hostapd: Update vendor branch to 0.6.10
[dragonfly.git] / contrib / hostapd / src / wps / wps_upnp_ssdp.c
CommitLineData
a875087d
JL
1/*
2 * UPnP SSDP for WPS
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, Jouni Malinen <j@w1.fi>
7 *
8 * See wps_upnp.c for more details on licensing and code history.
9 */
10
11#include "includes.h"
12
13#include <fcntl.h>
14#include <sys/ioctl.h>
15#include <net/route.h>
16
17#include "common.h"
18#include "uuid.h"
19#include "eloop.h"
20#include "wps.h"
21#include "wps_upnp.h"
22#include "wps_upnp_i.h"
23
24#define UPNP_CACHE_SEC (UPNP_CACHE_SEC_MIN + 1) /* cache time we use */
25#define UPNP_CACHE_SEC_MIN 1800 /* min cachable time per UPnP standard */
26#define UPNP_ADVERTISE_REPEAT 2 /* no more than 3 */
27#define MULTICAST_MAX_READ 1600 /* max bytes we'll read for UPD request */
28#define MAX_MSEARCH 20 /* max simultaneous M-SEARCH replies ongoing */
29#define SSDP_TARGET "239.0.0.0"
30#define SSDP_NETMASK "255.0.0.0"
31
32
33/* Check tokens for equality, where tokens consist of letters, digits,
34 * underscore and hyphen, and are matched case insensitive.
35 */
36static int token_eq(const char *s1, const char *s2)
37{
38 int c1;
39 int c2;
40 int end1 = 0;
41 int end2 = 0;
42 for (;;) {
43 c1 = *s1++;
44 c2 = *s2++;
45 if (isalpha(c1) && isupper(c1))
46 c1 = tolower(c1);
47 if (isalpha(c2) && isupper(c2))
48 c2 = tolower(c2);
49 end1 = !(isalnum(c1) || c1 == '_' || c1 == '-');
50 end2 = !(isalnum(c2) || c2 == '_' || c2 == '-');
51 if (end1 || end2 || c1 != c2)
52 break;
53 }
54 return end1 && end2; /* reached end of both words? */
55}
56
57
58/* Return length of token (see above for definition of token) */
59static int token_length(const char *s)
60{
61 const char *begin = s;
62 for (;; s++) {
63 int c = *s;
64 int end = !(isalnum(c) || c == '_' || c == '-');
65 if (end)
66 break;
67 }
68 return s - begin;
69}
70
71
72/* return length of interword separation.
73 * This accepts only spaces/tabs and thus will not traverse a line
74 * or buffer ending.
75 */
76static int word_separation_length(const char *s)
77{
78 const char *begin = s;
79 for (;; s++) {
80 int c = *s;
81 if (c == ' ' || c == '\t')
82 continue;
83 break;
84 }
85 return s - begin;
86}
87
88
89/* No. of chars through (including) end of line */
90static int line_length(const char *l)
91{
92 const char *lp = l;
93 while (*lp && *lp != '\n')
94 lp++;
95 if (*lp == '\n')
96 lp++;
97 return lp - l;
98}
99
100
101/* No. of chars excluding trailing whitespace */
102static int line_length_stripped(const char *l)
103{
104 const char *lp = l + line_length(l);
105 while (lp > l && !isgraph(lp[-1]))
106 lp--;
107 return lp - l;
108}
109
110
111static int str_starts(const char *str, const char *start)
112{
113 return os_strncmp(str, start, os_strlen(start)) == 0;
114}
115
116
117/***************************************************************************
118 * Advertisements.
119 * These are multicast to the world to tell them we are here.
120 * The individual packets are spread out in time to limit loss,
121 * and then after a much longer period of time the whole sequence
122 * is repeated again (for NOTIFYs only).
