_unregister_sock(fd, EVENT_TYPE_WRITE);
143
144 dbus_watch_set_data(watch, NULL, NULL);
145 }
146
147
watch_toggled(DBusWatch * watch,void * data)148 static void watch_toggled(DBusWatch *watch, void *data)
149 {
150 if (dbus_watch_get_enabled(watch))
151 add_watch(watch, data);
152 else
153 remove_watch(watch, data);
154 }
155
156
process_timeout(void * eloop_ctx,void * sock_ctx)157 static void process_timeout(void *eloop_ctx, void *sock_ctx)
158 {
159 DBusTimeout *timeout = sock_ctx;
160 dbus_timeout_handle(timeout);
161 }
162
163
add_timeout(DBusTimeout * timeout,void * data)164 static dbus_bool_t add_timeout(DBusTimeout *timeout, void *data)
165 {
166 struct wpas_dbus_priv *priv = data;
167
168 if (!dbus_timeout_get_enabled(timeout))
169 return TRUE;
170
171 eloop_register_timeout(0, dbus_timeout_get_interval(timeout) * 1000,
172 process_timeout, priv, timeout);
173
174 dbus_timeout_set_data(timeout, priv, NULL);
175
176 return TRUE;
177 }
178
179
remove_timeout(DBusTimeout * timeout,void * data)180 static void remove_timeout(DBusTimeout *timeout, void *data)
181 {
182 struct wpas_dbus_priv *priv = data;
183
184 eloop_cancel_timeout(process_timeout, priv, timeout);
185 dbus_timeout_set_data(timeout, NULL, NULL);
186 }
187
188
timeout_toggled(DBusTimeout * timeout,void * data)189 static void timeout_toggled(DBusTimeout *timeout, void *data)
190 {
191 if (dbus_timeout_get_enabled(timeout))
192 add_timeout(timeout, data);
193 else
194 remove_timeout(timeout, data);
195 }
196
197
process_wakeup_main(int sig,void * signal_ctx)198 static void process_wakeup_main(int sig, void *signal_ctx)
199 {
200 struct wpas_dbus_priv *priv = signal_ctx;
201
202 if (sig != SIGPOLL || !priv->con)
203 return;
204
205 if (dbus_connection_get_dispatch_status(priv->con) !=
206 DBUS_DISPATCH_DATA_REMAINS)
207 return;
208
209 /* Only dispatch once - we do not want to starve other events */
210 dbus_connection_ref(priv->con);
211 dbus_connection_dispatch(priv->con);
212 dbus_connection_unref(priv->con);
213 }
214
215
216 /**
217 * wakeup_main - Attempt to wake our mainloop up
218 * @data: dbus control interface private data
219 *
220 * Try to wake up the main eloop so it will process
221 * dbus events that may have happened.
222 */
wakeup_main(void * data)223 static void wakeup_main(void *data)
224 {
225 struct wpas_dbus_priv *priv = data;
226
227 /* Use SIGPOLL to break out of the eloop select() */
228 raise(SIGPOLL);
229 priv->should_dispatch = 1;
230 }
231
232
233 /**
234 * integrate_with_eloop - Register our mainloop integration with dbus
235 * @connection: connection to the system message bus
236 * @priv: a dbus control interface data structure
237 * Returns: 0 on success, -1 on failure
238 */
integrate_with_eloop(struct wpas_dbus_priv * priv)239 static int integrate_with_eloop(struct wpas_dbus_priv *priv)
240 {
241 if (!dbus_connection_set_watch_functions(priv->con, add_watch,
242 remove_watch, watch_toggled,
243 priv, NULL) ||
244 !dbus_connection_set_timeout_functions(priv->con, add_timeout,
245 remove_timeout,
246 timeout_toggled, priv,
247 NULL)) {
248 wpa_printf(MSG_ERROR, "dbus: Failed to set callback functions");
249 return -1;
250 }
251
252 if (eloop_register_signal(SIGPOLL, process_wakeup_main, priv))
253 return -1;
254 dbus_connection_set_wakeup_main_function(priv->con, wakeup_main,
255 priv, NULL);
