1 /*
2  * WPA Supplicant / UNIX domain socket -based control interface
3  * Copyright (c) 2004-2014, Jouni Malinen <j@w1.fi>
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 #include <sys/un.h>
11 #include <sys/stat.h>
12 #include <grp.h>
13 #include <stddef.h>
14 #include <unistd.h>
15 #include <fcntl.h>
16 #ifdef ANDROID
17 #include <cutils/sockets.h>
18 #endif /* ANDROID */
19 
20 #include "utils/common.h"
21 #include "utils/eloop.h"
22 #include "utils/list.h"
23 #include "eapol_supp/eapol_supp_sm.h"
24 #include "config.h"
25 #include "wpa_supplicant_i.h"
26 #include "ctrl_iface.h"
27 
28 /* Per-interface ctrl_iface */
29 
30 /**
31  * struct wpa_ctrl_dst - Internal data structure of control interface monitors
32  *
33  * This structure is used to store information about registered control
34  * interface monitors into struct wpa_supplicant. This data is private to
35  * ctrl_iface_unix.c and should not be touched directly from other files.
36  */
37 struct wpa_ctrl_dst {
38 	struct dl_list list;
39 	struct sockaddr_un addr;
40 	socklen_t addrlen;
41 	int debug_level;
42 	int errors;
43 };
44 
45 
46 struct ctrl_iface_priv {
47 	struct wpa_supplicant *wpa_s;
48 	int sock;
49 	struct dl_list ctrl_dst;
50 };
51 
52 
53 struct ctrl_iface_global_priv {
54 	struct wpa_global *global;
55 	int sock;
56 	struct dl_list ctrl_dst;
57 };
58 
59 
60 static void wpa_supplicant_ctrl_iface_send(struct wpa_supplicant *wpa_s,
61 					   const char *ifname, int sock,
62 					   struct dl_list *ctrl_dst,
63 					   int level, const char *buf,
64 					   size_t len,
65 					   struct ctrl_iface_priv *priv,
66 					   struct ctrl_iface_global_priv *gp);
67 static int wpas_ctrl_iface_reinit(struct wpa_supplicant *wpa_s,
68 				  struct ctrl_iface_priv *priv);
69 static int wpas_ctrl_iface_global_reinit(struct wpa_global *global,
70 					 struct ctrl_iface_global_priv *priv);
71 
72 
73 static int wpa_supplicant_ctrl_iface_attach(struct dl_list *ctrl_dst,
74 					    struct sockaddr_un *from,
75 					    socklen_t fromlen)
76 {
77 	struct wpa_ctrl_dst *dst;
78 	char addr_txt[200];
79 
80 	dst = os_zalloc(sizeof(*dst));
81 	if (dst == NULL)
82 		return -1;
83 	os_memcpy(&dst->addr, from, sizeof(struct sockaddr_un));
84 	dst->addrlen = fromlen;
85 	dst->debug_level = MSG_INFO;
86 	dl_list_add(ctrl_dst, &dst->list);
87 	printf_encode(addr_txt, sizeof(addr_txt),
88 		      (u8 *) from->sun_path,
89 		      fromlen - offsetof(struct sockaddr_un, sun_path));
90 	wpa_printf(MSG_DEBUG, "CTRL_IFACE monitor attached %s", addr_txt);
91 	return 0;
92 }
93 
94 
95 static int wpa_supplicant_ctrl_iface_detach(struct dl_list *ctrl_dst,
96 					    struct sockaddr_un *from,
97 					    socklen_t fromlen)
98 {
99 	struct wpa_ctrl_dst *dst;
100 
101 	dl_list_for_each(dst, ctrl_dst, struct wpa_ctrl_dst, list) {
102 		if (fromlen == dst->addrlen &&
103 		    os_memcmp(from->sun_path, dst->addr.sun_path,
104 			      fromlen - offsetof(struct sockaddr_un, sun_path))
105 		    == 0) {
106 			char addr_txt[200];
107 			printf_encode(addr_txt, sizeof(addr_txt),
108 				      (u8 *) from->sun_path,
109 				      fromlen -
110 				      offsetof(struct sockaddr_un, sun_path));
111 			wpa_printf(MSG_DEBUG, "CTRL_IFACE monitor detached %s",
112 				   addr_txt);
113 			dl_list_del(&dst->list);
114 			os_free(dst);
115 			return 0;
116 		}
117 	}
118 	return -1;
119 }
120 
121 
122 static int wpa_supplicant_ctrl_iface_level(struct ctrl_iface_priv *priv,
123 					   struct sockaddr_un *from,
124 					   socklen_t fromlen,
125 					   char *level)
126 {
127 	struct wpa_ctrl_dst *dst;
128 
129 	wpa_printf(MSG_DEBUG, "CTRL_IFACE LEVEL %s", level);
