Disconnect hostapd from building in base
[dragonfly.git] / contrib / hostapd / src / wps / wps_upnp_ssdp.c
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) 2009-2013, 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 #ifdef __linux__
17 #include <net/if.h>
18 #endif /* __linux__ */
19
20 #include "common.h"
21 #include "uuid.h"
22 #include "eloop.h"
23 #include "wps.h"
24 #include "wps_upnp.h"
25 #include "wps_upnp_i.h"
26
27 #define UPNP_CACHE_SEC (UPNP_CACHE_SEC_MIN + 1) /* cache time we use */
28 #define UPNP_CACHE_SEC_MIN 1800 /* min cachable time per UPnP standard */
29 #define UPNP_ADVERTISE_REPEAT 2 /* no more than 3 */
30 #define MAX_MSEARCH 20          /* max simultaneous M-SEARCH replies ongoing */
31 #define SSDP_TARGET  "239.0.0.0"
32 #define SSDP_NETMASK "255.0.0.0"
33
34
35 /* Check tokens for equality, where tokens consist of letters, digits,
36  * underscore and hyphen, and are matched case insensitive.
37  */
38 static int token_eq(const char *s1, const char *s2)
39 {
40         int c1;
41         int c2;
42         int end1 = 0;
43         int end2 = 0;
44         for (;;) {
45                 c1 = *s1++;
46                 c2 = *s2++;
47                 if (isalpha(c1) && isupper(c1))
48                         c1 = tolower(c1);
49                 if (isalpha(c2) && isupper(c2))
50                         c2 = tolower(c2);
51                 end1 = !(isalnum(c1) || c1 == '_' || c1 == '-');
52                 end2 = !(isalnum(c2) || c2 == '_' || c2 == '-');
53                 if (end1 || end2 || c1 != c2)
54                         break;
55         }
56         return end1 && end2; /* reached end of both words? */
57 }
58
59
60 /* Return length of token (see above for definition of token) */
61 static int token_length(const char *s)
62 {
63         const char *begin = s;
64         for (;; s++) {
65                 int c = *s;
66                 int end = !(isalnum(c) || c == '_' || c == '-');
67                 if (end)
68                         break;
69         }
70         return s - begin;
71 }
72
73
74 /* return length of interword separation.
75  * This accepts only spaces/tabs and thus will not traverse a line
76  * or buffer ending.
77  */
78 static int word_separation_length(const char *s)
79 {
80         const char *begin = s;
81         for (;; s++) {
82                 int c = *s;
83                 if (c == ' ' || c == '\t')
84                         continue;
85                 break;
86         }
87         return s - begin;
88 }
89
90
91 /* No. of chars through (including) end of line */
92 static int line_length(const char *l)
93 {
94         const char *lp = l;
95         while (*lp && *lp != '\n')
96                 lp++;
97         if (*lp == '\n')
98                 lp++;
99         return lp - l;
100 }
101
102
103 static int str_starts(const char *str, const char *start)
104 {
105         return os_strncmp(str, start, os_strlen(start)) == 0;
106 }
107
108
109 /***************************************************************************
110  * Advertisements.
111  * These are multicast to the world to tell them we are here.
112  * The individual packets are spread out in time to limit loss,
113  * and then after a much longer period of time the whole sequence
114  * is repeated again (for NOTIFYs only).
115  **************************************************************************/
116
117 /**
118  * next_advertisement - Build next message and advance the state machine
119  * @a: Advertisement state
120  * @islast: Buffer for indicating whether this is the last message (= 1)
121  * Returns: The new message (caller is responsible for freeing this)
122  *
123  * Note: next_advertisement is shared code with msearchreply_* functions
124  */
125 static struct wpabuf *
126 next_advertisement(struct upnp_wps_device_sm *sm,
127                    struct advertisement_state_machine *a, int *islast)
128 {
129         struct wpabuf *msg;
130         char *NTString = "";
131         char uuid_string[80];
132         struct upnp_wps_device_interface *iface;
133
134         *islast = 0;
135         iface = dl_list_first(&sm->interfaces,
136                               struct upnp_wps_device_interface, list);
137         uuid_bin2str(iface->wps->uuid, uuid_string, sizeof(uuid_string));
138         msg = wpabuf_alloc(800); /* more than big enough */
139         if (msg == NULL)
140                 goto fail;
141         switch (a->type) {
142         case ADVERTISE_UP:
143         case ADVERTISE_DOWN:
144                 NTString = "NT";
145                 wpabuf_put_str(msg, "NOTIFY * HTTP/1.1\r\n");
146                 wpabuf_printf(msg, "HOST: %s:%d\r\n",
147                               UPNP_MULTICAST_ADDRESS, UPNP_MULTICAST_PORT);
148                 wpabuf_printf(msg, "CACHE-CONTROL: max-age=%d\r\n",
149                               UPNP_CACHE_SEC);
150                 wpabuf_printf(msg, "NTS: %s\r\n",
151                               (a->type == ADVERTISE_UP ?
