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 */
format_date(struct wpabuf * buf)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 if (date == NULL)
231 return;
232 wpabuf_printf(buf, "%s, %02d %s %d %02d:%02d:%02d GMT",
233 &weekday_str[date->tm_wday * 4], date->tm_mday,
234 &month_str[date->tm_mon * 4], date->tm_year + 1900,
235 date->tm_hour, date->tm_min, date->tm_sec);
236 }
237
238
239 /***************************************************************************
240 * UUIDs (unique identifiers)
241 *
242 * These are supposed to be unique in all the world.
243 * Sometimes permanent ones are used, sometimes temporary ones
244 * based on random numbers... there are different rules for valid content
245 * of different types.
246 * Each uuid is 16 bytes long.
247 **************************************************************************/
248
249 /* uuid_make -- construct a random UUID
250 * The UPnP documents don't seem to offer any guidelines as to which method to
251 * use for constructing UUIDs for subscriptions. Presumably any method from
252 * rfc4122 is good enough; I've chosen random number method.
253 */
uuid_make(u8 uuid[UUID_LEN])254 static int uuid_make(u8 uuid[UUID_LEN])
255 {
256 if (os_get_random(uuid, UUID_LEN) < 0)
257 return -1;
258
259 /* Replace certain bits as specified in rfc4122 or X.667 */
260 uuid[6] &= 0x0f; uuid[6] |= (4 << 4); /* version 4 == random gen */
261 uuid[8] &= 0x3f; uuid[8] |= 0x80;
262
263 return 0;
264 }
265
266
267 /*
268 * Subscriber address handling.
269 * Since a subscriber may have an arbitrary number of addresses, we have to
270 * add a bunch of code to handle them.
271 *
272 * Addresses are passed in text, and MAY be domain names instead of the (usual
273 * and expected) dotted IP addresses. Resolving domain names consumes a lot of
274 * resources. Worse, we are currently using the standard Linux getaddrinfo()
275 * which will block the entire program until complete or timeout! The proper
276 * solution would be to use the "ares" library or similar with more state
277 * machine steps etc. or just disable domain name resolution by setting
278 * NO_DOMAIN_NAME_RESOLUTION to 1 at top of this file.
279 */
280
281 /* subscr_addr_delete -- delete single unlinked subscriber address
282 * (be sure to unlink first if need be)
283 */
subscr_addr_delete(struct subscr_addr * a)284 void subscr_addr_delete(struct subscr_addr *a)
285 {
286 /*
287 * Note: do NOT free domain_and_port or path because they point to
288 * memory within the allocation of "a".
289 */
290 os_free(a);
291 }
292
293
294 /* subscr_addr_free_all -- unlink and delete list of subscriber addresses. */
subscr_addr_free_all(struct subscription * s)295 static void subscr_addr_free_all(struct subscription *s)
296 {
297 struct subscr_addr *a, *tmp;
298 dl_list_for_each_safe(a, tmp, &s->addr_list, struct subscr_addr, list)
299 {
300 dl_list_del(&a->list);
301 subscr_addr_delete(a);
302 }
303 }
304
305
306 /* subscr_addr_add_url -- add address(es) for one url to subscription */
subscr_addr_add_url(struct subscription * s,const char * url,size_t url_len)307 static void subscr_addr_add_url(struct subscription *s, const char *url,
308 size_t url_len)
309 {
310 int alloc_len;
311 char *scratch_mem = NULL;
312 char *mem;
313 char *host;
314 char *delim;
315 char *path;
316 int port = 80; /* port to send to (default is port 80) */
317 struct addrinfo hints;
318 struct addrinfo *result = NULL;
319 struct addrinfo *rp;
320 int rerr;
321 size_t host_len, path_len;
322
323 /* url MUST begin with http: */
324 if (url_len < 7 || os_strncasecmp(url, "http://", 7))
325 goto fail;
326 url += 7;
327 url_len -= 7;
328
329 /* Make a copy of the string to allow modification during parsing */
330 scratch_mem = dup_binstr(url, url_len);
331 if (scratch_mem == NULL)
332 goto fail;
333 wpa_printf(MSG_DEBUG, "WPS UPnP: Adding URL '%s'", scratch_mem);
334 host = scratch_mem;
335 path = os_strchr(host, '/');
336 if (path)
337 *path++ = '\0'; /* null terminate host */
338
339 /* Process and remove optional port component */
340 delim = os_strchr(host, ':');
341 if (delim) {
342 *delim = '\0'; /* null terminate host name for now */
343 if (isdigit(delim[1]))
344 port = atol(delim + 1);
345 }
346
347 /*
348 * getaddrinfo does the right thing with dotted decimal notations, or
349 * will resolve domain names. Resolving domain names will unfortunately
350 * hang the entire program until it is resolved or it times out
351 * internal to getaddrinfo; fortunately we think that the use of actual
352 * domain names (vs. dotted decimal notations) should be uncommon.
