xref: /freebsd/contrib/wpa/src/wps/wps_upnp.c (revision 7079fc4e0236ff334c2fb0f4367159be6df39332)
1 /*
2  * UPnP WPS Device
3  * Copyright (c) 2000-2003 Intel Corporation
4  * Copyright (c) 2006-2007 Sony Corporation
5  * Copyright (c) 2008-2009 Atheros Communications
6  * Copyright (c) 2009-2010, Jouni Malinen <j@w1.fi>
7  *
8  * See below for more details on licensing and code history.
9  */
10 
11 /*
12  * This has been greatly stripped down from the original file
13  * (upnp_wps_device.c) by Ted Merrill, Atheros Communications
14  * in order to eliminate use of the bulky libupnp library etc.
15  *
16  * History:
17  * upnp_wps_device.c is/was a shim layer between wps_opt_upnp.c and
18  * the libupnp library.
19  * The layering (by Sony) was well done; only a very minor modification
20  * to API of upnp_wps_device.c was required.
21  * libupnp was found to be undesirable because:
22  * -- It consumed too much code and data space
23  * -- It uses multiple threads, making debugging more difficult
24  *      and possibly reducing reliability.
25  * -- It uses static variables and only supports one instance.
26  * The shim and libupnp are here replaced by special code written
27  * specifically for the needs of hostapd.
28  * Various shortcuts can and are taken to keep the code size small.
29  * Generally, execution time is not as crucial.
30  *
31  * BUGS:
32  * -- UPnP requires that we be able to resolve domain names.
33  * While uncommon, if we have to do it then it will stall the entire
34  * hostapd program, which is bad.
35  * This is because we use the standard linux getaddrinfo() function
36  * which is syncronous.
37  * An asyncronous solution would be to use the free "ares" library.
38  * -- Does not have a robust output buffering scheme.  Uses a single
39  * fixed size output buffer per TCP/HTTP connection, with possible (although
40  * unlikely) possibility of overflow and likely excessive use of RAM.
41  * A better solution would be to write the HTTP output as a buffered stream,
42  * using chunking: (handle header specially, then) generate data with
43  * a printf-like function into a buffer, catching buffer full condition,
44  * then send it out surrounded by http chunking.
45  * -- There is some code that could be separated out into the common
46  * library to be shared with wpa_supplicant.
47  * -- Needs renaming with module prefix to avoid polluting the debugger
48  * namespace and causing possible collisions with other static fncs
49  * and structure declarations when using the debugger.
50  * -- The http error code generation is pretty bogus, hopefully no one cares.
51  *
52  * Author: Ted Merrill, Atheros Communications, based upon earlier work
53  * as explained above and below.
54  *
55  * Copyright:
56  * Copyright 2008 Atheros Communications.
57  *
58  * The original header (of upnp_wps_device.c) reads:
59  *
60  *  Copyright (c) 2006-2007 Sony Corporation. All Rights Reserved.
61  *
62  *  File Name: upnp_wps_device.c
63  *  Description: EAP-WPS UPnP device source
64  *
65  *   Redistribution and use in source and binary forms, with or without
66  *   modification, are permitted provided that the following conditions
67  *   are met:
68  *
69  *     * Redistributions of source code must retain the above copyright
70  *       notice, this list of conditions and the following disclaimer.
71  *     * Redistributions in binary form must reproduce the above copyright
72  *       notice, this list of conditions and the following disclaimer in
73  *       the documentation and/or other materials provided with the
74  *       distribution.
75  *     * Neither the name of Sony Corporation nor the names of its
76  *       contributors may be used to endorse or promote products derived
77  *       from this software without specific prior written permission.
78  *
79  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
80  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
81  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
82  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
83  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
84  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
85  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
86  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
87  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
88  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
89  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
90  *
91  * Portions from Intel libupnp files, e.g. genlib/net/http/httpreadwrite.c
92  * typical header:
93  *
94  * Copyright (c) 2000-2003 Intel Corporation
95  * All rights reserved.
96  *
97  * Redistribution and use in source and binary forms, with or without
98  * modification, are permitted provided that the following conditions are met:
99  *
100  * * Redistributions of source code must retain the above copyright notice,
101  * this list of conditions and the following disclaimer.
102  * * Redistributions in binary form must reproduce the above copyright notice,
103  * this list of conditions and the following disclaimer in the documentation
104  * and/or other materials provided with the distribution.
105  * * Neither name of Intel Corporation nor the names of its contributors
106  * may be used to endorse or promote products derived from this software
107  * without specific prior written permission.
108  *
109  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
110  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
111  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
112  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR
113  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
114  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
115  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
116  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
117  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
118  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
119  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
120 */
121 
122 /*
123  * Overview of WPS over UPnP:
124  *
125  * UPnP is a protocol that allows devices to discover each other and control
126  * each other. In UPnP terminology, a device is either a "device" (a server
127  * that provides information about itself and allows itself to be controlled)
128  * or a "control point" (a client that controls "devices") or possibly both.
129  * This file implements a UPnP "device".
130  *
131  * For us, we use mostly basic UPnP discovery, but the control part of interest
132  * is WPS carried via UPnP messages. There is quite a bit of basic UPnP
133  * discovery to do before we can get to WPS, however.
134  *
135  * UPnP discovery begins with "devices" send out multicast UDP packets to a
136  * certain fixed multicast IP address and port, and "control points" sending
137  * out other such UDP packets.
138  *
139  * The packets sent by devices are NOTIFY packets (not to be confused with TCP
140  * NOTIFY packets that are used later) and those sent by control points are
141  * M-SEARCH packets. These packets contain a simple HTTP style header. The
142  * packets are sent redundantly to get around packet loss. Devices respond to
143  * M-SEARCH packets with HTTP-like UDP packets containing HTTP/1.1 200 OK
144  * messages, which give similar information as the UDP NOTIFY packets.
145  *
146  * The above UDP packets advertise the (arbitrary) TCP ports that the
147  * respective parties will listen to. The control point can then do a HTTP
148  * SUBSCRIBE (something like an HTTP PUT) after which the device can do a
149  * separate HTTP NOTIFY (also like an HTTP PUT) to do event messaging.