152                                "ssdp:alive" : "ssdp:byebye"));
153                 break;
154         case MSEARCH_REPLY:
155                 NTString = "ST";
156                 wpabuf_put_str(msg, "HTTP/1.1 200 OK\r\n");
157                 wpabuf_printf(msg, "CACHE-CONTROL: max-age=%d\r\n",
158                               UPNP_CACHE_SEC);
159
160                 wpabuf_put_str(msg, "DATE: ");
161                 format_date(msg);
162                 wpabuf_put_str(msg, "\r\n");
163
164                 wpabuf_put_str(msg, "EXT:\r\n");
165                 break;
166         }
167
168         if (a->type != ADVERTISE_DOWN) {
169                 /* Where others may get our XML files from */
170                 wpabuf_printf(msg, "LOCATION: http://%s:%d/%s\r\n",
171                               sm->ip_addr_text, sm->web_port,
172                               UPNP_WPS_DEVICE_XML_FILE);
173         }
174
175         /* The SERVER line has three comma-separated fields:
176          *      operating system / version
177          *      upnp version
178          *      software package / version
179          * However, only the UPnP version is really required, the
180          * others can be place holders... for security reasons
181          * it is better to NOT provide extra information.
182          */
183         wpabuf_put_str(msg, "SERVER: Unspecified, UPnP/1.0, Unspecified\r\n");
184
185         switch (a->state / UPNP_ADVERTISE_REPEAT) {
186         case 0:
187                 wpabuf_printf(msg, "%s: upnp:rootdevice\r\n", NTString);
188                 wpabuf_printf(msg, "USN: uuid:%s::upnp:rootdevice\r\n",
189                               uuid_string);
190                 break;
191         case 1:
192                 wpabuf_printf(msg, "%s: uuid:%s\r\n", NTString, uuid_string);
193                 wpabuf_printf(msg, "USN: uuid:%s\r\n", uuid_string);
194                 break;
195         case 2:
196                 wpabuf_printf(msg, "%s: urn:schemas-wifialliance-org:device:"
197                               "WFADevice:1\r\n", NTString);
198                 wpabuf_printf(msg, "USN: uuid:%s::urn:schemas-wifialliance-"
199                               "org:device:WFADevice:1\r\n", uuid_string);
200                 break;
201         case 3:
202                 wpabuf_printf(msg, "%s: urn:schemas-wifialliance-org:service:"
203                               "WFAWLANConfig:1\r\n", NTString);
204                 wpabuf_printf(msg, "USN: uuid:%s::urn:schemas-wifialliance-"
205                               "org:service:WFAWLANConfig:1\r\n", uuid_string);
206                 break;
207         }
208         wpabuf_put_str(msg, "\r\n");
209
210         if (a->state + 1 >= 4 * UPNP_ADVERTISE_REPEAT)
211                 *islast = 1;
212
213         return msg;
214
215 fail:
216         wpabuf_free(msg);
217         return NULL;
218 }
219
220
221 static void advertisement_state_machine_handler(void *eloop_data,
222                                                 void *user_ctx);
223
224
225 /**
226  * advertisement_state_machine_stop - Stop SSDP advertisements
227  * @sm: WPS UPnP state machine from upnp_wps_device_init()
228  * @send_byebye: Send byebye advertisement messages immediately
229  */
230 void advertisement_state_machine_stop(struct upnp_wps_device_sm *sm,
231                                       int send_byebye)
232 {
233         struct advertisement_state_machine *a = &sm->advertisement;
234         int islast = 0;
235         struct wpabuf *msg;
236         struct sockaddr_in dest;
237
238         eloop_cancel_timeout(advertisement_state_machine_handler, NULL, sm);
239         if (!send_byebye || sm->multicast_sd < 0)
240                 return;
241
242         a->type = ADVERTISE_DOWN;
243         a->state = 0;
244
245         os_memset(&dest, 0, sizeof(dest));
246         dest.sin_family = AF_INET;
247         dest.sin_addr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS);
248         dest.sin_port = htons(UPNP_MULTICAST_PORT);
249
250         while (!islast) {
251                 msg = next_advertisement(sm, a, &islast);
252                 if (msg == NULL)
253                         break;
254                 if (sendto(sm->multicast_sd, wpabuf_head(msg), wpabuf_len(msg),
255                            0, (struct sockaddr *) &dest, sizeof(dest)) < 0) {
256                         wpa_printf(MSG_INFO, "WPS UPnP: Advertisement sendto "
257                                    "failed: %d (%s)", errno, strerror(errno));
258                 }
259                 wpabuf_free(msg);
260                 a->state++;
261         }
262 }
263
264
265 static void advertisement_state_machine_handler(void *eloop_data,
266                                                 void *user_ctx)
267 {
268         struct upnp_wps_device_sm *sm = user_ctx;
269         struct advertisement_state_machine *a = &sm->advertisement;
270         struct wpabuf *msg;
271         int next_timeout_msec = 100;
272         int next_timeout_sec = 0;
273         struct sockaddr_in dest;
274         int islast = 0;
275
276         /*
277          * Each is sent twice (in case lost) w/ 100 msec delay between;
278          * spec says no more than 3 times.