353 */
354 os_memset(&hints, 0, sizeof(struct addrinfo));
355 hints.ai_family = AF_INET; /* IPv4 */
356 hints.ai_socktype = SOCK_STREAM;
357 #if NO_DOMAIN_NAME_RESOLUTION
358 /* Suppress domain name resolutions that would halt
359 * the program for periods of time
360 */
361 hints.ai_flags = AI_NUMERICHOST;
362 #else
363 /* Allow domain name resolution. */
364 hints.ai_flags = 0;
365 #endif
366 hints.ai_protocol = 0; /* Any protocol? */
367 rerr = getaddrinfo(host, NULL /* fill in port ourselves */,
368 &hints, &result);
369 if (rerr) {
370 wpa_printf(MSG_INFO, "WPS UPnP: Resolve error %d (%s) on: %s",
371 rerr, gai_strerror(rerr), host);
372 goto fail;
373 }
374
375 if (delim)
376 *delim = ':'; /* Restore port */
377
378 host_len = os_strlen(host);
379 path_len = path ? os_strlen(path) : 0;
380 alloc_len = host_len + 1 + 1 + path_len + 1;
381
382 for (rp = result; rp; rp = rp->ai_next) {
383 struct subscr_addr *a;
384
385 /* Limit no. of address to avoid denial of service attack */
386 if (dl_list_len(&s->addr_list) >= MAX_ADDR_PER_SUBSCRIPTION) {
387 wpa_printf(MSG_INFO, "WPS UPnP: subscr_addr_add_url: "
388 "Ignoring excessive addresses");
389 break;
390 }
391
392 a = os_zalloc(sizeof(*a) + alloc_len);
393 if (a == NULL)
394 break;
395 mem = (char *) (a + 1);
396 a->domain_and_port = mem;
397 os_memcpy(mem, host, host_len);
398 mem += host_len + 1;
399 a->path = mem;
400 if (path == NULL || path[0] != '/')
401 *mem++ = '/';
402 if (path)
403 os_memcpy(mem, path, path_len);
404 os_memcpy(&a->saddr, rp->ai_addr, sizeof(a->saddr));
405 a->saddr.sin_port = htons(port);
406
407 dl_list_add(&s->addr_list, &a->list);
408 }
409
410 fail:
411 if (result)
412 freeaddrinfo(result);
413 os_free(scratch_mem);
414 }
415
416
417 /* subscr_addr_list_create -- create list from urls in string.
418 * Each url is enclosed by angle brackets.
419 */
subscr_addr_list_create(struct subscription * s,const char * url_list)420 static void subscr_addr_list_create(struct subscription *s,
421 const char *url_list)
422 {
423 const char *end;
424 wpa_printf(MSG_DEBUG, "WPS UPnP: Parsing URL list '%s'", url_list);
425 for (;;) {
426 while (*url_list == ' ' || *url_list == '\t')
427 url_list++;
428 if (*url_list != '<')
429 break;
430 url_list++;
431 end = os_strchr(url_list, '>');
432 if (end == NULL)
433 break;
434 subscr_addr_add_url(s, url_list, end - url_list);
435 url_list = end + 1;
436 }
437 }
438
439
wpabuf_put_property(struct wpabuf * buf,const char * name,const char * value)440 static void wpabuf_put_property(struct wpabuf *buf, const char *name,
441 const char *value)
442 {
443 wpabuf_put_str(buf, "<e:property>");
444 wpabuf_printf(buf, "<%s>", name);
445 if (value)
446 wpabuf_put_str(buf, value);
447 wpabuf_printf(buf, "</%s>", name);
448 wpabuf_put_str(buf, "</e:property>\n");
449 }
450
451
452 /**
453 * upnp_wps_device_send_event - Queue event messages for subscribers
454 * @sm: WPS UPnP state machine from upnp_wps_device_init()
455 *
456 * This function queues the last WLANEvent to be sent for all currently
457 * subscribed UPnP control points. sm->wlanevent must have been set with the
458 * encoded data before calling this function.
459 */
upnp_wps_device_send_event(struct upnp_wps_device_sm * sm)460 static void upnp_wps_device_send_event(struct upnp_wps_device_sm *sm)
461 {
462 /* Enqueue event message for all subscribers */
463 struct wpabuf *buf; /* holds event message */
464 int buf_size = 0;
465 struct subscription *s, *tmp;
466 /* Actually, utf-8 is the default, but it doesn't hurt to specify it */
467 const char *format_head =
468 "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
469 "<e:propertyset xmlns:e=\"urn:schemas-upnp-org:event-1-0\">\n";
470 const char *format_tail = "</e:propertyset>\n";
471 struct os_reltime now;
472
473 if (dl_list_empty(&sm->subscriptions)) {
474 /* optimize */
475 return;
476 }
477
478 if (os_get_reltime(&now) == 0) {
479 if (now.sec != sm->last_event_sec) {
480 sm->last_event_sec = now.sec;
481 sm->num_events_in_sec = 1;
482 } else {
483 sm->num_events_in_sec++;
484 /*
485 * In theory, this should apply to all WLANEvent
486 * notifications, but EAP messages are of much higher
487 * priority and Probe Request notifications should not
488 * be allowed to drop EAP messages, so only throttle
489 * Probe Request notifications.