130 
131 	dl_list_for_each(dst, &priv->ctrl_dst, struct wpa_ctrl_dst, list) {
132 		if (fromlen == dst->addrlen &&
133 		    os_memcmp(from->sun_path, dst->addr.sun_path,
134 			      fromlen - offsetof(struct sockaddr_un, sun_path))
135 		    == 0) {
136 			char addr_txt[200];
137 			dst->debug_level = atoi(level);
138 			printf_encode(addr_txt, sizeof(addr_txt),
139 				      (u8 *) from->sun_path, fromlen -
140 				      offsetof(struct sockaddr_un, sun_path));
141 			wpa_printf(MSG_DEBUG, "CTRL_IFACE changed monitor level to %d for %s",
142 				   dst->debug_level, addr_txt);
143 			return 0;
144 		}
145 	}
146 
147 	return -1;
148 }
149 
150 
151 static void wpa_supplicant_ctrl_iface_receive(int sock, void *eloop_ctx,
152 					      void *sock_ctx)
153 {
154 	struct wpa_supplicant *wpa_s = eloop_ctx;
155 	struct ctrl_iface_priv *priv = sock_ctx;
156 	char buf[4096];
157 	int res;
158 	struct sockaddr_un from;
159 	socklen_t fromlen = sizeof(from);
160 	char *reply = NULL, *reply_buf = NULL;
161 	size_t reply_len = 0;
162 	int new_attached = 0;
163 
164 	res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
165 		       (struct sockaddr *) &from, &fromlen);
166 	if (res < 0) {
167 		wpa_printf(MSG_ERROR, "recvfrom(ctrl_iface): %s",
168 			   strerror(errno));
169 		return;
170 	}
171 	buf[res] = '\0';
172 
173 	if (os_strcmp(buf, "ATTACH") == 0) {
174 		if (wpa_supplicant_ctrl_iface_attach(&priv->ctrl_dst, &from,
175 						     fromlen))
176 			reply_len = 1;
177 		else {
178 			new_attached = 1;
179 			reply_len = 2;
180 		}
181 	} else if (os_strcmp(buf, "DETACH") == 0) {
182 		if (wpa_supplicant_ctrl_iface_detach(&priv->ctrl_dst, &from,
183 						     fromlen))
184 			reply_len = 1;
185 		else
186 			reply_len = 2;
187 	} else if (os_strncmp(buf, "LEVEL ", 6) == 0) {
188 		if (wpa_supplicant_ctrl_iface_level(priv, &from, fromlen,
189 						    buf + 6))
190 			reply_len = 1;
191 		else
192 			reply_len = 2;
193 	} else {
194 		reply_buf = wpa_supplicant_ctrl_iface_process(wpa_s, buf,
195 							      &reply_len);
196 		reply = reply_buf;
197 	}
198 
199 	if (!reply && reply_len == 1) {
200 		reply = "FAIL\n";
201 		reply_len = 5;
202 	} else if (!reply && reply_len == 2) {
203 		reply = "OK\n";
204 		reply_len = 3;
205 	}
206 
207 	if (reply) {
208 		if (sendto(sock, reply, reply_len, 0, (struct sockaddr *) &from,
209 			   fromlen) < 0) {
210 			int _errno = errno;
211 			wpa_dbg(wpa_s, MSG_DEBUG,
212 				"ctrl_iface sendto failed: %d - %s",
213 				_errno, strerror(_errno));
214 			if (_errno == ENOBUFS || _errno == EAGAIN) {
215 				/*
216 				 * The socket send buffer could be full. This
217 				 * may happen if client programs are not
218 				 * receiving their pending messages. Close and
219 				 * reopen the socket as a workaround to avoid
220 				 * getting stuck being unable to send any new
221 				 * responses.
222 				 */
223 				sock = wpas_ctrl_iface_reinit(wpa_s, priv);
224 				if (sock < 0) {
225 					wpa_dbg(wpa_s, MSG_DEBUG, "Failed to reinitialize ctrl_iface socket");
226 				}
227 			}
228 			if (new_attached) {
229 				wpa_dbg(wpa_s, MSG_DEBUG, "Failed to send response to ATTACH - detaching");
230 				new_attached = 0;
231 				wpa_supplicant_ctrl_iface_detach(
232 					&priv->ctrl_dst, &from, fromlen);
233 			}
234 		}
235 	}
236 	os_free(reply_buf);
237 
238 	if (new_attached)
239 		eapol_sm_notify_ctrl_attached(wpa_s->eapol);
240 }
241 
242 
243 static char * wpa_supplicant_ctrl_iface_path(struct wpa_supplicant *wpa_s)
244 {
245 	char *buf;
246 	size_t len;
247 	char *pbuf, *dir = NULL, *gid_str = NULL;
248 	int res;
249 