279          * One pair for rootdevice, one pair for uuid, and a pair each for
280          * each of the two urns.
281          * The entire sequence must be repeated before cache control timeout
282          * (which  is min  1800 seconds),
283          * recommend random portion of half of the advertised cache control age
284          * to ensure against loss... perhaps 1800/4 + rand*1800/4 ?
285          * Delay random interval < 100 msec prior to initial sending.
286          * TTL of 4
287          */
288
289         wpa_printf(MSG_MSGDUMP, "WPS UPnP: Advertisement state=%d", a->state);
290         msg = next_advertisement(sm, a, &islast);
291         if (msg == NULL)
292                 return;
293
294         os_memset(&dest, 0, sizeof(dest));
295         dest.sin_family = AF_INET;
296         dest.sin_addr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS);
297         dest.sin_port = htons(UPNP_MULTICAST_PORT);
298
299         if (sendto(sm->multicast_sd, wpabuf_head(msg), wpabuf_len(msg), 0,
300                    (struct sockaddr *) &dest, sizeof(dest)) == -1) {
301                 wpa_printf(MSG_ERROR, "WPS UPnP: Advertisement sendto failed:"
302                            "%d (%s)", errno, strerror(errno));
303                 next_timeout_msec = 0;
304                 next_timeout_sec = 10; /* ... later */
305         } else if (islast) {
306                 a->state = 0; /* wrap around */
307                 if (a->type == ADVERTISE_DOWN) {
308                         wpa_printf(MSG_DEBUG, "WPS UPnP: ADVERTISE_DOWN->UP");
309                         a->type = ADVERTISE_UP;
310                         /* do it all over again right away */
311                 } else {
312                         u16 r;
313                         /*
314                          * Start over again after a long timeout
315                          * (see notes above)
316                          */
317                         next_timeout_msec = 0;
318                         os_get_random((void *) &r, sizeof(r));
319                         next_timeout_sec = UPNP_CACHE_SEC / 4 +
320                                 (((UPNP_CACHE_SEC / 4) * r) >> 16);
321                         sm->advertise_count++;
322                         wpa_printf(MSG_DEBUG, "WPS UPnP: ADVERTISE_UP (#%u); "
323                                    "next in %d sec",
324                                    sm->advertise_count, next_timeout_sec);
325                 }
326         } else {
327                 a->state++;
328         }
329
330         wpabuf_free(msg);
331
332         eloop_register_timeout(next_timeout_sec, next_timeout_msec,
333                                advertisement_state_machine_handler, NULL, sm);
334 }
335
336
337 /**
338  * advertisement_state_machine_start - Start SSDP advertisements
339  * @sm: WPS UPnP state machine from upnp_wps_device_init()
340  * Returns: 0 on success, -1 on failure
341  */
342 int advertisement_state_machine_start(struct upnp_wps_device_sm *sm)
343 {
344         struct advertisement_state_machine *a = &sm->advertisement;
345         int next_timeout_msec;
346
347         advertisement_state_machine_stop(sm, 0);
348
349         /*
350          * Start out advertising down, this automatically switches
351          * to advertising up which signals our restart.