490 */
491 if (sm->num_events_in_sec > MAX_EVENTS_PER_SEC &&
492 sm->wlanevent_type ==
493 UPNP_WPS_WLANEVENT_TYPE_PROBE) {
494 wpa_printf(MSG_DEBUG, "WPS UPnP: Throttle "
495 "event notifications (%u seen "
496 "during one second)",
497 sm->num_events_in_sec);
498 return;
499 }
500 }
501 }
502
503 /* Determine buffer size needed first */
504 buf_size += os_strlen(format_head);
505 buf_size += 50 + 2 * os_strlen("WLANEvent");
506 if (sm->wlanevent)
507 buf_size += os_strlen(sm->wlanevent);
508 buf_size += os_strlen(format_tail);
509
510 buf = wpabuf_alloc(buf_size);
511 if (buf == NULL)
512 return;
513 wpabuf_put_str(buf, format_head);
514 wpabuf_put_property(buf, "WLANEvent", sm->wlanevent);
515 wpabuf_put_str(buf, format_tail);
516
517 wpa_printf(MSG_MSGDUMP, "WPS UPnP: WLANEvent message:\n%s",
518 (char *) wpabuf_head(buf));
519
520 dl_list_for_each_safe(s, tmp, &sm->subscriptions, struct subscription,
521 list) {
522 event_add(s, buf,
523 sm->wlanevent_type == UPNP_WPS_WLANEVENT_TYPE_PROBE);
524 }
525
526 wpabuf_free(buf);
527 }
528
529
530 /*
531 * Event subscription (subscriber machines register with us to receive event
532 * messages).
533 * This is the result of an incoming HTTP over TCP SUBSCRIBE request.
534 */
535
536 /* subscription_destroy -- destroy an unlinked subscription
537 * Be sure to unlink first if necessary.
538 */
subscription_destroy(struct subscription * s)539 void subscription_destroy(struct subscription *s)
540 {
541 struct upnp_wps_device_interface *iface;
542 wpa_printf(MSG_DEBUG, "WPS UPnP: Destroy subscription %p", s);
543 subscr_addr_free_all(s);
544 event_delete_all(s);
545 dl_list_for_each(iface, &s->sm->interfaces,
546 struct upnp_wps_device_interface, list)
547 upnp_er_remove_notification(iface->wps->registrar, s);
548 os_free(s);
549 }
550
551
552 /* subscription_list_age -- remove expired subscriptions */
subscription_list_age(struct upnp_wps_device_sm * sm,time_t now)553 static void subscription_list_age(struct upnp_wps_device_sm *sm, time_t now)
554 {
555 struct subscription *s, *tmp;
556 dl_list_for_each_safe(s, tmp, &sm->subscriptions,
557 struct subscription, list) {
558 if (s->timeout_time > now)
559 break;
560 wpa_printf(MSG_DEBUG, "WPS UPnP: Removing aged subscription");
561 dl_list_del(&s->list);
562 subscription_destroy(s);
563 }
564 }
565
566
567 /* subscription_find -- return existing subscription matching uuid, if any
568 * returns NULL if not found
569 */
subscription_find(struct upnp_wps_device_sm * sm,const u8 uuid[UUID_LEN])570 struct subscription * subscription_find(struct upnp_wps_device_sm *sm,
571 const u8 uuid[UUID_LEN])
572 {
573 struct subscription *s;
574 dl_list_for_each(s, &sm->subscriptions, struct subscription, list) {
575 if (os_memcmp(s->uuid, uuid, UUID_LEN) == 0)
576 return s; /* Found match */
577 }
578 return NULL;
579 }
580
581
build_fake_wsc_ack(void)582 static struct wpabuf * build_fake_wsc_ack(void)
583 {
584 struct wpabuf *msg = wpabuf_alloc(100);
585 if (msg == NULL)
586 return NULL;
587 wpabuf_put_u8(msg, UPNP_WPS_WLANEVENT_TYPE_EAP);
588 wpabuf_put_str(msg, "00:00:00:00:00:00");
589 if (wps_build_version(msg) ||
590 wps_build_msg_type(msg, WPS_WSC_ACK)) {
591 wpabuf_free(msg);
592 return NULL;
593 }
594 /* Enrollee Nonce */
595 wpabuf_put_be16(msg, ATTR_ENROLLEE_NONCE);
596 wpabuf_put_be16(msg, WPS_NONCE_LEN);
597 wpabuf_put(msg, WPS_NONCE_LEN);
598 /* Registrar Nonce */
599 wpabuf_put_be16(msg, ATTR_REGISTRAR_NONCE);
600 wpabuf_put_be16(msg, WPS_NONCE_LEN);
601 wpabuf_put(msg, WPS_NONCE_LEN);
602 if (wps_build_wfa_ext(msg, 0, NULL, 0, 0)) {
603 wpabuf_free(msg);
604 return NULL;
605 }
606 return msg;
607 }
608
609
610 /* subscription_first_event -- send format/queue event that is automatically
611 * sent on a new subscription.