250 	if (wpa_s->conf->ctrl_interface == NULL)
251 		return NULL;
252 
253 	pbuf = os_strdup(wpa_s->conf->ctrl_interface);
254 	if (pbuf == NULL)
255 		return NULL;
256 	if (os_strncmp(pbuf, "DIR=", 4) == 0) {
257 		dir = pbuf + 4;
258 		gid_str = os_strstr(dir, " GROUP=");
259 		if (gid_str) {
260 			*gid_str = '\0';
261 			gid_str += 7;
262 		}
263 	} else
264 		dir = pbuf;
265 
266 	len = os_strlen(dir) + os_strlen(wpa_s->ifname) + 2;
267 	buf = os_malloc(len);
268 	if (buf == NULL) {
269 		os_free(pbuf);
270 		return NULL;
271 	}
272 
273 	res = os_snprintf(buf, len, "%s/%s", dir, wpa_s->ifname);
274 	if (res < 0 || (size_t) res >= len) {
275 		os_free(pbuf);
276 		os_free(buf);
277 		return NULL;
278 	}
279 #ifdef __CYGWIN__
280 	{
281 		/* Windows/WinPcap uses interface names that are not suitable
282 		 * as a file name - convert invalid chars to underscores */
283 		char *pos = buf;
284 		while (*pos) {
285 			if (*pos == '\\')
286 				*pos = '_';
287 			pos++;
288 		}
289 	}
290 #endif /* __CYGWIN__ */
291 	os_free(pbuf);
292 	return buf;
293 }
294 
295 
296 static void wpa_supplicant_ctrl_iface_msg_cb(void *ctx, int level, int global,
297 					     const char *txt, size_t len)
298 {
299 	struct wpa_supplicant *wpa_s = ctx;
300 
301 	if (wpa_s == NULL)
302 		return;
303 
304 	if (global != 2 && wpa_s->global->ctrl_iface) {
305 		struct ctrl_iface_global_priv *priv = wpa_s->global->ctrl_iface;
306 		if (!dl_list_empty(&priv->ctrl_dst)) {
307 			wpa_supplicant_ctrl_iface_send(wpa_s, global ? NULL :
308 						       wpa_s->ifname,
309 						       priv->sock,
310 						       &priv->ctrl_dst,
311 						       level, txt, len, NULL,
312 						       priv);
313 		}
314 	}
315 
316 	if (wpa_s->ctrl_iface == NULL)
317 		return;
318 	wpa_supplicant_ctrl_iface_send(wpa_s, NULL, wpa_s->ctrl_iface->sock,
319 				       &wpa_s->ctrl_iface->ctrl_dst,
320 				       level, txt, len, wpa_s->ctrl_iface,
321 				       NULL);
322 }
323 
324 
325 static int wpas_ctrl_iface_open_sock(struct wpa_supplicant *wpa_s,
326 				     struct ctrl_iface_priv *priv)
327 {
328 	struct sockaddr_un addr;
329 	char *fname = NULL;
330 	gid_t gid = 0;
331 	int gid_set = 0;
332 	char *buf, *dir = NULL, *gid_str = NULL;
333 	struct group *grp;
334 	char *endp;
335 	int flags;
336 
337 	buf = os_strdup(wpa_s->conf->ctrl_interface);
338 	if (buf == NULL)
339 		goto fail;
340 #ifdef ANDROID
341 	os_snprintf(addr.sun_path, sizeof(addr.sun_path), "wpa_%s",
342 		    wpa_s->conf->ctrl_interface);
343 	priv->sock = android_get_control_socket(addr.sun_path);
344 	if (priv->sock >= 0)
345 		goto havesock;
346 #endif /* ANDROID */
347 	if (os_strncmp(buf, "DIR=", 4) == 0) {
348 		dir = buf + 4;
349 		gid_str = os_strstr(dir, " GROUP=");
350 		if (gid_str) {
351 			*gid_str = '\0';
352 			gid_str += 7;
353 		}
354 	} else {
355 		dir = buf;
356 		gid_str = wpa_s->conf->ctrl_interface_group;
357 	}
358 
359 	if (mkdir(dir, S_IRWXU | S_IRWXG) < 0) {
360 		if (errno == EEXIST) {
361 			wpa_printf(MSG_DEBUG, "Using existing control "
362 				   "interface directory.");
363 		} else {
364 			wpa_printf(MSG_ERROR, "mkdir[ctrl_interface=%s]: %s",
365 				   dir, strerror(errno));
366 			goto fail;
367 		}
368 	}
369 
370 #ifdef ANDROID
371 	/*
372 	 * wpa_supplicant is started from /init.*.rc on Android and that seems
373 	 * to be using umask 0077 which would leave the control interface
374 	 * directory without group access. This breaks things since Wi-Fi
375 	 * framework assumes that this directory can be accessed by other
376 	 * applications in the wifi group. Fix this by adding group access even
377 	 * if umask value would prevent this.