150  *
151  * The control point will also do HTTP GET of the "device file" listed in the
152  * original UDP information from the device (see UPNP_WPS_DEVICE_XML_FILE
153  * data), and based on this will do additional GETs... HTTP POSTs are done to
154  * cause an action.
155  *
156  * Beyond some basic information in HTTP headers, additional information is in
157  * the HTTP bodies, in a format set by the SOAP and XML standards, a markup
158  * language related to HTML used for web pages. This language is intended to
159  * provide the ultimate in self-documentation by providing a universal
160  * namespace based on pseudo-URLs called URIs. Note that although a URI looks
161  * like a URL (a web address), they are never accessed as such but are used
162  * only as identifiers.
163  *
164  * The POST of a GetDeviceInfo gets information similar to what might be
165  * obtained from a probe request or response on Wi-Fi. WPS messages M1-M8
166  * are passed via a POST of a PutMessage; the M1-M8 WPS messages are converted
167  * to a bin64 ascii representation for encapsulation. When proxying messages,
168  * WLANEvent and PutWLANResponse are used.
169  *
170  * This of course glosses over a lot of details.
171  */
172 
173 #include "includes.h"
174 
175 #include <time.h>
176 #include <net/if.h>
177 #include <netdb.h>
178 #include <sys/ioctl.h>
179 
180 #include "common.h"
181 #include "uuid.h"
182 #include "base64.h"
183 #include "wps.h"
184 #include "wps_i.h"
185 #include "wps_upnp.h"
186 #include "wps_upnp_i.h"
187 
188 
189 /*
190  * UPnP allows a client ("control point") to send a server like us ("device")
191  * a domain name for registration, and we are supposed to resolve it. This is
192  * bad because, using the standard Linux library, we will stall the entire
193  * hostapd waiting for resolution.
194  *
195  * The "correct" solution would be to use an event driven library for domain
196  * name resolution such as "ares". However, this would increase code size
197  * further. Since it is unlikely that we'll actually see such domain names, we
198  * can just refuse to accept them.
199  */
200 #define NO_DOMAIN_NAME_RESOLUTION 1  /* 1 to allow only dotted ip addresses */
201 
202 
203 /*
204  * UPnP does not scale well. If we were in a room with thousands of control
205  * points then potentially we could be expected to handle subscriptions for
206  * each of them, which would exhaust our memory. So we must set a limit. In
207  * practice we are unlikely to see more than one or two.
208  */
209 #define MAX_SUBSCRIPTIONS 4    /* how many subscribing clients we handle */
210 #define MAX_ADDR_PER_SUBSCRIPTION 8
211 
212 /* Maximum number of Probe Request events per second */
213 #define MAX_EVENTS_PER_SEC 5
214 
215 
216 static struct upnp_wps_device_sm *shared_upnp_device = NULL;
217 
218 
219 /* Write the current date/time per RFC */
220 void format_date(struct wpabuf *buf)
221 {
222 	const char *weekday_str = "Sun\0Mon\0Tue\0Wed\0Thu\0Fri\0Sat";
223 	const char *month_str = "Jan\0Feb\0Mar\0Apr\0May\0Jun\0"
224 		"Jul\0Aug\0Sep\0Oct\0Nov\0Dec";
225 	struct tm *date;
226 	time_t t;
227 
228 	t = time(NULL);
229 	date = gmtime(&t);
230 	wpabuf_printf(buf, "%s, %02d %s %d %02d:%02d:%02d GMT",
231 		      &weekday_str[date->tm_wday * 4], date->tm_mday,
232 		      &month_str[date->tm_mon * 4], date->tm_year + 1900,
233 		      date->tm_hour, date->tm_min, date->tm_sec);
234 }
235 
236 
237 /***************************************************************************
238  * UUIDs (unique identifiers)
239  *
240  * These are supposed to be unique in all the world.
241  * Sometimes permanent ones are used, sometimes temporary ones
242  * based on random numbers... there are different rules for valid content
243  * of different types.
244  * Each uuid is 16 bytes long.
245  **************************************************************************/
246 
247 /* uuid_make -- construct a random UUID
248  * The UPnP documents don't seem to offer any guidelines as to which method to
249  * use for constructing UUIDs for subscriptions. Presumably any method from
250  * rfc4122 is good enough; I've chosen random number method.
251  */
252 static void uuid_make(u8 uuid[UUID_LEN])
253 {
254 	os_get_random(uuid, UUID_LEN);
255 
256 	/* Replace certain bits as specified in rfc4122 or X.667 */
257 	uuid[6] &= 0x0f; uuid[6] |= (4 << 4);   /* version 4 == random gen */
258 	uuid[8] &= 0x3f; uuid[8] |= 0x80;
259 }
260 
261 
262 /*
263  * Subscriber address handling.
264  * Since a subscriber may have an arbitrary number of addresses, we have to
265  * add a bunch of code to handle them.
266  *
267  * Addresses are passed in text, and MAY be domain names instead of the (usual
268  * and expected) dotted IP addresses. Resolving domain names consumes a lot of
269  * resources. Worse, we are currently using the standard Linux getaddrinfo()
270  * which will block the entire program until complete or timeout! The proper
271  * solution would be to use the "ares" library or similar with more state
272  * machine steps etc. or just disable domain name resolution by setting
273  * NO_DOMAIN_NAME_RESOLUTION to 1 at top of this file.
274  */
275 
276 /* subscr_addr_delete -- delete single unlinked subscriber address
277  * (be sure to unlink first if need be)
278  */
279 void subscr_addr_delete(struct subscr_addr *a)
280 {
281 	/*
282 	 * Note: do NOT free domain_and_port or path because they point to
283 	 * memory within the allocation of "a".