612 */
subscription_first_event(struct subscription * s)613 static int subscription_first_event(struct subscription *s)
614 {
615 /*
616 * Actually, utf-8 is the default, but it doesn't hurt to specify it.
617 *
618 * APStatus is apparently a bit set,
619 * 0x1 = configuration change (but is always set?)
620 * 0x10 = ap is locked
621 *
622 * Per UPnP spec, we send out the last value of each variable, even
623 * for WLANEvent, whatever it was.
624 */
625 char *wlan_event;
626 struct wpabuf *buf;
627 int ap_status = 1; /* TODO: add 0x10 if access point is locked */
628 const char *head =
629 "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
630 "<e:propertyset xmlns:e=\"urn:schemas-upnp-org:event-1-0\">\n";
631 const char *tail = "</e:propertyset>\n";
632 char txt[10];
633 int ret;
634
635 if (s->sm->wlanevent == NULL) {
636 /*
637 * There has been no events before the subscription. However,
638 * UPnP device architecture specification requires all the
639 * evented variables to be included, so generate a dummy event
640 * for this particular case using a WSC_ACK and all-zeros
641 * nonces. The ER (UPnP control point) will ignore this, but at
642 * least it will learn that WLANEvent variable will be used in
643 * event notifications in the future.
644 */
645 struct wpabuf *msg;
646 wpa_printf(MSG_DEBUG, "WPS UPnP: Use a fake WSC_ACK as the "
647 "initial WLANEvent");
648 msg = build_fake_wsc_ack();
649 if (msg) {
650 s->sm->wlanevent = (char *)
651 base64_encode(wpabuf_head(msg),
652 wpabuf_len(msg), NULL);
653 wpabuf_free(msg);
654 }
655 }
656
657 wlan_event = s->sm->wlanevent;
658 if (wlan_event == NULL || *wlan_event == '\0') {
659 wpa_printf(MSG_DEBUG, "WPS UPnP: WLANEvent not known for "
660 "initial event message");
661 wlan_event = "";
662 }
663 buf = wpabuf_alloc(500 + os_strlen(wlan_event));
664 if (buf == NULL)
665 return -1;
666
667 wpabuf_put_str(buf, head);
668 wpabuf_put_property(buf, "STAStatus", "1");
669 os_snprintf(txt, sizeof(txt), "%d", ap_status);
670 wpabuf_put_property(buf, "APStatus", txt);
671 if (*wlan_event)
672 wpabuf_put_property(buf, "WLANEvent", wlan_event);
673 wpabuf_put_str(buf, tail);
674
675 ret = event_add(s, buf, 0);
676 if (ret) {
677 wpabuf_free(buf);
678 return ret;
679 }
680 wpabuf_free(buf);
681
682 return 0;
683 }
684
685
686 /**
687 * subscription_start - Remember a UPnP control point to send events to.
688 * @sm: WPS UPnP state machine from upnp_wps_device_init()
689 * @callback_urls: Callback URLs
690 * Returns: %NULL on error, or pointer to new subscription structure.
691 */
subscription_start(struct upnp_wps_device_sm * sm,const char * callback_urls)692 struct subscription * subscription_start(struct upnp_wps_device_sm *sm,
693 const char *callback_urls)
694 {
695 struct subscription *s;
696 time_t now = time(NULL);
697 time_t expire = now + UPNP_SUBSCRIBE_SEC;
698 char str[80];
699
700 /* Get rid of expired subscriptions so we have room */
701 subscription_list_age(sm, now);
702
703 /* If too many subscriptions, remove oldest */
704 if (dl_list_len(&sm->subscriptions) >= MAX_SUBSCRIPTIONS) {
705 s = dl_list_first(&sm->subscriptions, struct subscription,
706 list);
707 if (s) {
708 wpa_printf(MSG_INFO,
709 "WPS UPnP: Too many subscriptions, trashing oldest");
710 dl_list_del(&s->list);
711 subscription_destroy(s);
712 }
713 }
714
715 s = os_zalloc(sizeof(*s));
716 if (s == NULL)
717 return NULL;
718 dl_list_init(&s->addr_list);
719 dl_list_init(&s->event_queue);
720
721 s->sm = sm;
722 s->timeout_time = expire;
723 if (uuid_make(s->uuid) < 0) {
724 subscription_destroy(s);
725 return NULL;
726 }
727 subscr_addr_list_create(s, callback_urls);
728 if (dl_list_empty(&s->addr_list)) {
729 wpa_printf(MSG_DEBUG, "WPS UPnP: No valid callback URLs in "
730 "'%s' - drop subscription", callback_urls);
731 subscription_destroy(s);
732 return NULL;
733 }
734
735 /* Add to end of list, since it has the highest expiration time */
736 dl_list_add_tail(&sm->subscriptions, &s->list);
737 /* Queue up immediate event message (our last event)
738 * as required by UPnP spec.