378 	 */
379 	if (chmod(dir, S_IRWXU | S_IRWXG) < 0) {
380 		wpa_printf(MSG_ERROR, "CTRL: Could not chmod directory: %s",
381 			   strerror(errno));
382 		/* Try to continue anyway */
383 	}
384 #endif /* ANDROID */
385 
386 	if (gid_str) {
387 		grp = getgrnam(gid_str);
388 		if (grp) {
389 			gid = grp->gr_gid;
390 			gid_set = 1;
391 			wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d"
392 				   " (from group name '%s')",
393 				   (int) gid, gid_str);
394 		} else {
395 			/* Group name not found - try to parse this as gid */
396 			gid = strtol(gid_str, &endp, 10);
397 			if (*gid_str == '\0' || *endp != '\0') {
398 				wpa_printf(MSG_ERROR, "CTRL: Invalid group "
399 					   "'%s'", gid_str);
400 				goto fail;
401 			}
402 			gid_set = 1;
403 			wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d",
404 				   (int) gid);
405 		}
406 	}
407 
408 	if (gid_set && chown(dir, -1, gid) < 0) {
409 		wpa_printf(MSG_ERROR, "chown[ctrl_interface=%s,gid=%d]: %s",
410 			   dir, (int) gid, strerror(errno));
411 		goto fail;
412 	}
413 
414 	/* Make sure the group can enter and read the directory */
415 	if (gid_set &&
416 	    chmod(dir, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IXGRP) < 0) {
417 		wpa_printf(MSG_ERROR, "CTRL: chmod[ctrl_interface]: %s",
418 			   strerror(errno));
419 		goto fail;
420 	}
421 
422 	if (os_strlen(dir) + 1 + os_strlen(wpa_s->ifname) >=
423 	    sizeof(addr.sun_path)) {
424 		wpa_printf(MSG_ERROR, "ctrl_iface path limit exceeded");
425 		goto fail;
426 	}
427 
428 	priv->sock = socket(PF_UNIX, SOCK_DGRAM, 0);
429 	if (priv->sock < 0) {
430 		wpa_printf(MSG_ERROR, "socket(PF_UNIX): %s", strerror(errno));
431 		goto fail;
432 	}
433 
434 	os_memset(&addr, 0, sizeof(addr));
435 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
436 	addr.sun_len = sizeof(addr);
437 #endif /* __FreeBSD__ */
438 	addr.sun_family = AF_UNIX;
439 	fname = wpa_supplicant_ctrl_iface_path(wpa_s);
440 	if (fname == NULL)
441 		goto fail;
442 	os_strlcpy(addr.sun_path, fname, sizeof(addr.sun_path));
443 	if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
444 		wpa_printf(MSG_DEBUG, "ctrl_iface bind(PF_UNIX) failed: %s",
445 			   strerror(errno));
446 		if (connect(priv->sock, (struct sockaddr *) &addr,
447 			    sizeof(addr)) < 0) {
448 			wpa_printf(MSG_DEBUG, "ctrl_iface exists, but does not"
449 				   " allow connections - assuming it was left"
450 				   "over from forced program termination");
451 			if (unlink(fname) < 0) {
452 				wpa_printf(MSG_ERROR,
453 					   "Could not unlink existing ctrl_iface socket '%s': %s",
454 					   fname, strerror(errno));
455 				goto fail;
456 			}
457 			if (bind(priv->sock, (struct sockaddr *) &addr,
458 				 sizeof(addr)) < 0) {
459 				wpa_printf(MSG_ERROR, "supp-ctrl-iface-init: bind(PF_UNIX): %s",
460 					   strerror(errno));
461 				goto fail;
462 			}
463 			wpa_printf(MSG_DEBUG, "Successfully replaced leftover "
464 				   "ctrl_iface socket '%s'", fname);
465 		} else {
466 			wpa_printf(MSG_INFO, "ctrl_iface exists and seems to "
467 				   "be in use - cannot override it");
468 			wpa_printf(MSG_INFO, "Delete '%s' manually if it is "
469 				   "not used anymore", fname);
470 			os_free(fname);
471 			fname = NULL;
472 			goto fail;
473 		}
474 	}
475 
476 	if (gid_set && chown(fname, -1, gid) < 0) {
477 		wpa_printf(MSG_ERROR, "chown[ctrl_interface=%s,gid=%d]: %s",
478 			   fname, (int) gid, strerror(errno));
479 		goto fail;
480 	}
481 
482 	if (chmod(fname, S_IRWXU | S_IRWXG) < 0) {
483 		wpa_printf(MSG_ERROR, "chmod[ctrl_interface=%s]: %s",
484 			   fname, strerror(errno));
485 		goto fail;
486 	}
487 	os_free(fname);
488 
489 #ifdef ANDROID
490 havesock:
491 #endif /* ANDROID */
492 
493 	/*
494 	 * Make socket non-blocking so that we don't hang forever if
495 	 * target dies unexpectedly.
496 	 */
497 	flags = fcntl(priv->sock, F_GETFL);
498 	if (flags >= 0) {
499 		flags |= O_NONBLOCK;
500 		if (fcntl(priv->sock, F_SETFL, flags) < 0) {
501 			wpa_printf(MSG_INFO, "fcntl(ctrl, O_NONBLOCK): %s",
502 				   strerror(errno));
503 			/* Not fatal, continue on.*/
504 		}
505 	}
506 
507 	eloop_register_read_sock(priv->sock, wpa_supplicant_ctrl_iface_receive,
508 				 wpa_s, priv);
509 	wpa_msg_register_cb(wpa_supplicant_ctrl_iface_msg_cb);
510 
511 	os_free(buf);
512 	return 0;
513 
514 fail:
515 	if (priv->sock >= 0) {
516 		close(priv->sock);
517 		priv->sock = -1;
518 	}
519 	if (fname) {
520 		unlink(fname);
521 		os_free(fname);
522 	}
523 	os_free(buf);
524 	return -1;
525 }
526 
527 
528 struct ctrl_iface_priv *
529 wpa_supplicant_ctrl_iface_init(struct wpa_supplicant *wpa_s)
530 {
531 	struct ctrl_iface_priv *priv;
532 
533 	priv = os_zalloc(sizeof(*priv));
534 	if (priv == NULL)
535 		return NULL;
536 	dl_list_init(&priv->ctrl_dst);
537 	priv->wpa_s = wpa_s;
538 	priv->sock = -1;
539 
540 	if (wpa_s->conf->ctrl_interface == NULL)
541 		return priv;
542 
543 	if (wpas_ctrl_iface_open_sock(wpa_s, priv) < 0) {
544 		os_free(priv);
545 		return NULL;
546 	}
547 
548 	return priv;
549 }
550 
551 
552 static int wpas_ctrl_iface_reinit(struct wpa_supplicant *wpa_s,
553 				  struct ctrl_iface_priv *priv)
554 {
555 	int res;
556 
557 	if (priv->sock <= 0)
558 		return -1;
559 
560 	eloop_unregister_read_sock(priv->sock);
561 	close(priv->sock);
562 	priv->sock = -1;
563 	res = wpas_ctrl_iface_open_sock(wpa_s, priv);
564 	if (res < 0)
565 		return -1;
566 	return priv->sock;
567 }
568 
569 
570 void wpa_supplicant_ctrl_iface_deinit(struct ctrl_iface_priv *priv)
571 {
572 	struct wpa_ctrl_dst *dst, *prev;
573 
574 	if (priv->sock > -1) {
575 		char *fname;
576 		char *buf, *dir = NULL, *gid_str = NULL;
577 		eloop_unregister_read_sock(priv->sock);
578 		if (!dl_list_empty(&priv->ctrl_dst)) {
579 			/*
580 			 * Wait before closing the control socket if
581 			 * there are any attached monitors in order to allow
582 			 * them to receive any pending messages.