284 	 */
285 	os_free(a);
286 }
287 
288 
289 /* subscr_addr_free_all -- unlink and delete list of subscriber addresses. */
290 static void subscr_addr_free_all(struct subscription *s)
291 {
292 	struct subscr_addr *a, *tmp;
293 	dl_list_for_each_safe(a, tmp, &s->addr_list, struct subscr_addr, list)
294 	{
295 		dl_list_del(&a->list);
296 		subscr_addr_delete(a);
297 	}
298 }
299 
300 
301 /* subscr_addr_add_url -- add address(es) for one url to subscription */
302 static void subscr_addr_add_url(struct subscription *s, const char *url,
303 				size_t url_len)
304 {
305 	int alloc_len;
306 	char *scratch_mem = NULL;
307 	char *mem;
308 	char *host;
309 	char *delim;
310 	char *path;
311 	int port = 80;  /* port to send to (default is port 80) */
312 	struct addrinfo hints;
313 	struct addrinfo *result = NULL;
314 	struct addrinfo *rp;
315 	int rerr;
316 	size_t host_len, path_len;
317 
318 	/* url MUST begin with http: */
319 	if (url_len < 7 || os_strncasecmp(url, "http://", 7))
320 		goto fail;
321 	url += 7;
322 	url_len -= 7;
323 
324 	/* Make a copy of the string to allow modification during parsing */
325 	scratch_mem = os_malloc(url_len + 1);
326 	if (scratch_mem == NULL)
327 		goto fail;
328 	os_memcpy(scratch_mem, url, url_len);
329 	scratch_mem[url_len] = '\0';
330 	wpa_printf(MSG_DEBUG, "WPS UPnP: Adding URL '%s'", scratch_mem);
331 	host = scratch_mem;
332 	path = os_strchr(host, '/');
333 	if (path)
334 		*path++ = '\0'; /* null terminate host */
335 
336 	/* Process and remove optional port component */
337 	delim = os_strchr(host, ':');
338 	if (delim) {
339 		*delim = '\0'; /* null terminate host name for now */
340 		if (isdigit(delim[1]))
341 			port = atol(delim + 1);
342 	}
343 
344 	/*
345 	 * getaddrinfo does the right thing with dotted decimal notations, or
346 	 * will resolve domain names. Resolving domain names will unfortunately
347 	 * hang the entire program until it is resolved or it times out
348 	 * internal to getaddrinfo; fortunately we think that the use of actual
349 	 * domain names (vs. dotted decimal notations) should be uncommon.
350 	 */
351 	os_memset(&hints, 0, sizeof(struct addrinfo));
352 	hints.ai_family = AF_INET;      /* IPv4 */
353 	hints.ai_socktype = SOCK_STREAM;
354 #if NO_DOMAIN_NAME_RESOLUTION
355 	/* Suppress domain name resolutions that would halt
356 	 * the program for periods of time
357 	 */
358 	hints.ai_flags = AI_NUMERICHOST;
359 #else
360 	/* Allow domain name resolution. */
361 	hints.ai_flags = 0;
362 #endif
363 	hints.ai_protocol = 0;          /* Any protocol? */
364 	rerr = getaddrinfo(host, NULL /* fill in port ourselves */,
365 			   &hints, &result);
366 	if (rerr) {
367 		wpa_printf(MSG_INFO, "WPS UPnP: Resolve error %d (%s) on: %s",
368 			   rerr, gai_strerror(rerr), host);
369 		goto fail;
370 	}
371 
372 	if (delim)
373 		*delim = ':'; /* Restore port */
374 
375 	host_len = os_strlen(host);
376 	path_len = path ? os_strlen(path) : 0;
377 	alloc_len = host_len + 1 + 1 + path_len + 1;
378 
379 	for (rp = result; rp; rp = rp->ai_next) {
380 		struct subscr_addr *a;
381 
382 		/* Limit no. of address to avoid denial of service attack */
383 		if (dl_list_len(&s->addr_list) >= MAX_ADDR_PER_SUBSCRIPTION) {
384 			wpa_printf(MSG_INFO, "WPS UPnP: subscr_addr_add_url: "
385 				   "Ignoring excessive addresses");
386 			break;
387 		}
388 
389 		a = os_zalloc(sizeof(*a) + alloc_len);
390 		if (a == NULL)
391 			break;
392 		mem = (char *) (a + 1);
393 		a->domain_and_port = mem;
394 		os_memcpy(mem, host, host_len);
395 		mem += host_len + 1;
396 		a->path = mem;
397 		if (path == NULL || path[0] != '/')
398 			*mem++ = '/';
399 		if (path)
400 			os_memcpy(mem, path, path_len);
401 		os_memcpy(&a->saddr, rp->ai_addr, sizeof(a->saddr));
402 		a->saddr.sin_port = htons(port);
403 
404 		dl_list_add(&s->addr_list, &a->list);
405 	}
406 
407 fail:
408 	if (result)
409 		freeaddrinfo(result);
410 	os_free(scratch_mem);
411 }
412 
413 
414 /* subscr_addr_list_create -- create list from urls in string.
415  *      Each url is enclosed by angle brackets.
416  */
417 static void subscr_addr_list_create(struct subscription *s,
418 				    const char *url_list)
419 {
420 	const char *end;
421 	wpa_printf(MSG_DEBUG, "WPS UPnP: Parsing URL list '%s'", url_list);
422 	for (;;) {
423 		while (*url_list == ' ' || *url_list == '\t')
424 			url_list++;
425 		if (*url_list != '<')
426 			break;
427 		url_list++;
428 		end = os_strchr(url_list, '>');
429 		if (end == NULL)
430 			break;
431 		subscr_addr_add_url(s, url_list, end - url_list);
432 		url_list = end + 1;
433 	}
434 }
435 
436 
437 int send_wpabuf(int fd, struct wpabuf *buf)
438 {
439 	wpa_printf(MSG_DEBUG, "WPS UPnP: Send %lu byte message",
440 		   (unsigned long) wpabuf_len(buf));
441 	errno = 0;
442 	if (write(fd, wpabuf_head(buf), wpabuf_len(buf)) !=
443 	    (int) wpabuf_len(buf)) {
444 		wpa_printf(MSG_ERROR, "WPS UPnP: Failed to send buffer: "
445 			   "errno=%d (%s)",
446 			   errno, strerror(errno));
447 		return -1;
448 	}
449 
450 	return 0;
451 }
452 
453 
454 static void wpabuf_put_property(struct wpabuf *buf, const char *name,
455 				const char *value)
456 {
457 	wpabuf_put_str(buf, "<e:property>");
458 	wpabuf_printf(buf, "<%s>", name);
459 	if (value)
460 		wpabuf_put_str(buf, value);
461 	wpabuf_printf(buf, "</%s>", name);
462 	wpabuf_put_str(buf, "</e:property>\n");
463 }
464 
465 
466 /**
467  * upnp_wps_device_send_event - Queue event messages for subscribers
468  * @sm: WPS UPnP state machine from upnp_wps_device_init()
469  *
470  * This function queues the last WLANEvent to be sent for all currently
471  * subscribed UPnP control points. sm->wlanevent must have been set with the
472  * encoded data before calling this function.