123 **************************************************************************/
124
125/**
126 * next_advertisement - Build next message and advance the state machine
127 * @a: Advertisement state
128 * @islast: Buffer for indicating whether this is the last message (= 1)
129 * Returns: The new message (caller is responsible for freeing this)
130 *
131 * Note: next_advertisement is shared code with msearchreply_* functions
132 */
133static struct wpabuf *
134next_advertisement(struct advertisement_state_machine *a, int *islast)
135{
136 struct wpabuf *msg;
137 char *NTString = "";
138 char uuid_string[80];
139
140 *islast = 0;
141 uuid_bin2str(a->sm->wps->uuid, uuid_string, sizeof(uuid_string));
142 msg = wpabuf_alloc(800); /* more than big enough */
143 if (msg == NULL)
144 goto fail;
145 switch (a->type) {
146 case ADVERTISE_UP:
147 case ADVERTISE_DOWN:
148 NTString = "NT";
149 wpabuf_put_str(msg, "NOTIFY * HTTP/1.1\r\n");
150 wpabuf_printf(msg, "HOST: %s:%d\r\n",
151 UPNP_MULTICAST_ADDRESS, UPNP_MULTICAST_PORT);
152 wpabuf_printf(msg, "CACHE-CONTROL: max-age=%d\r\n",
153 UPNP_CACHE_SEC);
154 wpabuf_printf(msg, "NTS: %s\r\n",
155 (a->type == ADVERTISE_UP ?
156 "ssdp:alive" : "ssdp:byebye"));
157 break;
158 case MSEARCH_REPLY:
159 NTString = "ST";
160 wpabuf_put_str(msg, "HTTP/1.1 200 OK\r\n");
161 wpabuf_printf(msg, "CACHE-CONTROL: max-age=%d\r\n",
162 UPNP_CACHE_SEC);
163
164 wpabuf_put_str(msg, "DATE: ");
165 format_date(msg);
166 wpabuf_put_str(msg, "\r\n");
167
168 wpabuf_put_str(msg, "EXT:\r\n");
169 break;
170 }
171
172 if (a->type != ADVERTISE_DOWN) {
173 /* Where others may get our XML files from */
174 wpabuf_printf(msg, "LOCATION: http://%s:%d/%s\r\n",
175 a->sm->ip_addr_text, a->sm->web_port,
176 UPNP_WPS_DEVICE_XML_FILE);
177 }
178
179 /* The SERVER line has three comma-separated fields:
180 * operating system / version
181 * upnp version
182 * software package / version
183 * However, only the UPnP version is really required, the
184 * others can be place holders... for security reasons
185 * it is better to NOT provide extra information.
186 */
187 wpabuf_put_str(msg, "SERVER: Unspecified, UPnP/1.0, Unspecified\r\n");
188
189 switch (a->state / UPNP_ADVERTISE_REPEAT) {
190 case 0:
191 wpabuf_printf(msg, "%s: upnp:rootdevice\r\n", NTString);
192 wpabuf_printf(msg, "USN: uuid:%s::upnp:rootdevice\r\n",
193 uuid_string);
194 break;
195 case 1:
196 wpabuf_printf(msg, "%s: uuid:%s\r\n", NTString, uuid_string);
197 wpabuf_printf(msg, "USN: uuid:%s\r\n", uuid_string);
198 break;
199 case 2:
200 wpabuf_printf(msg, "%s: urn:schemas-wifialliance-org:device:"
201 "WFADevice:1\r\n", NTString);
202 wpabuf_printf(msg, "USN: uuid:%s::urn:schemas-wifialliance-"
203 "org:device:WFADevice:1\r\n", uuid_string);
204 break;
205 case 3:
206 wpabuf_printf(msg, "%s: urn:schemas-wifialliance-org:service:"
207 "WFAWLANConfig:1\r\n", NTString);
208 wpabuf_printf(msg, "USN: uuid:%s::urn:schemas-wifialliance-"
209 "org:service:WFAWLANConfig:1\r\n", uuid_string);
210 break;
211 }
212 wpabuf_put_str(msg, "\r\n");
213
214 if (a->state + 1 >= 4 * UPNP_ADVERTISE_REPEAT)
215 *islast = 1;
216
217 return msg;
218
219fail:
220 wpabuf_free(msg);
221 return NULL;
222}
223
224
225static void advertisement_state_machine_handler(void *eloop_data,
226 void *user_ctx);
227
228
229/**
230 * advertisement_state_machine_stop - Stop SSDP advertisements
231 * @sm: WPS UPnP state machine from upnp_wps_device_init()
232 * @send_byebye: Send byebye advertisement messages immediately
233 */
234void advertisement_state_machine_stop(struct upnp_wps_device_sm *sm,
235 int send_byebye)
236{
237 struct advertisement_state_machine *a = &sm->advertisement;
238 int islast = 0;
239 struct wpabuf *msg;