583 			 */
584 			wpa_printf(MSG_DEBUG, "CTRL_IFACE wait for attached "
585 				   "monitors to receive messages");
586 			os_sleep(0, 100000);
587 		}
588 		close(priv->sock);
589 		priv->sock = -1;
590 		fname = wpa_supplicant_ctrl_iface_path(priv->wpa_s);
591 		if (fname) {
592 			unlink(fname);
593 			os_free(fname);
594 		}
595 
596 		if (priv->wpa_s->conf->ctrl_interface == NULL)
597 			goto free_dst;
598 		buf = os_strdup(priv->wpa_s->conf->ctrl_interface);
599 		if (buf == NULL)
600 			goto free_dst;
601 		if (os_strncmp(buf, "DIR=", 4) == 0) {
602 			dir = buf + 4;
603 			gid_str = os_strstr(dir, " GROUP=");
604 			if (gid_str) {
605 				*gid_str = '\0';
606 				gid_str += 7;
607 			}
608 		} else
609 			dir = buf;
610 
611 		if (rmdir(dir) < 0) {
612 			if (errno == ENOTEMPTY) {
613 				wpa_printf(MSG_DEBUG, "Control interface "
614 					   "directory not empty - leaving it "
615 					   "behind");
616 			} else {
617 				wpa_printf(MSG_ERROR,
618 					   "rmdir[ctrl_interface=%s]: %s",
619 					   dir, strerror(errno));
620 			}
621 		}
622 		os_free(buf);
623 	}
624 
625 free_dst:
626 	dl_list_for_each_safe(dst, prev, &priv->ctrl_dst, struct wpa_ctrl_dst,
627 			      list)
628 		os_free(dst);
629 	os_free(priv);
630 }
631 
632 
633 /**
634  * wpa_supplicant_ctrl_iface_send - Send a control interface packet to monitors
635  * @ifname: Interface name for global control socket or %NULL
636  * @sock: Local socket fd
637  * @ctrl_dst: List of attached listeners
638  * @level: Priority level of the message
639  * @buf: Message data
640  * @len: Message length
641  *
642  * Send a packet to all monitor programs attached to the control interface.
643  */
644 static void wpa_supplicant_ctrl_iface_send(struct wpa_supplicant *wpa_s,
645 					   const char *ifname, int sock,
646 					   struct dl_list *ctrl_dst,
647 					   int level, const char *buf,
648 					   size_t len,
649 					   struct ctrl_iface_priv *priv,
650 					   struct ctrl_iface_global_priv *gp)
651 {
652 	struct wpa_ctrl_dst *dst, *next;
653 	char levelstr[10];
654 	int idx, res;
655 	struct msghdr msg;
656 	struct iovec io[5];
657 
658 	if (sock < 0 || dl_list_empty(ctrl_dst))
659 		return;
660 
661 	res = os_snprintf(levelstr, sizeof(levelstr), "<%d>", level);
662 	if (res < 0 || (size_t) res >= sizeof(levelstr))
663 		return;
664 	idx = 0;
665 	if (ifname) {
666 		io[idx].iov_base = "IFNAME=";
667 		io[idx].iov_len = 7;
668 		idx++;
669 		io[idx].iov_base = (char *) ifname;
670 		io[idx].iov_len = os_strlen(ifname);
671 		idx++;
672 		io[idx].iov_base = " ";
673 		io[idx].iov_len = 1;
674 		idx++;
675 	}
676 	io[idx].iov_base = levelstr;
677 	io[idx].iov_len = os_strlen(levelstr);
678 	idx++;
679 	io[idx].iov_base = (char *) buf;
680 	io[idx].iov_len = len;
681 	idx++;
682 	os_memset(&msg, 0, sizeof(msg));
683 	msg.msg_iov = io;
684 	msg.msg_iovlen = idx;
685 
686 	dl_list_for_each_safe(dst, next, ctrl_dst, struct wpa_ctrl_dst, list) {
687 		int _errno;
688 		char addr_txt[200];
689 
690 		if (level < dst->debug_level)
691 			continue;
692 
693 		printf_encode(addr_txt, sizeof(addr_txt),
694 			      (u8 *) dst->addr.sun_path, dst->addrlen -
695 			      offsetof(struct sockaddr_un, sun_path));
696 		msg.msg_name = (void *) &dst->addr;
697 		msg.msg_namelen = dst->addrlen;
698 		if (sendmsg(sock, &msg, MSG_DONTWAIT) >= 0) {
699 			wpa_printf(MSG_DEBUG, "CTRL_IFACE monitor sent successfully to %s",
700 				   addr_txt);
701 			dst->errors = 0;
702 			continue;
703 		}
704 
705 		_errno = errno;
706 		wpa_printf(MSG_DEBUG, "CTRL_IFACE monitor[%s]: %d - %s",
707 			   addr_txt, errno, strerror(errno));
708 		dst->errors++;
709 
710 		if (dst->errors > 10 || _errno == ENOENT || _errno == EPERM) {