473  */
474 static void upnp_wps_device_send_event(struct upnp_wps_device_sm *sm)
475 {
476 	/* Enqueue event message for all subscribers */
477 	struct wpabuf *buf; /* holds event message */
478 	int buf_size = 0;
479 	struct subscription *s, *tmp;
480 	/* Actually, utf-8 is the default, but it doesn't hurt to specify it */
481 	const char *format_head =
482 		"<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
483 		"<e:propertyset xmlns:e=\"urn:schemas-upnp-org:event-1-0\">\n";
484 	const char *format_tail = "</e:propertyset>\n";
485 	struct os_time now;
486 
487 	if (dl_list_empty(&sm->subscriptions)) {
488 		/* optimize */
489 		return;
490 	}
491 
492 	if (os_get_time(&now) == 0) {
493 		if (now.sec != sm->last_event_sec) {
494 			sm->last_event_sec = now.sec;
495 			sm->num_events_in_sec = 1;
496 		} else {
497 			sm->num_events_in_sec++;
498 			/*
499 			 * In theory, this should apply to all WLANEvent
500 			 * notifications, but EAP messages are of much higher
501 			 * priority and Probe Request notifications should not
502 			 * be allowed to drop EAP messages, so only throttle
503 			 * Probe Request notifications.
504 			 */
505 			if (sm->num_events_in_sec > MAX_EVENTS_PER_SEC &&
506 			    sm->wlanevent_type ==
507 			    UPNP_WPS_WLANEVENT_TYPE_PROBE) {
508 				wpa_printf(MSG_DEBUG, "WPS UPnP: Throttle "
509 					   "event notifications (%u seen "
510 					   "during one second)",
511 					   sm->num_events_in_sec);
512 				return;
513 			}
514 		}
515 	}
516 
517 	/* Determine buffer size needed first */
518 	buf_size += os_strlen(format_head);
519 	buf_size += 50 + 2 * os_strlen("WLANEvent");
520 	if (sm->wlanevent)
521 		buf_size += os_strlen(sm->wlanevent);
522 	buf_size += os_strlen(format_tail);
523 
524 	buf = wpabuf_alloc(buf_size);
525 	if (buf == NULL)
526 		return;
527 	wpabuf_put_str(buf, format_head);
528 	wpabuf_put_property(buf, "WLANEvent", sm->wlanevent);
529 	wpabuf_put_str(buf, format_tail);
530 
531 	wpa_printf(MSG_MSGDUMP, "WPS UPnP: WLANEvent message:\n%s",
532 		   (char *) wpabuf_head(buf));
533 
534 	dl_list_for_each_safe(s, tmp, &sm->subscriptions, struct subscription,
535 			      list) {
536 		event_add(s, buf,
537 			  sm->wlanevent_type == UPNP_WPS_WLANEVENT_TYPE_PROBE);
538 	}
539 
540 	wpabuf_free(buf);
541 }
542 
543 
544 /*
545  * Event subscription (subscriber machines register with us to receive event
546  * messages).
547  * This is the result of an incoming HTTP over TCP SUBSCRIBE request.
548  */
549 
550 /* subscription_destroy -- destroy an unlinked subscription
551  * Be sure to unlink first if necessary.
552  */
553 void subscription_destroy(struct subscription *s)
554 {
555 	struct upnp_wps_device_interface *iface;
556 	wpa_printf(MSG_DEBUG, "WPS UPnP: Destroy subscription %p", s);
557 	subscr_addr_free_all(s);
558 	event_delete_all(s);
559 	dl_list_for_each(iface, &s->sm->interfaces,
560 			 struct upnp_wps_device_interface, list)
561 		upnp_er_remove_notification(iface->wps->registrar, s);
562 	os_free(s);
563 }
564 
565 
566 /* subscription_list_age -- remove expired subscriptions */
567 static void subscription_list_age(struct upnp_wps_device_sm *sm, time_t now)
568 {
569 	struct subscription *s, *tmp;
570 	dl_list_for_each_safe(s, tmp, &sm->subscriptions,
571 			      struct subscription, list) {
572 		if (s->timeout_time > now)
573 			break;
574 		wpa_printf(MSG_DEBUG, "WPS UPnP: Removing aged subscription");
575 		dl_list_del(&s->list);
576 		subscription_destroy(s);
577 	}
578 }
579 
580 
581 /* subscription_find -- return existing subscription matching uuid, if any
582  * returns NULL if not found
583  */
584 struct subscription * subscription_find(struct upnp_wps_device_sm *sm,
585 					const u8 uuid[UUID_LEN])
586 {
587 	struct subscription *s;
588 	dl_list_for_each(s, &sm->subscriptions, struct subscription, list) {
589 		if (os_memcmp(s->uuid, uuid, UUID_LEN) == 0)
590 			return s; /* Found match */
591 	}
592 	return NULL;
593 }
594 
595 
596 static struct wpabuf * build_fake_wsc_ack(void)
597 {
598 	struct wpabuf *msg = wpabuf_alloc(100);
599 	if (msg == NULL)
600 		return NULL;
601 	wpabuf_put_u8(msg, UPNP_WPS_WLANEVENT_TYPE_EAP);
602 	wpabuf_put_str(msg, "00:00:00:00:00:00");
603 	if (wps_build_version(msg) ||
604 	    wps_build_msg_type(msg, WPS_WSC_ACK)) {
605 		wpabuf_free(msg);
606 		return NULL;
607 	}
608 	/* Enrollee Nonce */
609 	wpabuf_put_be16(msg, ATTR_ENROLLEE_NONCE);
610 	wpabuf_put_be16(msg, WPS_NONCE_LEN);
611 	wpabuf_put(msg, WPS_NONCE_LEN);
612 	/* Registrar Nonce */
613 	wpabuf_put_be16(msg, ATTR_REGISTRAR_NONCE);
614 	wpabuf_put_be16(msg, WPS_NONCE_LEN);
615 	wpabuf_put(msg, WPS_NONCE_LEN);
616 	wps_build_wfa_ext(msg, 0, NULL, 0);
617 	return msg;
618 }
619 
620 
621 /* subscription_first_event -- send format/queue event that is automatically
622  * sent on a new subscription.