739 */
740 if (subscription_first_event(s)) {
741 wpa_printf(MSG_INFO, "WPS UPnP: Dropping subscriber due to "
742 "event backlog");
743 dl_list_del(&s->list);
744 subscription_destroy(s);
745 return NULL;
746 }
747 uuid_bin2str(s->uuid, str, sizeof(str));
748 wpa_printf(MSG_DEBUG,
749 "WPS UPnP: Subscription %p (SID %s) started with %s",
750 s, str, callback_urls);
751 /* Schedule sending this */
752 event_send_all_later(sm);
753 return s;
754 }
755
756
757 /* subscription_renew -- find subscription and reset timeout */
subscription_renew(struct upnp_wps_device_sm * sm,const u8 uuid[UUID_LEN])758 struct subscription * subscription_renew(struct upnp_wps_device_sm *sm,
759 const u8 uuid[UUID_LEN])
760 {
761 time_t now = time(NULL);
762 time_t expire = now + UPNP_SUBSCRIBE_SEC;
763 struct subscription *s = subscription_find(sm, uuid);
764 if (s == NULL)
765 return NULL;
766 wpa_printf(MSG_DEBUG, "WPS UPnP: Subscription renewed");
767 dl_list_del(&s->list);
768 s->timeout_time = expire;
769 /* add back to end of list, since it now has highest expiry */
770 dl_list_add_tail(&sm->subscriptions, &s->list);
771 return s;
772 }
773
774
775 /**
776 * upnp_wps_device_send_wlan_event - Event notification
777 * @sm: WPS UPnP state machine from upnp_wps_device_init()
778 * @from_mac_addr: Source (Enrollee) MAC address for the event
779 * @ev_type: Event type
780 * @msg: Event data
781 * Returns: 0 on success, -1 on failure
782 *
783 * Tell external Registrars (UPnP control points) that something happened. In
784 * particular, events include WPS messages from clients that are proxied to
785 * external Registrars.
786 */
upnp_wps_device_send_wlan_event(struct upnp_wps_device_sm * sm,const u8 from_mac_addr[ETH_ALEN],enum upnp_wps_wlanevent_type ev_type,const struct wpabuf * msg)787 int upnp_wps_device_send_wlan_event(struct upnp_wps_device_sm *sm,
788 const u8 from_mac_addr[ETH_ALEN],
789 enum upnp_wps_wlanevent_type ev_type,
790 const struct wpabuf *msg)
791 {
792 int ret = -1;
793 char type[2];
794 const u8 *mac = from_mac_addr;
795 char mac_text[18];
796 u8 *raw = NULL;
797 size_t raw_len;
798 char *val;
799 size_t val_len;
800 int pos = 0;
801
802 if (!sm)
803 goto fail;
804
805 os_snprintf(type, sizeof(type), "%1u", ev_type);
806
807 raw_len = 1 + 17 + (msg ? wpabuf_len(msg) : 0);
808 raw = os_zalloc(raw_len);
809 if (!raw)
810 goto fail;
811
812 *(raw + pos) = (u8) ev_type;
813 pos += 1;
814 os_snprintf(mac_text, sizeof(mac_text), MACSTR, MAC2STR(mac));
815 wpa_printf(MSG_DEBUG, "WPS UPnP: Proxying WLANEvent from %s",
816 mac_text);
817 os_memcpy(raw + pos, mac_text, 17);
818 pos += 17;
819 if (msg) {
820 os_memcpy(raw + pos, wpabuf_head(msg), wpabuf_len(msg));
821 pos += wpabuf_len(msg);
822 }
823 raw_len = pos;
824
825 val = (char *) base64_encode(raw, raw_len, &val_len);
826 if (val == NULL)
827 goto fail;
828
829 os_free(sm->wlanevent);
830 sm->wlanevent = val;
831 sm->wlanevent_type = ev_type;
832 upnp_wps_device_send_event(sm);
833
834 ret = 0;
835
836 fail:
837 os_free(raw);
838
839 return ret;
840 }
841
842
843 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
844 #include <sys/sysctl.h>
845 #include <net/route.h>
846 #include <net/if_dl.h>
847
eth_get(const char * device,u8 ea[ETH_ALEN])848 static int eth_get(const char *device, u8 ea[ETH_ALEN])
849 {
850 struct if_msghdr *ifm;
851 struct sockaddr_dl *sdl;
852 u_char *p, *buf;
853 size_t len;
854 int mib[] = { CTL_NET, AF_ROUTE, 0, AF_LINK, NET_RT_IFLIST, 0 };
855
856 if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0)
857 return -1;