711 			wpa_printf(MSG_INFO, "CTRL_IFACE: Detach monitor %s that cannot receive messages",
712 				addr_txt);
713 			wpa_supplicant_ctrl_iface_detach(ctrl_dst, &dst->addr,
714 							 dst->addrlen);
715 		}
716 
717 		if (_errno == ENOBUFS || _errno == EAGAIN) {
718 			/*
719 			 * The socket send buffer could be full. This may happen
720 			 * if client programs are not receiving their pending
721 			 * messages. Close and reopen the socket as a workaround
722 			 * to avoid getting stuck being unable to send any new
723 			 * responses.
724 			 */
725 			if (priv)
726 				sock = wpas_ctrl_iface_reinit(wpa_s, priv);
727 			else if (gp)
728 				sock = wpas_ctrl_iface_global_reinit(
729 					wpa_s->global, gp);
730 			else
731 				break;
732 			if (sock < 0) {
733 				wpa_dbg(wpa_s, MSG_DEBUG,
734 					"Failed to reinitialize ctrl_iface socket");
735 				break;
736 			}
737 		}
738 	}
739 }
740 
741 
742 void wpa_supplicant_ctrl_iface_wait(struct ctrl_iface_priv *priv)
743 {
744 	char buf[256];
745 	int res;
746 	struct sockaddr_un from;
747 	socklen_t fromlen = sizeof(from);
748 
749 	for (;;) {
750 		wpa_printf(MSG_DEBUG, "CTRL_IFACE - %s - wait for monitor to "
751 			   "attach", priv->wpa_s->ifname);
752 		eloop_wait_for_read_sock(priv->sock);
753 
754 		res = recvfrom(priv->sock, buf, sizeof(buf) - 1, 0,
755 			       (struct sockaddr *) &from, &fromlen);
756 		if (res < 0) {
757 			wpa_printf(MSG_ERROR, "recvfrom(ctrl_iface): %s",
758 				   strerror(errno));
759 			continue;
760 		}
761 		buf[res] = '\0';
762 
763 		if (os_strcmp(buf, "ATTACH") == 0) {
764 			/* handle ATTACH signal of first monitor interface */
765 			if (!wpa_supplicant_ctrl_iface_attach(&priv->ctrl_dst,
766 							      &from, fromlen)) {
767 				if (sendto(priv->sock, "OK\n", 3, 0,
768 					   (struct sockaddr *) &from, fromlen) <
769 				    0) {
770 					wpa_printf(MSG_DEBUG, "ctrl_iface sendto failed: %s",
771 						   strerror(errno));
772 				}
773 				/* OK to continue */
774 				return;
775 			} else {
776 				if (sendto(priv->sock, "FAIL\n", 5, 0,
777 					   (struct sockaddr *) &from, fromlen) <
778 				    0) {
779 					wpa_printf(MSG_DEBUG, "ctrl_iface sendto failed: %s",
780 						   strerror(errno));
781 				}
782 			}
783 		} else {
784 			/* return FAIL for all other signals */
785 			if (sendto(priv->sock, "FAIL\n", 5, 0,
786 				   (struct sockaddr *) &from, fromlen) < 0) {
787 				wpa_printf(MSG_DEBUG,
788 					   "ctrl_iface sendto failed: %s",
789 					   strerror(errno));
790 			}
791 		}
792 	}
793 }
794 
795 
796 /* Global ctrl_iface */
797 
798 static void wpa_supplicant_global_ctrl_iface_receive(int sock, void *eloop_ctx,
799 						     void *sock_ctx)
800 {
801 	struct wpa_global *global = eloop_ctx;
802 	struct ctrl_iface_global_priv *priv = sock_ctx;
803 	char buf[4096];
804 	int res;
805 	struct sockaddr_un from;
806 	socklen_t fromlen = sizeof(from);
807 	char *reply = NULL, *reply_buf = NULL;
808 	size_t reply_len;
809 
810 	res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
811 		       (struct sockaddr *) &from, &fromlen);
812 	if (res < 0) {
813 		wpa_printf(MSG_ERROR, "recvfrom(ctrl_iface): %s",
814 			   strerror(errno));
815 		return;
816 	}
817 	buf[res] = '\0';
818 
819 	if (os_strcmp(buf, "ATTACH") == 0) {
820 		if (wpa_supplicant_ctrl_iface_attach(&priv->ctrl_dst, &from,
821 						     fromlen))
822 			reply_len = 1;
823 		else
824 			reply_len = 2;
825 	} else if (os_strcmp(buf, "DETACH") == 0) {
826 		if (wpa_supplicant_ctrl_iface_detach(&priv->ctrl_dst, &from,
827 						     fromlen))
828 			reply_len = 1;
829 		else
830 			reply_len = 2;
831 	} else {
832 		reply_buf = wpa_supplicant_global_ctrl_iface_process(
833 			global, buf, &reply_len);