240 struct sockaddr_in dest;
241
242 eloop_cancel_timeout(advertisement_state_machine_handler, NULL, sm);
243 if (!send_byebye || sm->multicast_sd < 0)
244 return;
245
246 a->type = ADVERTISE_DOWN;
247 a->state = 0;
248 a->sm = sm;
249
250 os_memset(&dest, 0, sizeof(dest));
251 dest.sin_family = AF_INET;
252 dest.sin_addr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS);
253 dest.sin_port = htons(UPNP_MULTICAST_PORT);
254
255 while (!islast) {
256 msg = next_advertisement(a, &islast);
257 if (msg == NULL)
258 break;
259 if (sendto(sm->multicast_sd, wpabuf_head(msg), wpabuf_len(msg),
260 0, (struct sockaddr *) &dest, sizeof(dest)) < 0) {
261 wpa_printf(MSG_INFO, "WPS UPnP: Advertisement sendto "
262 "failed: %d (%s)", errno, strerror(errno));
263 }
264 wpabuf_free(msg);
265 a->state++;
266 }
267}
268
269
270static void advertisement_state_machine_handler(void *eloop_data,
271 void *user_ctx)
272{
273 struct upnp_wps_device_sm *sm = user_ctx;
274 struct advertisement_state_machine *a = &sm->advertisement;
275 struct wpabuf *msg;
276 int next_timeout_msec = 100;
277 int next_timeout_sec = 0;
278 struct sockaddr_in dest;
279 int islast = 0;
280
281 /*
282 * Each is sent twice (in case lost) w/ 100 msec delay between;
283 * spec says no more than 3 times.
284 * One pair for rootdevice, one pair for uuid, and a pair each for
285 * each of the two urns.
286 * The entire sequence must be repeated before cache control timeout
287 * (which is min 1800 seconds),
288 * recommend random portion of half of the advertised cache control age
289 * to ensure against loss... perhaps 1800/4 + rand*1800/4 ?
290 * Delay random interval < 100 msec prior to initial sending.
291 * TTL of 4
292 */
293
294 wpa_printf(MSG_MSGDUMP, "WPS UPnP: Advertisement state=%d", a->state);
295 msg = next_advertisement(a, &islast);
296 if (msg == NULL)
297 return;
298
299 os_memset(&dest, 0, sizeof(dest));
300 dest.sin_family = AF_INET;
301 dest.sin_addr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS);
302 dest.sin_port = htons(UPNP_MULTICAST_PORT);
303
304 if (sendto(sm->multicast_sd, wpabuf_head(msg), wpabuf_len(msg), 0,
305 (struct sockaddr *) &dest, sizeof(dest)) == -1) {
306 wpa_printf(MSG_ERROR, "WPS UPnP: Advertisement sendto failed:"
307 "%d (%s)", errno, strerror(errno));
308 next_timeout_msec = 0;
309 next_timeout_sec = 10; /* ... later */
310 } else if (islast) {
311 a->state = 0; /* wrap around */
312 if (a->type == ADVERTISE_DOWN) {
313 wpa_printf(MSG_DEBUG, "WPS UPnP: ADVERTISE_DOWN->UP");
314 a->type = ADVERTISE_UP;
315 /* do it all over again right away */
316 } else {
317 u16 r;
318 /*
319 * Start over again after a long timeout
320 * (see notes above)
321 */
322 next_timeout_msec = 0;
323 os_get_random((void *) &r, sizeof(r));
324 next_timeout_sec = UPNP_CACHE_SEC / 4 +
325 (((UPNP_CACHE_SEC / 4) * r) >> 16);
326 sm->advertise_count++;
327 wpa_printf(MSG_DEBUG, "WPS UPnP: ADVERTISE_UP (#%u); "
328 "next in %d sec",
329 sm->advertise_count, next_timeout_sec);
330 }
331 } else {
332 a->state++;
333 }
334
335 wpabuf_free(msg);
336
337 eloop_register_timeout(next_timeout_sec, next_timeout_msec,
338 advertisement_state_machine_handler, NULL, sm);
339}
340
341
342/**
343 * advertisement_state_machine_start - Start SSDP advertisements
344 * @sm: WPS UPnP state machine from upnp_wps_device_init()
345 * Returns: 0 on success, -1 on failure
346 */
347int advertisement_state_machine_start(struct upnp_wps_device_sm *sm)
348{
349 struct advertisement_state_machine *a = &sm->advertisement;
350 int next_timeout_msec;
351
352 advertisement_state_machine_stop(sm, 0);
353
354 /*
355 * Start out advertising down, this automatically switches
356 * to advertising up which signals our restart.