858 if ((buf = os_malloc(len)) == NULL)
859 return -1;
860 if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
861 os_free(buf);
862 return -1;
863 }
864 for (p = buf; p < buf + len; p += ifm->ifm_msglen) {
865 ifm = (struct if_msghdr *)p;
866 sdl = (struct sockaddr_dl *)(ifm + 1);
867 if (ifm->ifm_type != RTM_IFINFO ||
868 (ifm->ifm_addrs & RTA_IFP) == 0)
869 continue;
870 if (sdl->sdl_family != AF_LINK || sdl->sdl_nlen == 0 ||
871 os_memcmp(sdl->sdl_data, device, sdl->sdl_nlen) != 0)
872 continue;
873 os_memcpy(ea, LLADDR(sdl), sdl->sdl_alen);
874 break;
875 }
876 os_free(buf);
877
878 if (p >= buf + len) {
879 errno = ESRCH;
880 return -1;
881 }
882 return 0;
883 }
884 #endif /* __FreeBSD__ || __DragonFly__ */
885
886
887 /**
888 * get_netif_info - Get hw and IP addresses for network device
889 * @net_if: Selected network interface name
890 * @ip_addr: Buffer for returning IP address in network byte order
891 * @ip_addr_text: Buffer for returning a pointer to allocated IP address text
892 * @mac: Buffer for returning MAC address
893 * Returns: 0 on success, -1 on failure
894 */
get_netif_info(const char * net_if,unsigned * ip_addr,char ** ip_addr_text,u8 mac[ETH_ALEN])895 int get_netif_info(const char *net_if, unsigned *ip_addr, char **ip_addr_text,
896 u8 mac[ETH_ALEN])
897 {
898 struct ifreq req;
899 int sock = -1;
900 struct sockaddr_in *addr;
901 struct in_addr in_addr;
902
903 *ip_addr_text = os_zalloc(16);
904 if (*ip_addr_text == NULL)
905 goto fail;
906
907 sock = socket(AF_INET, SOCK_DGRAM, 0);
908 if (sock < 0)
909 goto fail;
910
911 os_strlcpy(req.ifr_name, net_if, sizeof(req.ifr_name));
912 if (ioctl(sock, SIOCGIFADDR, &req) < 0) {
913 wpa_printf(MSG_ERROR, "WPS UPnP: SIOCGIFADDR failed: %d (%s)",
914 errno, strerror(errno));
915 goto fail;
916 }
917 addr = (void *) &req.ifr_addr;
918 *ip_addr = addr->sin_addr.s_addr;
919 in_addr.s_addr = *ip_addr;
920 os_snprintf(*ip_addr_text, 16, "%s", inet_ntoa(in_addr));
921
922 #ifdef __linux__
923 os_strlcpy(req.ifr_name, net_if, sizeof(req.ifr_name));
924 if (ioctl(sock, SIOCGIFHWADDR, &req) < 0) {
925 wpa_printf(MSG_ERROR, "WPS UPnP: SIOCGIFHWADDR failed: "
926 "%d (%s)", errno, strerror(errno));
927 goto fail;
928 }
929 os_memcpy(mac, req.ifr_addr.sa_data, 6);
930 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
931 if (eth_get(net_if, mac) < 0) {
932 wpa_printf(MSG_ERROR, "WPS UPnP: Failed to get MAC address");
933 goto fail;
934 }
935 #else
936 #error MAC address fetch not implemented
937 #endif
938
939 close(sock);
940 return 0;
941
942 fail:
943 if (sock >= 0)
944 close(sock);
945 os_free(*ip_addr_text);
946 *ip_addr_text = NULL;
947 return -1;
948 }
949
950
upnp_wps_free_msearchreply(struct dl_list * head)951 static void upnp_wps_free_msearchreply(struct dl_list *head)
952 {
953 struct advertisement_state_machine *a, *tmp;
954 dl_list_for_each_safe(a, tmp, head, struct advertisement_state_machine,
955 list)
956 msearchreply_state_machine_stop(a);
957 }
958
959
upnp_wps_free_subscriptions(struct dl_list * head,struct wps_registrar * reg)960 static void upnp_wps_free_subscriptions(struct dl_list *head,
961 struct wps_registrar *reg)
962 {
963 struct subscription *s, *tmp;
964 dl_list_for_each_safe(s, tmp, head, struct subscription, list) {
965 if (reg && s->reg != reg)
966 continue;
967 dl_list_del(&s->list);
968 subscription_destroy(s);
969 }
970 }
971
972
973 /**
974 * upnp_wps_device_stop - Stop WPS UPnP operations on an interface
975 * @sm: WPS UPnP state machine from upnp_wps_device_init()
976 */