834 		reply = reply_buf;
835 	}
836 
837 	if (!reply && reply_len == 1) {
838 		reply = "FAIL\n";
839 		reply_len = 5;
840 	} else if (!reply && reply_len == 2) {
841 		reply = "OK\n";
842 		reply_len = 3;
843 	}
844 
845 	if (reply) {
846 		if (sendto(sock, reply, reply_len, 0, (struct sockaddr *) &from,
847 			   fromlen) < 0) {
848 			wpa_printf(MSG_DEBUG, "ctrl_iface sendto failed: %s",
849 				strerror(errno));
850 		}
851 	}
852 	os_free(reply_buf);
853 }
854 
855 
856 static int wpas_global_ctrl_iface_open_sock(struct wpa_global *global,
857 					    struct ctrl_iface_global_priv *priv)
858 {
859 	struct sockaddr_un addr;
860 	const char *ctrl = global->params.ctrl_interface;
861 	int flags;
862 
863 	wpa_printf(MSG_DEBUG, "Global control interface '%s'", ctrl);
864 
865 #ifdef ANDROID
866 	if (os_strncmp(ctrl, "@android:", 9) == 0) {
867 		priv->sock = android_get_control_socket(ctrl + 9);
868 		if (priv->sock < 0) {
869 			wpa_printf(MSG_ERROR, "Failed to open Android control "
870 				   "socket '%s'", ctrl + 9);
871 			goto fail;
872 		}
873 		wpa_printf(MSG_DEBUG, "Using Android control socket '%s'",
874 			   ctrl + 9);
875 		goto havesock;
876 	}
877 
878 	if (os_strncmp(ctrl, "@abstract:", 10) != 0) {
879 		/*
880 		 * Backwards compatibility - try to open an Android control
881 		 * socket and if that fails, assume this was a UNIX domain
882 		 * socket instead.
883 		 */
884 		priv->sock = android_get_control_socket(ctrl);
885 		if (priv->sock >= 0) {
886 			wpa_printf(MSG_DEBUG,
887 				   "Using Android control socket '%s'",
888 				   ctrl);
889 			goto havesock;
890 		}
891 	}
892 #endif /* ANDROID */
893 
894 	priv->sock = socket(PF_UNIX, SOCK_DGRAM, 0);
895 	if (priv->sock < 0) {
896 		wpa_printf(MSG_ERROR, "socket(PF_UNIX): %s", strerror(errno));
897 		goto fail;
898 	}
899 
900 	os_memset(&addr, 0, sizeof(addr));
901 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
902 	addr.sun_len = sizeof(addr);
903 #endif /* __FreeBSD__ */
904 	addr.sun_family = AF_UNIX;
905 
906 	if (os_strncmp(ctrl, "@abstract:", 10) == 0) {
907 		addr.sun_path[0] = '\0';
908 		os_strlcpy(addr.sun_path + 1, ctrl + 10,
909 			   sizeof(addr.sun_path) - 1);
910 		if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) <
911 		    0) {
912 			wpa_printf(MSG_ERROR, "supp-global-ctrl-iface-init: "
913 				   "bind(PF_UNIX;%s) failed: %s",
914 				   ctrl, strerror(errno));
915 			goto fail;
916 		}
917 		wpa_printf(MSG_DEBUG, "Using Abstract control socket '%s'",
918 			   ctrl + 10);
919 		goto havesock;
920 	}
921 
922 	os_strlcpy(addr.sun_path, ctrl, sizeof(addr.sun_path));
923 	if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
924 		wpa_printf(MSG_INFO, "supp-global-ctrl-iface-init(%s) (will try fixup): bind(PF_UNIX): %s",
925 			   ctrl, strerror(errno));
926 		if (connect(priv->sock, (struct sockaddr *) &addr,
927 			    sizeof(addr)) < 0) {
928 			wpa_printf(MSG_DEBUG, "ctrl_iface exists, but does not"
929 				   " allow connections - assuming it was left"
930 				   "over from forced program termination");
931 			if (unlink(ctrl) < 0) {
932 				wpa_printf(MSG_ERROR,
933 					   "Could not unlink existing ctrl_iface socket '%s': %s",
934 					   ctrl, strerror(errno));
935 				goto fail;
936 			}
937 			if (bind(priv->sock, (struct sockaddr *) &addr,
938 				 sizeof(addr)) < 0) {
939 				wpa_printf(MSG_ERROR, "supp-glb-iface-init: bind(PF_UNIX;%s): %s",
940 					   ctrl, strerror(errno));
941 				goto fail;
942 			}
943 			wpa_printf(MSG_DEBUG, "Successfully replaced leftover "
944 				   "ctrl_iface socket '%s'",
945 				   ctrl);
946 		} else {
947 			wpa_printf(MSG_INFO, "ctrl_iface exists and seems to "
948 				   "be in use - cannot override it");