623  */
624 static int subscription_first_event(struct subscription *s)
625 {
626 	/*
627 	 * Actually, utf-8 is the default, but it doesn't hurt to specify it.
628 	 *
629 	 * APStatus is apparently a bit set,
630 	 * 0x1 = configuration change (but is always set?)
631 	 * 0x10 = ap is locked
632 	 *
633 	 * Per UPnP spec, we send out the last value of each variable, even
634 	 * for WLANEvent, whatever it was.
635 	 */
636 	char *wlan_event;
637 	struct wpabuf *buf;
638 	int ap_status = 1;      /* TODO: add 0x10 if access point is locked */
639 	const char *head =
640 		"<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
641 		"<e:propertyset xmlns:e=\"urn:schemas-upnp-org:event-1-0\">\n";
642 	const char *tail = "</e:propertyset>\n";
643 	char txt[10];
644 	int ret;
645 
646 	if (s->sm->wlanevent == NULL) {
647 		/*
648 		 * There has been no events before the subscription. However,
649 		 * UPnP device architecture specification requires all the
650 		 * evented variables to be included, so generate a dummy event
651 		 * for this particular case using a WSC_ACK and all-zeros
652 		 * nonces. The ER (UPnP control point) will ignore this, but at
653 		 * least it will learn that WLANEvent variable will be used in
654 		 * event notifications in the future.
655 		 */
656 		struct wpabuf *msg;
657 		wpa_printf(MSG_DEBUG, "WPS UPnP: Use a fake WSC_ACK as the "
658 			   "initial WLANEvent");
659 		msg = build_fake_wsc_ack();
660 		if (msg) {
661 			s->sm->wlanevent = (char *)
662 				base64_encode(wpabuf_head(msg),
663 					      wpabuf_len(msg), NULL);
664 			wpabuf_free(msg);
665 		}
666 	}
667 
668 	wlan_event = s->sm->wlanevent;
669 	if (wlan_event == NULL || *wlan_event == '\0') {
670 		wpa_printf(MSG_DEBUG, "WPS UPnP: WLANEvent not known for "
671 			   "initial event message");
672 		wlan_event = "";
673 	}
674 	buf = wpabuf_alloc(500 + os_strlen(wlan_event));
675 	if (buf == NULL)
676 		return -1;
677 
678 	wpabuf_put_str(buf, head);
679 	wpabuf_put_property(buf, "STAStatus", "1");
680 	os_snprintf(txt, sizeof(txt), "%d", ap_status);
681 	wpabuf_put_property(buf, "APStatus", txt);
682 	if (*wlan_event)
683 		wpabuf_put_property(buf, "WLANEvent", wlan_event);
684 	wpabuf_put_str(buf, tail);
685 
686 	ret = event_add(s, buf, 0);
687 	if (ret) {
688 		wpabuf_free(buf);
689 		return ret;
690 	}
691 	wpabuf_free(buf);
692 
693 	return 0;
694 }
695 
696 
697 /**
698  * subscription_start - Remember a UPnP control point to send events to.
699  * @sm: WPS UPnP state machine from upnp_wps_device_init()
700  * @callback_urls: Callback URLs
701  * Returns: %NULL on error, or pointer to new subscription structure.
702  */
703 struct subscription * subscription_start(struct upnp_wps_device_sm *sm,
704 					 const char *callback_urls)
705 {
706 	struct subscription *s;
707 	time_t now = time(NULL);
708 	time_t expire = now + UPNP_SUBSCRIBE_SEC;
709 
710 	/* Get rid of expired subscriptions so we have room */
711 	subscription_list_age(sm, now);
712 
713 	/* If too many subscriptions, remove oldest */
714 	if (dl_list_len(&sm->subscriptions) >= MAX_SUBSCRIPTIONS) {
715 		s = dl_list_first(&sm->subscriptions, struct subscription,
716 				  list);
717 		wpa_printf(MSG_INFO, "WPS UPnP: Too many subscriptions, "
718 			   "trashing oldest");
719 		dl_list_del(&s->list);
720 		subscription_destroy(s);
721 	}
722 
723 	s = os_zalloc(sizeof(*s));
724 	if (s == NULL)
725 		return NULL;
726 	dl_list_init(&s->addr_list);
727 	dl_list_init(&s->event_queue);
728 
729 	s->sm = sm;
730 	s->timeout_time = expire;
731 	uuid_make(s->uuid);
732 	subscr_addr_list_create(s, callback_urls);
733 	if (dl_list_empty(&s->addr_list)) {
734 		wpa_printf(MSG_DEBUG, "WPS UPnP: No valid callback URLs in "
735 			   "'%s' - drop subscription", callback_urls);
736 		subscription_destroy(s);
737 		return NULL;
738 	}
739 
740 	/* Add to end of list, since it has the highest expiration time */
741 	dl_list_add_tail(&sm->subscriptions, &s->list);
742 	/* Queue up immediate event message (our last event)
743 	 * as required by UPnP spec.