upnp_wps_device_stop(struct upnp_wps_device_sm * sm)977 static void upnp_wps_device_stop(struct upnp_wps_device_sm *sm)
978 {
979 if (!sm || !sm->started)
980 return;
981
982 wpa_printf(MSG_DEBUG, "WPS UPnP: Stop device");
983 web_listener_stop(sm);
984 ssdp_listener_stop(sm);
985 upnp_wps_free_msearchreply(&sm->msearch_replies);
986 upnp_wps_free_subscriptions(&sm->subscriptions, NULL);
987
988 advertisement_state_machine_stop(sm, 1);
989
990 event_send_stop_all(sm);
991 os_free(sm->wlanevent);
992 sm->wlanevent = NULL;
993 os_free(sm->ip_addr_text);
994 sm->ip_addr_text = NULL;
995 if (sm->multicast_sd >= 0)
996 close(sm->multicast_sd);
997 sm->multicast_sd = -1;
998
999 sm->started = 0;
1000 }
1001
1002
1003 /**
1004 * upnp_wps_device_start - Start WPS UPnP operations on an interface
1005 * @sm: WPS UPnP state machine from upnp_wps_device_init()
1006 * @net_if: Selected network interface name
1007 * Returns: 0 on success, -1 on failure
1008 */
upnp_wps_device_start(struct upnp_wps_device_sm * sm,char * net_if)1009 static int upnp_wps_device_start(struct upnp_wps_device_sm *sm, char *net_if)
1010 {
1011 if (!sm || !net_if)
1012 return -1;
1013
1014 if (sm->started)
1015 upnp_wps_device_stop(sm);
1016
1017 sm->multicast_sd = -1;
1018 sm->ssdp_sd = -1;
1019 sm->started = 1;
1020 sm->advertise_count = 0;
1021
1022 /* Fix up linux multicast handling */
1023 if (add_ssdp_network(net_if))
1024 goto fail;
1025
1026 /* Determine which IP and mac address we're using */
1027 if (get_netif_info(net_if, &sm->ip_addr, &sm->ip_addr_text,
1028 sm->mac_addr)) {
1029 wpa_printf(MSG_INFO, "WPS UPnP: Could not get IP/MAC address "
1030 "for %s. Does it have IP address?", net_if);
1031 goto fail;
1032 }
1033
1034 /* Listen for incoming TCP connections so that others
1035 * can fetch our "xml files" from us.
1036 */
1037 if (web_listener_start(sm))
1038 goto fail;
1039
1040 /* Set up for receiving discovery (UDP) packets */
1041 if (ssdp_listener_start(sm))
1042 goto fail;
1043
1044 /* Set up for sending multicast */
1045 if (ssdp_open_multicast(sm) < 0)
1046 goto fail;
1047
1048 /*
1049 * Broadcast NOTIFY messages to let the world know we exist.
1050 * This is done via a state machine since the messages should not be
1051 * all sent out at once.
1052 */
1053 if (advertisement_state_machine_start(sm))
1054 goto fail;
1055
1056 return 0;
1057
1058 fail:
1059 upnp_wps_device_stop(sm);
1060 return -1;
1061 }
1062
1063
1064 static struct upnp_wps_device_interface *
upnp_wps_get_iface(struct upnp_wps_device_sm * sm,void * priv)1065 upnp_wps_get_iface(struct upnp_wps_device_sm *sm, void *priv)
1066 {
1067 struct upnp_wps_device_interface *iface;
1068 dl_list_for_each(iface, &sm->interfaces,
1069 struct upnp_wps_device_interface, list) {
1070 if (iface->priv == priv)
1071 return iface;
1072 }
1073 return NULL;
1074 }
1075
1076
1077 /**
1078 * upnp_wps_device_deinit - Deinitialize WPS UPnP
1079 * @sm: WPS UPnP state machine from upnp_wps_device_init()
1080 * @priv: External context data that was used in upnp_wps_device_init() call
1081 */
upnp_wps_device_deinit(struct upnp_wps_device_sm * sm,void * priv)1082 void upnp_wps_device_deinit(struct upnp_wps_device_sm *sm, void *priv)
1083 {
1084 struct upnp_wps_device_interface *iface;
1085 struct upnp_wps_peer *peer;
1086
1087 if (!sm)
1088 return;
1089
1090 iface = upnp_wps_get_iface(sm, priv);
1091 if (iface == NULL) {
1092 wpa_printf(MSG_ERROR, "WPS UPnP: Could not find the interface "
1093 "instance to deinit");
1094 return;
1095 }
1096 wpa_printf(MSG_DEBUG, "WPS UPnP: Deinit interface instance %p", iface);
1097 if (dl_list_len(&sm->interfaces) == 1) {