949 			wpa_printf(MSG_INFO, "Delete '%s' manually if it is "
950 				   "not used anymore",
951 				   ctrl);
952 			goto fail;
953 		}
954 	}
955 
956 	wpa_printf(MSG_DEBUG, "Using UNIX control socket '%s'", ctrl);
957 
958 	if (global->params.ctrl_interface_group) {
959 		char *gid_str = global->params.ctrl_interface_group;
960 		gid_t gid = 0;
961 		struct group *grp;
962 		char *endp;
963 
964 		grp = getgrnam(gid_str);
965 		if (grp) {
966 			gid = grp->gr_gid;
967 			wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d"
968 				   " (from group name '%s')",
969 				   (int) gid, gid_str);
970 		} else {
971 			/* Group name not found - try to parse this as gid */
972 			gid = strtol(gid_str, &endp, 10);
973 			if (*gid_str == '\0' || *endp != '\0') {
974 				wpa_printf(MSG_ERROR, "CTRL: Invalid group "
975 					   "'%s'", gid_str);
976 				goto fail;
977 			}
978 			wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d",
979 				   (int) gid);
980 		}
981 		if (chown(ctrl, -1, gid) < 0) {
982 			wpa_printf(MSG_ERROR,
983 				   "chown[global_ctrl_interface=%s,gid=%d]: %s",
984 				   ctrl, (int) gid, strerror(errno));
985 			goto fail;
986 		}
987 
988 		if (chmod(ctrl, S_IRWXU | S_IRWXG) < 0) {
989 			wpa_printf(MSG_ERROR,
990 				   "chmod[global_ctrl_interface=%s]: %s",
991 				   ctrl, strerror(errno));
992 			goto fail;
993 		}
994 	} else {
995 		chmod(ctrl, S_IRWXU);
996 	}
997 
998 havesock:
999 
1000 	/*
1001 	 * Make socket non-blocking so that we don't hang forever if
1002 	 * target dies unexpectedly.
1003 	 */
1004 	flags = fcntl(priv->sock, F_GETFL);
1005 	if (flags >= 0) {
1006 		flags |= O_NONBLOCK;
1007 		if (fcntl(priv->sock, F_SETFL, flags) < 0) {
1008 			wpa_printf(MSG_INFO, "fcntl(ctrl, O_NONBLOCK): %s",
1009 				   strerror(errno));
1010 			/* Not fatal, continue on.*/
1011 		}
1012 	}
1013 
1014 	eloop_register_read_sock(priv->sock,
1015 				 wpa_supplicant_global_ctrl_iface_receive,
1016 				 global, priv);
1017 
1018 	return 0;
1019 
1020 fail:
1021 	if (priv->sock >= 0) {
1022 		close(priv->sock);
1023 		priv->sock = -1;
1024 	}
1025 	return -1;
1026 }
1027 
1028 
1029 struct ctrl_iface_global_priv *
1030 wpa_supplicant_global_ctrl_iface_init(struct wpa_global *global)
1031 {
1032 	struct ctrl_iface_global_priv *priv;
1033 
1034 	priv = os_zalloc(sizeof(*priv));
1035 	if (priv == NULL)
1036 		return NULL;
1037 	dl_list_init(&priv->ctrl_dst);
1038 	priv->global = global;
1039 	priv->sock = -1;
1040 
1041 	if (global->params.ctrl_interface == NULL)
1042 		return priv;
1043 
1044 	if (wpas_global_ctrl_iface_open_sock(global, priv) < 0) {
1045 		os_free(priv);
1046 		return NULL;
1047 	}
1048 
1049 	wpa_msg_register_cb(wpa_supplicant_ctrl_iface_msg_cb);
1050 
1051 	return priv;
1052 }
1053 
1054 
1055 static int wpas_ctrl_iface_global_reinit(struct wpa_global *global,
1056 					 struct ctrl_iface_global_priv *priv)
1057 {
1058 	int res;
1059 
1060 	if (priv->sock <= 0)
1061 		return -1;
1062 
1063 	eloop_unregister_read_sock(priv->sock);
1064 	close(priv->sock);
1065 	priv->sock = -1;
1066 	res = wpas_global_ctrl_iface_open_sock(global, priv);
1067 	if (res < 0)
1068 		return -1;
1069 	return priv->sock;
1070 }
1071 
1072 
1073 void
1074 wpa_supplicant_global_ctrl_iface_deinit(struct ctrl_iface_global_priv *priv)
1075 {
1076 	struct wpa_ctrl_dst *dst, *prev;
1077 
1078 	if (priv->sock >= 0) {
1079 		eloop_unregister_read_sock(priv->sock);
1080 		close(priv->sock);
1081 	}
1082 	if (priv->global->params.ctrl_interface)
1083 		unlink(priv->global->params.ctrl_interface);
1084 	dl_list_for_each_safe(dst, prev, &priv->ctrl_dst, struct wpa_ctrl_dst,
1085 			      list)
1086 		os_free(dst);
1087 	os_free(priv);
1088 }
1089