357 */
358 a->type = ADVERTISE_DOWN;
359 a->state = 0;
360 a->sm = sm;
361 /* (other fields not used here) */
362
363 /* First timeout should be random interval < 100 msec */
364 next_timeout_msec = (100 * (os_random() & 0xFF)) >> 8;
365 return eloop_register_timeout(0, next_timeout_msec,
366 advertisement_state_machine_handler,
367 NULL, sm);
368}
369
370
371/***************************************************************************
372 * M-SEARCH replies
373 * These are very similar to the multicast advertisements, with some
374 * small changes in data content; and they are sent (UDP) to a specific
375 * unicast address instead of multicast.
376 * They are sent in response to a UDP M-SEARCH packet.
377 **************************************************************************/
378
379static void msearchreply_state_machine_handler(void *eloop_data,
380 void *user_ctx);
381
382
383/**
384 * msearchreply_state_machine_stop - Stop M-SEARCH reply state machine
385 * @a: Selected advertisement/reply state
386 */
387void msearchreply_state_machine_stop(struct advertisement_state_machine *a)
388{
389 struct upnp_wps_device_sm *sm = a->sm;
390 wpa_printf(MSG_DEBUG, "WPS UPnP: M-SEARCH stop");
391 if (a->next == a) {
392 sm->msearch_replies = NULL;
393 } else {
394 if (sm->msearch_replies == a)
395 sm->msearch_replies = a->next;
396 a->next->prev = a->prev;
397 a->prev->next = a->next;
398 }
399 os_free(a);
400 sm->n_msearch_replies--;
401}
402
403
404static void msearchreply_state_machine_handler(void *eloop_data,
405 void *user_ctx)
406{
407 struct advertisement_state_machine *a = user_ctx;
408 struct upnp_wps_device_sm *sm = a->sm;
409 struct wpabuf *msg;
410 int next_timeout_msec = 100;
411 int next_timeout_sec = 0;
412 int islast = 0;
413
414 /*
415 * Each response is sent twice (in case lost) w/ 100 msec delay
416 * between; spec says no more than 3 times.
417 * One pair for rootdevice, one pair for uuid, and a pair each for
418 * each of the two urns.
419 */
420
421 /* TODO: should only send the requested response types */
422
423 wpa_printf(MSG_MSGDUMP, "WPS UPnP: M-SEARCH reply state=%d (%s:%d)",
424 a->state, inet_ntoa(a->client.sin_addr),
425 ntohs(a->client.sin_port));
426 msg = next_advertisement(a, &islast);
427 if (msg == NULL)
428 return;
429
430 /*
431 * Send it on the multicast socket to avoid having to set up another
432 * socket.
433 */
434 if (sendto(sm->multicast_sd, wpabuf_head(msg), wpabuf_len(msg), 0,
435 (struct sockaddr *) &a->client, sizeof(a->client)) < 0) {
436 wpa_printf(MSG_DEBUG, "WPS UPnP: M-SEARCH reply sendto "
437 "errno %d (%s) for %s:%d",
438 errno, strerror(errno),
439 inet_ntoa(a->client.sin_addr),
440 ntohs(a->client.sin_port));
441 /* Ignore error and hope for the best */
442 }
443 wpabuf_free(msg);
444 if (islast) {
445 wpa_printf(MSG_DEBUG, "WPS UPnP: M-SEARCH reply done");
446 msearchreply_state_machine_stop(a);
447 return;
448 }
449 a->state++;
450
451 wpa_printf(MSG_MSGDUMP, "WPS UPnP: M-SEARCH reply in %d.%03d sec",
452 next_timeout_sec, next_timeout_msec);
453 eloop_register_timeout(next_timeout_sec, next_timeout_msec,
454 msearchreply_state_machine_handler, sm, a);
455}
456
457
458/**
459 * msearchreply_state_machine_start - Reply to M-SEARCH discovery request
460 * @sm: WPS UPnP state machine from upnp_wps_device_init()
461 * @client: Client address
462 * @mx: Maximum delay in seconds
463 *
464 * Use TTL of 4 (this was done when socket set up).