744 	 */
745 	if (subscription_first_event(s)) {
746 		wpa_printf(MSG_INFO, "WPS UPnP: Dropping subscriber due to "
747 			   "event backlog");
748 		dl_list_del(&s->list);
749 		subscription_destroy(s);
750 		return NULL;
751 	}
752 	wpa_printf(MSG_DEBUG, "WPS UPnP: Subscription %p started with %s",
753 		   s, callback_urls);
754 	/* Schedule sending this */
755 	event_send_all_later(sm);
756 	return s;
757 }
758 
759 
760 /* subscription_renew -- find subscription and reset timeout */
761 struct subscription * subscription_renew(struct upnp_wps_device_sm *sm,
762 					 const u8 uuid[UUID_LEN])
763 {
764 	time_t now = time(NULL);
765 	time_t expire = now + UPNP_SUBSCRIBE_SEC;
766 	struct subscription *s = subscription_find(sm, uuid);
767 	if (s == NULL)
768 		return NULL;
769 	wpa_printf(MSG_DEBUG, "WPS UPnP: Subscription renewed");
770 	dl_list_del(&s->list);
771 	s->timeout_time = expire;
772 	/* add back to end of list, since it now has highest expiry */
773 	dl_list_add_tail(&sm->subscriptions, &s->list);
774 	return s;
775 }
776 
777 
778 /**
779  * upnp_wps_device_send_wlan_event - Event notification
780  * @sm: WPS UPnP state machine from upnp_wps_device_init()
781  * @from_mac_addr: Source (Enrollee) MAC address for the event
782  * @ev_type: Event type
783  * @msg: Event data
784  * Returns: 0 on success, -1 on failure
785  *
786  * Tell external Registrars (UPnP control points) that something happened. In
787  * particular, events include WPS messages from clients that are proxied to
788  * external Registrars.
789  */
790 int upnp_wps_device_send_wlan_event(struct upnp_wps_device_sm *sm,
791 				    const u8 from_mac_addr[ETH_ALEN],
792 				    enum upnp_wps_wlanevent_type ev_type,
793 				    const struct wpabuf *msg)
794 {
795 	int ret = -1;
796 	char type[2];
797 	const u8 *mac = from_mac_addr;
798 	char mac_text[18];
799 	u8 *raw = NULL;
800 	size_t raw_len;
801 	char *val;
802 	size_t val_len;
803 	int pos = 0;
804 
805 	if (!sm)
806 		goto fail;
807 
808 	os_snprintf(type, sizeof(type), "%1u", ev_type);
809 
810 	raw_len = 1 + 17 + (msg ? wpabuf_len(msg) : 0);
811 	raw = os_zalloc(raw_len);
812 	if (!raw)
813 		goto fail;
814 
815 	*(raw + pos) = (u8) ev_type;
816 	pos += 1;
817 	os_snprintf(mac_text, sizeof(mac_text), MACSTR, MAC2STR(mac));
818 	wpa_printf(MSG_DEBUG, "WPS UPnP: Proxying WLANEvent from %s",
819 		   mac_text);
820 	os_memcpy(raw + pos, mac_text, 17);
821 	pos += 17;
822 	if (msg) {
823 		os_memcpy(raw + pos, wpabuf_head(msg), wpabuf_len(msg));
824 		pos += wpabuf_len(msg);
825 	}
826 	raw_len = pos;
827 
828 	val = (char *) base64_encode(raw, raw_len, &val_len);
829 	if (val == NULL)
830 		goto fail;
831 
832 	os_free(sm->wlanevent);
833 	sm->wlanevent = val;
834 	sm->wlanevent_type = ev_type;
835 	upnp_wps_device_send_event(sm);
836 
837 	ret = 0;
838 
839 fail:
840 	os_free(raw);
841 
842 	return ret;
843 }
844 
845 
846 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
847 #include <sys/sysctl.h>
848 #include <net/route.h>
849 #include <net/if_dl.h>
850 
851 static int eth_get(const char *device, u8 ea[ETH_ALEN])
852 {
853 	struct if_msghdr *ifm;
854 	struct sockaddr_dl *sdl;
855 	u_char *p, *buf;
856 	size_t len;
857 	int mib[] = { CTL_NET, AF_ROUTE, 0, AF_LINK, NET_RT_IFLIST, 0 };
858 
859 	if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0)
860 		return -1;
861 	if ((buf = os_malloc(len)) == NULL)
862 		return -1;
863 	if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
864 		os_free(buf);
865 		return -1;
866 	}
867 	for (p = buf; p < buf + len; p += ifm->ifm_msglen) {
868 		ifm = (struct if_msghdr *)p;
869 		sdl = (struct sockaddr_dl *)(ifm + 1);
870 		if (ifm->ifm_type != RTM_IFINFO ||
871 		    (ifm->ifm_addrs & RTA_IFP) == 0)
872 			continue;
873 		if (sdl->sdl_family != AF_LINK || sdl->sdl_nlen == 0 ||
874 		    os_memcmp(sdl->sdl_data, device, sdl->sdl_nlen) != 0)
875 			continue;
876 		os_memcpy(ea, LLADDR(sdl), sdl->sdl_alen);
877 		break;
878 	}
879 	os_free(buf);
880 
881 	if (p >= buf + len) {
882 		errno = ESRCH;
883 		return -1;
884 	}
885 	return 0;
886 }
887 #endif /* __FreeBSD__ */
888 
889 
890 /**
891  * get_netif_info - Get hw and IP addresses for network device
892  * @net_if: Selected network interface name
893  * @ip_addr: Buffer for returning IP address in network byte order
894  * @ip_addr_text: Buffer for returning a pointer to allocated IP address text
895  * @mac: Buffer for returning MAC address
896  * Returns: 0 on success, -1 on failure
897  */