352          */
353         a->type = ADVERTISE_DOWN;
354         a->state = 0;
355         /* (other fields not used here) */
356
357         /* First timeout should be random interval < 100 msec */
358         next_timeout_msec = (100 * (os_random() & 0xFF)) >> 8;
359         return eloop_register_timeout(0, next_timeout_msec,
360                                       advertisement_state_machine_handler,
361                                       NULL, sm);
362 }
363
364
365 /***************************************************************************
366  * M-SEARCH replies
367  * These are very similar to the multicast advertisements, with some
368  * small changes in data content; and they are sent (UDP) to a specific
369  * unicast address instead of multicast.
370  * They are sent in response to a UDP M-SEARCH packet.
371  **************************************************************************/
372
373 /**
374  * msearchreply_state_machine_stop - Stop M-SEARCH reply state machine
375  * @a: Selected advertisement/reply state
376  */
377 void msearchreply_state_machine_stop(struct advertisement_state_machine *a)
378 {
379         wpa_printf(MSG_DEBUG, "WPS UPnP: M-SEARCH stop");
380         dl_list_del(&a->list);
381         os_free(a);
382 }
383
384
385 static void msearchreply_state_machine_handler(void *eloop_data,
386                                                void *user_ctx)
387 {
388         struct advertisement_state_machine *a = user_ctx;
389         struct upnp_wps_device_sm *sm = eloop_data;
390         struct wpabuf *msg;
391         int next_timeout_msec = 100;
392         int next_timeout_sec = 0;
393         int islast = 0;
394
395         /*
396          * Each response is sent twice (in case lost) w/ 100 msec delay
397          * between; spec says no more than 3 times.
398          * One pair for rootdevice, one pair for uuid, and a pair each for
399          * each of the two urns.
400          */
401
402         /* TODO: should only send the requested response types */
403
404         wpa_printf(MSG_MSGDUMP, "WPS UPnP: M-SEARCH reply state=%d (%s:%d)",
405                    a->state, inet_ntoa(a->client.sin_addr),
406                    ntohs(a->client.sin_port));
407         msg = next_advertisement(sm, a, &islast);
408         if (msg == NULL)
409                 return;
410
411         /*
412          * Send it on the multicast socket to avoid having to set up another
413          * socket.
414          */
415         if (sendto(sm->multicast_sd, wpabuf_head(msg), wpabuf_len(msg), 0,
416                    (struct sockaddr *) &a->client, sizeof(a->client)) < 0) {
417                 wpa_printf(MSG_DEBUG, "WPS UPnP: M-SEARCH reply sendto "
418                            "errno %d (%s) for %s:%d",
419                            errno, strerror(errno),
420                            inet_ntoa(a->client.sin_addr),
421                            ntohs(a->client.sin_port));
422                 /* Ignore error and hope for the best */
423         }
424         wpabuf_free(msg);
425         if (islast) {
426                 wpa_printf(MSG_DEBUG, "WPS UPnP: M-SEARCH reply done");
427                 msearchreply_state_machine_stop(a);
428                 return;
429         }
430         a->state++;
431
432         wpa_printf(MSG_MSGDUMP, "WPS UPnP: M-SEARCH reply in %d.%03d sec",
433                    next_timeout_sec, next_timeout_msec);
434         eloop_register_timeout(next_timeout_sec, next_timeout_msec,
435                                msearchreply_state_machine_handler, sm, a);
436 }
437
438
439 /**
440  * msearchreply_state_machine_start - Reply to M-SEARCH discovery request
441  * @sm: WPS UPnP state machine from upnp_wps_device_init()
442  * @client: Client address
443  * @mx: Maximum delay in seconds
444  *
445  * Use TTL of 4 (this was done when socket set up).
446  * A response should be given in randomized portion of min(MX,120) seconds
447  *
448  * UPnP-arch-DeviceArchitecture, 1.2.3:
449  * To be found, a device must send a UDP response to the source IP address and
450  * port that sent the request to the multicast channel. Devices respond if the
451  * ST header of the M-SEARCH request is "ssdp:all", "upnp:rootdevice", "uuid:"
452  * followed by a UUID that exactly matches one advertised by the device.