465 * A response should be given in randomized portion of min(MX,120) seconds
466 *
467 * UPnP-arch-DeviceArchitecture, 1.2.3:
468 * To be found, a device must send a UDP response to the source IP address and
469 * port that sent the request to the multicast channel. Devices respond if the
470 * ST header of the M-SEARCH request is "ssdp:all", "upnp:rootdevice", "uuid:"
471 * followed by a UUID that exactly matches one advertised by the device.
472 */
473static void msearchreply_state_machine_start(struct upnp_wps_device_sm *sm,
474 struct sockaddr_in *client,
475 int mx)
476{
477 struct advertisement_state_machine *a;
478 int next_timeout_sec;
479 int next_timeout_msec;
480
481 wpa_printf(MSG_DEBUG, "WPS UPnP: M-SEARCH reply start (%d "
482 "outstanding)", sm->n_msearch_replies);
483 if (sm->n_msearch_replies >= MAX_MSEARCH) {
484 wpa_printf(MSG_INFO, "WPS UPnP: Too many outstanding "
485 "M-SEARCH replies");
486 return;
487 }
488
489 a = os_zalloc(sizeof(*a));
490 if (a == NULL)
491 return;
492 a->type = MSEARCH_REPLY;
493 a->state = 0;
494 a->sm = sm;
495 os_memcpy(&a->client, client, sizeof(*client));
496 /* Wait time depending on MX value */
497 next_timeout_msec = (1000 * mx * (os_random() & 0xFF)) >> 8;
498 next_timeout_sec = next_timeout_msec / 1000;
499 next_timeout_msec = next_timeout_msec % 1000;
500 if (eloop_register_timeout(next_timeout_sec, next_timeout_msec,
501 msearchreply_state_machine_handler, sm,
502 a)) {
503 /* No way to recover (from malloc failure) */
504 goto fail;
505 }
506 /* Remember for future cleanup */
507 if (sm->msearch_replies) {
508 a->next = sm->msearch_replies;
509 a->prev = a->next->prev;
510 a->prev->next = a;
511 a->next->prev = a;
512 } else {
513 sm->msearch_replies = a->next = a->prev = a;
514 }
515 sm->n_msearch_replies++;
516 return;
517
518fail:
519 wpa_printf(MSG_INFO, "WPS UPnP: M-SEARCH reply failure!");
520 eloop_cancel_timeout(msearchreply_state_machine_handler, sm, a);
521 os_free(a);
522}
523
524
525/**
526 * ssdp_parse_msearch - Process a received M-SEARCH
527 * @sm: WPS UPnP state machine from upnp_wps_device_init()
528 * @client: Client address
529 * @data: NULL terminated M-SEARCH message
530 *
531 * Given that we have received a header w/ M-SEARCH, act upon it
532 *
533 * Format of M-SEARCH (case insensitive!):
534 *
535 * First line must be:
536 * M-SEARCH * HTTP/1.1
537 * Other lines in arbitrary order:
538 * HOST:239.255.255.250:1900
539 * ST:<varies -- must match>
540 * MAN:"ssdp:discover"
541 * MX:<varies>
542 *
543 * It should be noted that when Microsoft Vista is still learning its IP
544 * address, it sends out host lines like: HOST:[FF02::C]:1900
545 */
546static void ssdp_parse_msearch(struct upnp_wps_device_sm *sm,
547 struct sockaddr_in *client, const char *data)
548{
549 const char *start = data;
550 const char *end;
551 int got_host = 0;
552 int got_st = 0, st_match = 0;
553 int got_man = 0;
554 int got_mx = 0;
555 int mx = 0;
556
557 /*
558 * Skip first line M-SEARCH * HTTP/1.1
559 * (perhaps we should check remainder of the line for syntax)
560 */
561 data += line_length(data);
562
563 /* Parse remaining lines */
564 for (; *data != '\0'; data += line_length(data)) {
565 end = data + line_length_stripped(data);
566 if (token_eq(data, "host")) {
567 /* The host line indicates who the packet
568 * is addressed to... but do we really care?
569 * Note that Microsoft sometimes does funny
570 * stuff with the HOST: line.