898 int get_netif_info(const char *net_if, unsigned *ip_addr, char **ip_addr_text,
899 		   u8 mac[ETH_ALEN])
900 {
901 	struct ifreq req;
902 	int sock = -1;
903 	struct sockaddr_in *addr;
904 	struct in_addr in_addr;
905 
906 	*ip_addr_text = os_zalloc(16);
907 	if (*ip_addr_text == NULL)
908 		goto fail;
909 
910 	sock = socket(AF_INET, SOCK_DGRAM, 0);
911 	if (sock < 0)
912 		goto fail;
913 
914 	os_strlcpy(req.ifr_name, net_if, sizeof(req.ifr_name));
915 	if (ioctl(sock, SIOCGIFADDR, &req) < 0) {
916 		wpa_printf(MSG_ERROR, "WPS UPnP: SIOCGIFADDR failed: %d (%s)",
917 			   errno, strerror(errno));
918 		goto fail;
919 	}
920 	addr = (void *) &req.ifr_addr;
921 	*ip_addr = addr->sin_addr.s_addr;
922 	in_addr.s_addr = *ip_addr;
923 	os_snprintf(*ip_addr_text, 16, "%s", inet_ntoa(in_addr));
924 
925 #ifdef __linux__
926 	os_strlcpy(req.ifr_name, net_if, sizeof(req.ifr_name));
927 	if (ioctl(sock, SIOCGIFHWADDR, &req) < 0) {
928 		wpa_printf(MSG_ERROR, "WPS UPnP: SIOCGIFHWADDR failed: "
929 			   "%d (%s)", errno, strerror(errno));
930 		goto fail;
931 	}
932 	os_memcpy(mac, req.ifr_addr.sa_data, 6);
933 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
934 	if (eth_get(net_if, mac) < 0) {
935 		wpa_printf(MSG_ERROR, "WPS UPnP: Failed to get MAC address");
936 		goto fail;
937 	}
938 #else
939 #error MAC address fetch not implemented
940 #endif
941 
942 	close(sock);
943 	return 0;
944 
945 fail:
946 	if (sock >= 0)
947 		close(sock);
948 	os_free(*ip_addr_text);
949 	*ip_addr_text = NULL;
950 	return -1;
951 }
952 
953 
954 static void upnp_wps_free_msearchreply(struct dl_list *head)
955 {
956 	struct advertisement_state_machine *a, *tmp;
957 	dl_list_for_each_safe(a, tmp, head, struct advertisement_state_machine,
958 			      list)
959 		msearchreply_state_machine_stop(a);
960 }
961 
962 
963 static void upnp_wps_free_subscriptions(struct dl_list *head,
964 					struct wps_registrar *reg)
965 {
966 	struct subscription *s, *tmp;
967 	dl_list_for_each_safe(s, tmp, head, struct subscription, list) {
968 		if (reg && s->reg != reg)
969 			continue;
970 		dl_list_del(&s->list);
971 		subscription_destroy(s);
972 	}
973 }
974 
975 
976 /**
977  * upnp_wps_device_stop - Stop WPS UPnP operations on an interface
978  * @sm: WPS UPnP state machine from upnp_wps_device_init()
979  */
980 static void upnp_wps_device_stop(struct upnp_wps_device_sm *sm)
981 {
982 	if (!sm || !sm->started)
983 		return;
984 
985 	wpa_printf(MSG_DEBUG, "WPS UPnP: Stop device");
986 	web_listener_stop(sm);
987 	upnp_wps_free_msearchreply(&sm->msearch_replies);
988 	upnp_wps_free_subscriptions(&sm->subscriptions, NULL);
989 
990 	advertisement_state_machine_stop(sm, 1);
991 
992 	event_send_stop_all(sm);
993 	os_free(sm->wlanevent);
994 	sm->wlanevent = NULL;
995 	os_free(sm->ip_addr_text);
996 	sm->ip_addr_text = NULL;
997 	if (sm->multicast_sd >= 0)
998 		close(sm->multicast_sd);
999 	sm->multicast_sd = -1;
1000 	ssdp_listener_stop(sm);
1001 
1002 	sm->started = 0;
1003 }
1004 
1005 
1006 /**
1007  * upnp_wps_device_start - Start WPS UPnP operations on an interface
1008  * @sm: WPS UPnP state machine from upnp_wps_device_init()
1009  * @net_if: Selected network interface name
1010  * Returns: 0 on success, -1 on failure
1011  */
1012 static int upnp_wps_device_start(struct upnp_wps_device_sm *sm, char *net_if)
1013 {
1014 	if (!sm || !net_if)
1015 		return -1;
1016 
1017 	if (sm->started)
1018 		upnp_wps_device_stop(sm);
1019 
1020 	sm->multicast_sd = -1;
1021 	sm->ssdp_sd = -1;
1022 	sm->started = 1;
1023 	sm->advertise_count = 0;
1024 
1025 	/* Fix up linux multicast handling */
1026 	if (add_ssdp_network(net_if))
1027 		goto fail;
1028 
1029 	/* Determine which IP and mac address we're using */
1030 	if (get_netif_info(net_if, &sm->ip_addr, &sm->ip_addr_text,
1031 			   sm->mac_addr)) {
1032 		wpa_printf(MSG_INFO, "WPS UPnP: Could not get IP/MAC address "
1033 			   "for %s. Does it have IP address?", net_if);
1034 		goto fail;
1035 	}
1036 
1037 	/* Listen for incoming TCP connections so that others
1038 	 * can fetch our "xml files" from us.
1039 	 */
1040 	if (web_listener_start(sm))
1041 		goto fail;
1042 
1043 	/* Set up for receiving discovery (UDP) packets */
1044 	if (ssdp_listener_start(sm))
1045 		goto fail;
1046 
1047 	/* Set up for sending multicast */
1048 	if (ssdp_open_multicast(sm) < 0)
1049 		goto fail;
1050 
1051 	/*
1052 	 * Broadcast NOTIFY messages to let the world know we exist.
1053 	 * This is done via a state machine since the messages should not be
1054 	 * all sent out at once.