256
257 return 0;
258 }
259
260
disconnect_filter(DBusConnection * conn,DBusMessage * message,void * data)261 static DBusHandlerResult disconnect_filter(DBusConnection *conn,
262 DBusMessage *message, void *data)
263 {
264 struct wpas_dbus_priv *priv = data;
265
266 if (dbus_message_is_signal(message, DBUS_INTERFACE_LOCAL,
267 "Disconnected")) {
268 wpa_printf(MSG_DEBUG, "dbus: bus disconnected, terminating");
269 dbus_connection_set_exit_on_disconnect(conn, FALSE);
270 wpa_supplicant_terminate_proc(priv->global);
271 return DBUS_HANDLER_RESULT_HANDLED;
272 } else
273 return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
274 }
275
276
wpas_dbus_init_common(struct wpas_dbus_priv * priv)277 static int wpas_dbus_init_common(struct wpas_dbus_priv *priv)
278 {
279 DBusError error;
280 int ret = 0;
281
282 /* Get a reference to the system bus */
283 dbus_error_init(&error);
284 priv->con = dbus_bus_get(DBUS_BUS_SYSTEM, &error);
285 if (priv->con) {
286 dbus_connection_add_filter(priv->con, disconnect_filter, priv,
287 NULL);
288 } else {
289 wpa_printf(MSG_ERROR,
290 "dbus: Could not acquire the system bus: %s - %s",
291 error.name, error.message);
292 ret = -1;
293 }
294 dbus_error_free(&error);
295
296 return ret;
297 }
298
299
wpas_dbus_init_common_finish(struct wpas_dbus_priv * priv)300 static int wpas_dbus_init_common_finish(struct wpas_dbus_priv *priv)
301 {
302 /* Tell dbus about our mainloop integration functions */
303 integrate_with_eloop(priv);
304
305 /*
306 * Dispatch initial DBus messages that may have come in since the bus
307 * name was claimed above. Happens when clients are quick to notice the
308 * service.
309 *
310 * FIXME: is there a better solution to this problem?
311 */
312 eloop_register_timeout(0, 50, dispatch_initial_dbus_messages,
313 priv->con, NULL);
314
315 return 0;
316 }
317
318
wpas_dbus_deinit_common(struct wpas_dbus_priv * priv)319 static void wpas_dbus_deinit_common(struct wpas_dbus_priv *priv)
320 {
321 if (priv->con) {
322 eloop_cancel_timeout(dispatch_initial_dbus_messages,
323 priv->con, NULL);
324 eloop_cancel_timeout(process_timeout, priv, ELOOP_ALL_CTX);
325
326 dbus_connection_set_watch_functions(priv->con, NULL, NULL,
327 NULL, NULL, NULL);
328 dbus_connection_set_timeout_functions(priv->con, NULL, NULL,
329 NULL, NULL, NULL);
330 dbus_connection_remove_filter(priv->con, disconnect_filter,
331 priv);
332
333 dbus_connection_unref(priv->con);
334 }
335
336 os_free(priv);
337 }
338
339
wpas_dbus_init(struct wpa_global * global)340 struct wpas_dbus_priv * wpas_dbus_init(struct wpa_global *global)
341 {
342 struct wpas_dbus_priv *priv;
343
344 priv = os_zalloc(sizeof(*priv));
345 if (priv == NULL)
346 return NULL;
347 priv->global = global;
348
349 if (wpas_dbus_init_common(priv) < 0 ||
350 #ifdef CONFIG_CTRL_IFACE_DBUS_NEW
351 wpas_dbus_ctrl_iface_init(priv) < 0 ||
352 #endif /* CONFIG_CTRL_IFACE_DBUS_NEW */
353 wpas_dbus_init_common_finish(priv) < 0) {
354 wpas_dbus_deinit(priv);
355 return NULL;
356 }
357
358 return priv;
359 }
360
361
wpas_dbus_deinit(struct wpas_dbus_priv * priv)362 void wpas_dbus_deinit(struct wpas_dbus_priv *priv)
363 {
364 if (priv == NULL)
365 return;
366
367 #ifdef CONFIG_CTRL_IFACE_DBUS_NEW
368 wpas_dbus_ctrl_iface_deinit(priv);
369 #endif /* CONFIG_CTRL_IFACE_DBUS_NEW */
370
371 wpas_dbus_deinit_common(priv);
372 }
373