571 */
572#if 0 /* could be */
573 data += token_length(data);
574 data += word_separation_length(data);
575 if (*data != ':')
576 goto bad;
577 data++;
578 data += word_separation_length(data);
579 /* UPNP_MULTICAST_ADDRESS */
580 if (!str_starts(data, "239.255.255.250"))
581 goto bad;
582 data += os_strlen("239.255.255.250");
583 if (*data == ':') {
584 if (!str_starts(data, ":1900"))
585 goto bad;
586 }
587#endif /* could be */
588 got_host = 1;
589 continue;
590 } else if (token_eq(data, "st")) {
591 /* There are a number of forms; we look
592 * for one that matches our case.
593 */
594 got_st = 1;
595 data += token_length(data);
596 data += word_separation_length(data);
597 if (*data != ':')
598 continue;
599 data++;
600 data += word_separation_length(data);
601 if (str_starts(data, "ssdp:all")) {
602 st_match = 1;
603 continue;
604 }
605 if (str_starts(data, "upnp:rootdevice")) {
606 st_match = 1;
607 continue;
608 }
609 if (str_starts(data, "uuid:")) {
610 char uuid_string[80];
611 data += os_strlen("uuid:");
612 uuid_bin2str(sm->wps->uuid, uuid_string,
613 sizeof(uuid_string));
614 if (str_starts(data, uuid_string))
615 st_match = 1;
616 continue;
617 }
618#if 0
619 /* FIX: should we really reply to IGD string? */
620 if (str_starts(data, "urn:schemas-upnp-org:device:"
621 "InternetGatewayDevice:1")) {
622 st_match = 1;
623 continue;
624 }
625#endif
626 if (str_starts(data, "urn:schemas-wifialliance-org:"
627 "service:WFAWLANConfig:1")) {
628 st_match = 1;
629 continue;
630 }
631 if (str_starts(data, "urn:schemas-wifialliance-org:"
632 "device:WFADevice:1")) {
633 st_match = 1;
634 continue;
635 }
636 continue;
637 } else if (token_eq(data, "man")) {
638 data += token_length(data);
639 data += word_separation_length(data);
640 if (*data != ':')
641 continue;
642 data++;
643 data += word_separation_length(data);
644 if (!str_starts(data, "\"ssdp:discover\"")) {
645 wpa_printf(MSG_DEBUG, "WPS UPnP: Unexpected "
646 "M-SEARCH man-field");
647 goto bad;
648 }
649 got_man = 1;
650 continue;
651 } else if (token_eq(data, "mx")) {
652 data += token_length(data);
653 data += word_separation_length(data);
654 if (*data != ':')
655 continue;
656 data++;
657 data += word_separation_length(data);
658 mx = atol(data);
659 got_mx = 1;
660 continue;
661 }
662 /* ignore anything else */
663 }
664 if (!got_host || !got_st || !got_man || !got_mx || mx < 0) {
665 wpa_printf(MSG_DEBUG, "WPS UPnP: Invalid M-SEARCH: %d %d %d "
666 "%d mx=%d", got_host, got_st, got_man, got_mx, mx);
667 goto bad;
668 }
669 if (!st_match) {
670 wpa_printf(MSG_DEBUG, "WPS UPnP: Ignored M-SEARCH (no ST "
671 "match)");
672 return;
673 }
674 if (mx > 120)
675 mx = 120; /* UPnP-arch-DeviceArchitecture, 1.2.3 */
676 msearchreply_state_machine_start(sm, client, mx);
677 return;
678
679bad:
680 wpa_printf(MSG_INFO, "WPS UPnP: Failed to parse M-SEARCH");
681 wpa_printf(MSG_MSGDUMP, "WPS UPnP: M-SEARCH data:\n%s", start);
682}
683
684
685/* Listening for (UDP) discovery (M-SEARCH) packets */
686
687/**
688 * ssdp_listener_stop - Stop SSDP listered
689 * @sm: WPS UPnP state machine from upnp_wps_device_init()
690 *
691 * This function stops the SSDP listerner that was started by calling
692 * ssdp_listener_start().