1055 	 */
1056 	if (advertisement_state_machine_start(sm))
1057 		goto fail;
1058 
1059 	return 0;
1060 
1061 fail:
1062 	upnp_wps_device_stop(sm);
1063 	return -1;
1064 }
1065 
1066 
1067 static struct upnp_wps_device_interface *
1068 upnp_wps_get_iface(struct upnp_wps_device_sm *sm, void *priv)
1069 {
1070 	struct upnp_wps_device_interface *iface;
1071 	dl_list_for_each(iface, &sm->interfaces,
1072 			 struct upnp_wps_device_interface, list) {
1073 		if (iface->priv == priv)
1074 			return iface;
1075 	}
1076 	return NULL;
1077 }
1078 
1079 
1080 /**
1081  * upnp_wps_device_deinit - Deinitialize WPS UPnP
1082  * @sm: WPS UPnP state machine from upnp_wps_device_init()
1083  * @priv: External context data that was used in upnp_wps_device_init() call
1084  */
1085 void upnp_wps_device_deinit(struct upnp_wps_device_sm *sm, void *priv)
1086 {
1087 	struct upnp_wps_device_interface *iface;
1088 
1089 	if (!sm)
1090 		return;
1091 
1092 	iface = upnp_wps_get_iface(sm, priv);
1093 	if (iface == NULL) {
1094 		wpa_printf(MSG_ERROR, "WPS UPnP: Could not find the interface "
1095 			   "instance to deinit");
1096 		return;
1097 	}
1098 	wpa_printf(MSG_DEBUG, "WPS UPnP: Deinit interface instance %p", iface);
1099 	if (dl_list_len(&sm->interfaces) == 1) {
1100 		wpa_printf(MSG_DEBUG, "WPS UPnP: Deinitializing last instance "
1101 			   "- free global device instance");
1102 		upnp_wps_device_stop(sm);
1103 	} else
1104 		upnp_wps_free_subscriptions(&sm->subscriptions,
1105 					    iface->wps->registrar);
1106 	dl_list_del(&iface->list);
1107 
1108 	if (iface->peer.wps)
1109 		wps_deinit(iface->peer.wps);
1110 	os_free(iface->ctx->ap_pin);
1111 	os_free(iface->ctx);
1112 	os_free(iface);
1113 
1114 	if (dl_list_empty(&sm->interfaces)) {
1115 		os_free(sm->root_dir);
1116 		os_free(sm->desc_url);
1117 		os_free(sm);
1118 		shared_upnp_device = NULL;
1119 	}
1120 }
1121 
1122 
1123 /**
1124  * upnp_wps_device_init - Initialize WPS UPnP
1125  * @ctx: callback table; we must eventually free it
1126  * @wps: Pointer to longterm WPS context
1127  * @priv: External context data that will be used in callbacks
1128  * @net_if: Selected network interface name
1129  * Returns: WPS UPnP state or %NULL on failure
1130  */
1131 struct upnp_wps_device_sm *
1132 upnp_wps_device_init(struct upnp_wps_device_ctx *ctx, struct wps_context *wps,
1133 		     void *priv, char *net_if)
1134 {
1135 	struct upnp_wps_device_sm *sm;
1136 	struct upnp_wps_device_interface *iface;
1137 	int start = 0;
1138 
1139 	iface = os_zalloc(sizeof(*iface));
1140 	if (iface == NULL) {
1141 		os_free(ctx->ap_pin);
1142 		os_free(ctx);
1143 		return NULL;
1144 	}
1145 	wpa_printf(MSG_DEBUG, "WPS UPnP: Init interface instance %p", iface);
1146 
1147 	iface->ctx = ctx;
1148 	iface->wps = wps;
1149 	iface->priv = priv;
1150 
1151 	if (shared_upnp_device) {
1152 		wpa_printf(MSG_DEBUG, "WPS UPnP: Share existing device "
1153 			   "context");
1154 		sm = shared_upnp_device;
1155 	} else {
1156 		wpa_printf(MSG_DEBUG, "WPS UPnP: Initialize device context");
1157 		sm = os_zalloc(sizeof(*sm));
1158 		if (!sm) {
1159 			wpa_printf(MSG_ERROR, "WPS UPnP: upnp_wps_device_init "
1160 				   "failed");
1161 			os_free(iface);
1162 			os_free(ctx->ap_pin);
1163 			os_free(ctx);
1164 			return NULL;
1165 		}
1166 		shared_upnp_device = sm;
1167 
1168 		dl_list_init(&sm->msearch_replies);
1169 		dl_list_init(&sm->subscriptions);
1170 		dl_list_init(&sm->interfaces);
1171 		start = 1;
1172 	}
1173 
1174 	dl_list_add(&sm->interfaces, &iface->list);
1175 
1176 	if (start && upnp_wps_device_start(sm, net_if)) {
1177 		upnp_wps_device_deinit(sm, priv);
1178 		return NULL;
1179 	}
1180 
1181 
1182 	return sm;
1183 }
1184 
1185 
1186 /**
1187  * upnp_wps_subscribers - Check whether there are any event subscribers
1188  * @sm: WPS UPnP state machine from upnp_wps_device_init()
1189  * Returns: 0 if no subscribers, 1 if subscribers
1190  */
1191 int upnp_wps_subscribers(struct upnp_wps_device_sm *sm)
1192 {
1193 	return !dl_list_empty(&sm->subscriptions);
1194 }
1195 
1196 
1197 int upnp_wps_set_ap_pin(struct upnp_wps_device_sm *sm, const char *ap_pin)
1198 {
1199 	struct upnp_wps_device_interface *iface;
1200 	if (sm == NULL)
1201 		return 0;
1202 
1203 	dl_list_for_each(iface, &sm->interfaces,
1204 			 struct upnp_wps_device_interface, list) {
1205 		os_free(iface->ctx->ap_pin);
1206 		if (ap_pin) {
1207 			iface->ctx->ap_pin = os_strdup(ap_pin);
1208 			if (iface->ctx->ap_pin == NULL)
1209 				return -1;
1210 		} else
1211 			iface->ctx->ap_pin = NULL;
1212 	}
1213 
1214 	return 0;
1215 }
1216