1098 wpa_printf(MSG_DEBUG, "WPS UPnP: Deinitializing last instance "
1099 "- free global device instance");
1100 upnp_wps_device_stop(sm);
1101 } else
1102 upnp_wps_free_subscriptions(&sm->subscriptions,
1103 iface->wps->registrar);
1104 dl_list_del(&iface->list);
1105
1106 while ((peer = dl_list_first(&iface->peers, struct upnp_wps_peer,
1107 list))) {
1108 if (peer->wps)
1109 wps_deinit(peer->wps);
1110 dl_list_del(&peer->list);
1111 os_free(peer);
1112 }
1113 os_free(iface->ctx->ap_pin);
1114 os_free(iface->ctx);
1115 os_free(iface);
1116
1117 if (dl_list_empty(&sm->interfaces)) {
1118 os_free(sm->root_dir);
1119 os_free(sm->desc_url);
1120 os_free(sm);
1121 shared_upnp_device = NULL;
1122 }
1123 }
1124
1125
1126 /**
1127 * upnp_wps_device_init - Initialize WPS UPnP
1128 * @ctx: callback table; we must eventually free it
1129 * @wps: Pointer to longterm WPS context
1130 * @priv: External context data that will be used in callbacks
1131 * @net_if: Selected network interface name
1132 * Returns: WPS UPnP state or %NULL on failure
1133 */
1134 struct upnp_wps_device_sm *
upnp_wps_device_init(struct upnp_wps_device_ctx * ctx,struct wps_context * wps,void * priv,char * net_if)1135 upnp_wps_device_init(struct upnp_wps_device_ctx *ctx, struct wps_context *wps,
1136 void *priv, char *net_if)
1137 {
1138 struct upnp_wps_device_sm *sm;
1139 struct upnp_wps_device_interface *iface;
1140 int start = 0;
1141
1142 iface = os_zalloc(sizeof(*iface));
1143 if (iface == NULL) {
1144 os_free(ctx->ap_pin);
1145 os_free(ctx);
1146 return NULL;
1147 }
1148 wpa_printf(MSG_DEBUG, "WPS UPnP: Init interface instance %p", iface);
1149
1150 dl_list_init(&iface->peers);
1151 iface->ctx = ctx;
1152 iface->wps = wps;
1153 iface->priv = priv;
1154
1155 if (shared_upnp_device) {
1156 wpa_printf(MSG_DEBUG, "WPS UPnP: Share existing device "
1157 "context");
1158 sm = shared_upnp_device;
1159 } else {
1160 wpa_printf(MSG_DEBUG, "WPS UPnP: Initialize device context");
1161 sm = os_zalloc(sizeof(*sm));
1162 if (!sm) {
1163 wpa_printf(MSG_ERROR, "WPS UPnP: upnp_wps_device_init "
1164 "failed");
1165 os_free(iface);
1166 os_free(ctx->ap_pin);
1167 os_free(ctx);
1168 return NULL;
1169 }
1170 shared_upnp_device = sm;
1171
1172 dl_list_init(&sm->msearch_replies);
1173 dl_list_init(&sm->subscriptions);
1174 dl_list_init(&sm->interfaces);
1175 start = 1;
1176 }
1177
1178 dl_list_add(&sm->interfaces, &iface->list);
1179
1180 if (start && upnp_wps_device_start(sm, net_if)) {
1181 upnp_wps_device_deinit(sm, priv);
1182 return NULL;
1183 }
1184
1185
1186 return sm;
1187 }
1188
1189
1190 /**
1191 * upnp_wps_subscribers - Check whether there are any event subscribers
1192 * @sm: WPS UPnP state machine from upnp_wps_device_init()
1193 * Returns: 0 if no subscribers, 1 if subscribers
1194 */
upnp_wps_subscribers(struct upnp_wps_device_sm * sm)1195 int upnp_wps_subscribers(struct upnp_wps_device_sm *sm)
1196 {
1197 return !dl_list_empty(&sm->subscriptions);
1198 }
1199
1200
upnp_wps_set_ap_pin(struct upnp_wps_device_sm * sm,const char * ap_pin)1201 int upnp_wps_set_ap_pin(struct upnp_wps_device_sm *sm, const char *ap_pin)
1202 {
1203 struct upnp_wps_device_interface *iface;
1204 if (sm == NULL)
1205 return 0;
1206
1207 dl_list_for_each(iface, &sm->interfaces,
1208 struct upnp_wps_device_interface, list) {
1209 os_free(iface->ctx->ap_pin);
1210 if (ap_pin) {
1211 iface->ctx->ap_pin = os_strdup(ap_pin);
1212 if (iface->ctx->ap_pin == NULL)
1213 return -1;
1214 } else
1215 iface->ctx->ap_pin = NULL;
1216 }
1217
1218 return 0;
1219 }
1220