693 */
694void ssdp_listener_stop(struct upnp_wps_device_sm *sm)
695{
696 if (sm->ssdp_sd_registered) {
697 eloop_unregister_sock(sm->ssdp_sd, EVENT_TYPE_READ);
698 sm->ssdp_sd_registered = 0;
699 }
700
701 if (sm->ssdp_sd != -1) {
702 close(sm->ssdp_sd);
703 sm->ssdp_sd = -1;
704 }
705
706 eloop_cancel_timeout(msearchreply_state_machine_handler, sm,
707 ELOOP_ALL_CTX);
708}
709
710
711static void ssdp_listener_handler(int sd, void *eloop_ctx, void *sock_ctx)
712{
713 struct upnp_wps_device_sm *sm = sock_ctx;
714 struct sockaddr_in addr; /* client address */
715 socklen_t addr_len;
716 int nread;
717 char buf[MULTICAST_MAX_READ], *pos;
718
719 addr_len = sizeof(addr);
720 nread = recvfrom(sm->ssdp_sd, buf, sizeof(buf) - 1, 0,
721 (struct sockaddr *) &addr, &addr_len);
722 if (nread <= 0)
723 return;
724 buf[nread] = '\0'; /* need null termination for algorithm */
725
726 if (str_starts(buf, "NOTIFY ")) {
727 /*
728 * Silently ignore NOTIFYs to avoid filling debug log with
729 * unwanted messages.
730 */
731 return;
732 }
733
734 pos = os_strchr(buf, '\n');
735 if (pos)
736 *pos = '\0';
737 wpa_printf(MSG_MSGDUMP, "WPS UPnP: Received SSDP packet from %s:%d: "
738 "%s", inet_ntoa(addr.sin_addr), ntohs(addr.sin_port), buf);
739 if (pos)
740 *pos = '\n';
741
742 /* Parse first line */
743 if (os_strncasecmp(buf, "M-SEARCH", os_strlen("M-SEARCH")) == 0 &&
744 !isgraph(buf[strlen("M-SEARCH")])) {
745 ssdp_parse_msearch(sm, &addr, buf);
746 return;
747 }
748
749 /* Ignore anything else */
750}
751
752
753/**
754 * ssdp_listener_start - Set up for receiving discovery (UDP) packets
755 * @sm: WPS UPnP state machine from upnp_wps_device_init()
756 * Returns: 0 on success, -1 on failure
757 *
758 * The SSDP listerner is stopped by calling ssdp_listener_stop().
759 */
760int ssdp_listener_start(struct upnp_wps_device_sm *sm)
761{
762 int sd = -1;
763 struct sockaddr_in addr;
764 struct ip_mreq mcast_addr;
765 int on = 1;
766 /* per UPnP spec, keep IP packet time to live (TTL) small */
767 unsigned char ttl = 4;
768
769 sm->ssdp_sd = sd = socket(AF_INET, SOCK_DGRAM, 0);
770 if (sd < 0)
771 goto fail;
772 if (fcntl(sd, F_SETFL, O_NONBLOCK) != 0)
773 goto fail;
774 if (setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)))
775 goto fail;
776 os_memset(&addr, 0, sizeof(addr));
777 addr.sin_family = AF_INET;
778 addr.sin_addr.s_addr = htonl(INADDR_ANY);
779 addr.sin_port = htons(UPNP_MULTICAST_PORT);
780 if (bind(sd, (struct sockaddr *) &addr, sizeof(addr)))
781 goto fail;
782 os_memset(&mcast_addr, 0, sizeof(mcast_addr));
783 mcast_addr.imr_interface.s_addr = htonl(INADDR_ANY);
784 mcast_addr.imr_multiaddr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS);
785 if (setsockopt(sd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
786 (char *) &mcast_addr, sizeof(mcast_addr)))
787 goto fail;
788 if (setsockopt(sd, IPPROTO_IP, IP_MULTICAST_TTL,
789 &ttl, sizeof(ttl)))
790 goto fail;
791 if (eloop_register_sock(sd, EVENT_TYPE_READ, ssdp_listener_handler,
792 NULL, sm))
793 goto fail;
794 sm->ssdp_sd_registered = 1;
795 return 0;
796
797fail:
798 /* Error */
799 wpa_printf(MSG_ERROR, "WPS UPnP: ssdp_listener_start failed");
800 ssdp_listener_stop(sm);
801 return -1;
802}
803
804
805/**
806 * add_ssdp_network - Add routing entry for SSDP
807 * @net_if: Selected network interface name
808 * Returns: 0 on success, -1 on failure
809 *
810 * This function assures that the multicast address will be properly
811 * handled by Linux networking code (by a modification to routing tables).
812 * This must be done per network interface. It really only needs to be done
813 * once after booting up, but it does not hurt to call this more frequently
814 * "to be safe".
815 */
816int add_ssdp_network(char *net_if)
817{
818#ifdef __linux__
819 int ret = -1;
820 int sock = -1;
821 struct rtentry rt;
822 struct sockaddr_in *sin;
823
824 if (!net_if)
825 goto fail;
826
827 os_memset(&rt, 0, sizeof(rt));
828 sock = socket(AF_INET, SOCK_DGRAM, 0);
829 if (sock < 0)
830 goto fail;
831
832 rt.rt_dev = net_if;
833 sin = aliasing_hide_typecast(&rt.rt_dst, struct sockaddr_in);
834 sin->sin_family = AF_INET;
835 sin->sin_port = 0;
836 sin->sin_addr.s_addr = inet_addr(SSDP_TARGET);
837 sin = aliasing_hide_typecast(&rt.rt_genmask, struct sockaddr_in);
838 sin->sin_family = AF_INET;
839 sin->sin_port = 0;
840 sin->sin_addr.s_addr = inet_addr(SSDP_NETMASK);
841 rt.rt_flags = RTF_UP;
842 if (ioctl(sock, SIOCADDRT, &rt) < 0) {
843 if (errno == EPERM) {
844 wpa_printf(MSG_DEBUG, "add_ssdp_network: No "
845 "permissions to add routing table entry");
846 /* Continue to allow testing as non-root */
847 } else if (errno != EEXIST) {
848 wpa_printf(MSG_INFO, "add_ssdp_network() ioctl errno "
849 "%d (%s)", errno, strerror(errno));
850 goto fail;
851 }
852 }
853
854 ret = 0;
855
856fail:
857 if (sock >= 0)
858 close(sock);
859
860 return ret;
861#else /* __linux__ */
862 return 0;
863#endif /* __linux__ */
864}
865
866
867/**
868 * ssdp_open_multicast - Open socket for sending multicast SSDP messages
869 * @sm: WPS UPnP state machine from upnp_wps_device_init()
870 * Returns: 0 on success, -1 on failure
871 */
872int ssdp_open_multicast(struct upnp_wps_device_sm *sm)
873{
874 int sd = -1;
875 /* per UPnP-arch-DeviceArchitecture, 1. Discovery, keep IP packet
876 * time to live (TTL) small */
877 unsigned char ttl = 4;
878
879 sm->multicast_sd = sd = socket(AF_INET, SOCK_DGRAM, 0);
880 if (sd < 0)
881 return -1;
882
883#if 0 /* maybe ok if we sometimes block on writes */
884 if (fcntl(sd, F_SETFL, O_NONBLOCK) != 0)
885 return -1;
886#endif
887
888 if (setsockopt(sd, IPPROTO_IP, IP_MULTICAST_IF,
889 &sm->ip_addr, sizeof(sm->ip_addr)))
890 return -1;
891 if (setsockopt(sd, IPPROTO_IP, IP_MULTICAST_TTL,
892 &ttl, sizeof(ttl)))
893 return -1;
894
895#if 0 /* not needed, because we don't receive using multicast_sd */
896 {
897 struct ip_mreq mreq;
898 mreq.imr_multiaddr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS);
899 mreq.imr_interface.s_addr = sm->ip_addr;
900 wpa_printf(MSG_DEBUG, "WPS UPnP: Multicast addr 0x%x if addr "
901 "0x%x",
902 mreq.imr_multiaddr.s_addr,
903 mreq.imr_interface.s_addr);
904 if (setsockopt(sd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq,
905 sizeof(mreq))) {
906 wpa_printf(MSG_ERROR,
907 "WPS UPnP: setsockopt "
908 "IP_ADD_MEMBERSHIP errno %d (%s)",
909 errno, strerror(errno));
910 return -1;
911 }
912 }
913#endif /* not needed */
914
915 /*
916 * TODO: What about IP_MULTICAST_LOOP? It seems to be on by default?
917 * which aids debugging I suppose but isn't really necessary?
918 */
919
920 return 0;
921}