453  */
454 static void msearchreply_state_machine_start(struct upnp_wps_device_sm *sm,
455                                              struct sockaddr_in *client,
456                                              int mx)
457 {
458         struct advertisement_state_machine *a;
459         int next_timeout_sec;
460         int next_timeout_msec;
461         int replies;
462
463         replies = dl_list_len(&sm->msearch_replies);
464         wpa_printf(MSG_DEBUG, "WPS UPnP: M-SEARCH reply start (%d "
465                    "outstanding)", replies);
466         if (replies >= MAX_MSEARCH) {
467                 wpa_printf(MSG_INFO, "WPS UPnP: Too many outstanding "
468                            "M-SEARCH replies");
469                 return;
470         }
471
472         a = os_zalloc(sizeof(*a));
473         if (a == NULL)
474                 return;
475         a->type = MSEARCH_REPLY;
476         a->state = 0;
477         os_memcpy(&a->client, client, sizeof(*client));
478         /* Wait time depending on MX value */
479         next_timeout_msec = (1000 * mx * (os_random() & 0xFF)) >> 8;
480         next_timeout_sec = next_timeout_msec / 1000;
481         next_timeout_msec = next_timeout_msec % 1000;
482         if (eloop_register_timeout(next_timeout_sec, next_timeout_msec,
483                                    msearchreply_state_machine_handler, sm,
484                                    a)) {
485                 /* No way to recover (from malloc failure) */
486                 goto fail;
487         }
488         /* Remember for future cleanup */
489         dl_list_add(&sm->msearch_replies, &a->list);
490         return;
491
492 fail:
493         wpa_printf(MSG_INFO, "WPS UPnP: M-SEARCH reply failure!");
494         eloop_cancel_timeout(msearchreply_state_machine_handler, sm, a);
495         os_free(a);
496 }
497
498
499 /**
500  * ssdp_parse_msearch - Process a received M-SEARCH
501  * @sm: WPS UPnP state machine from upnp_wps_device_init()
502  * @client: Client address
503  * @data: NULL terminated M-SEARCH message
504  *
505  * Given that we have received a header w/ M-SEARCH, act upon it
506  *
507  * Format of M-SEARCH (case insensitive!):
508  *
509  * First line must be:
510  *      M-SEARCH * HTTP/1.1
511  * Other lines in arbitrary order:
512  *      HOST:239.255.255.250:1900
513  *      ST:<varies -- must match>
514  *      MAN:"ssdp:discover"
515  *      MX:<varies>
516  *
517  * It should be noted that when Microsoft Vista is still learning its IP
518  * address, it sends out host lines like: HOST:[FF02::C]:1900
519  */
520 static void ssdp_parse_msearch(struct upnp_wps_device_sm *sm,
521                                struct sockaddr_in *client, const char *data)
522 {
523 #ifndef CONFIG_NO_STDOUT_DEBUG
524         const char *start = data;
525 #endif /* CONFIG_NO_STDOUT_DEBUG */
526         int got_host = 0;
527         int got_st = 0, st_match = 0;
528         int got_man = 0;
529         int got_mx = 0;
530         int mx = 0;
531
532         /*
533          * Skip first line M-SEARCH * HTTP/1.1
534          * (perhaps we should check remainder of the line for syntax)
535          */
536         data += line_length(data);
537
538         /* Parse remaining lines */
539         for (; *data != '\0'; data += line_length(data)) {
540                 if (token_eq(data, "host")) {
541                         /* The host line indicates who the packet
542                          * is addressed to... but do we really care?
543                          * Note that Microsoft sometimes does funny
544                          * stuff with the HOST: line.
545                          */
546 #if 0   /* could be */
547                         data += token_length(data);
548                         data += word_separation_length(data);
549                         if (*data != ':')
550                                 goto bad;
551                         data++;
552                         data += word_separation_length(data);
553                         /* UPNP_MULTICAST_ADDRESS */
554                         if (!str_starts(data, "239.255.255.250"))
555                                 goto bad;
556                         data += os_strlen("239.255.255.250");
557                         if (*data == ':') {
558                                 if (!str_starts(data, ":1900"))
559                                         goto bad;
560                         }
561 #endif  /* could be */
562                         got_host = 1;
563                         continue;
564                 } else if (token_eq(data, "st")) {
565                         /* There are a number of forms; we look
566                          * for one that matches our case.
567                          */
568                         got_st = 1;
569                         data += token_length(data);
570                         data += word_separation_length(data);
571                         if (*data != ':')
572                                 continue;
573                         data++;
574                         data += word_separation_length(data);
575                         if (str_starts(data, "ssdp:all")) {
576                                 st_match = 1;
577                                 continue;
578                         }
579                         if (str_starts(data, "upnp:rootdevice")) {
580                                 st_match = 1;
581                                 continue;
582                         }
583                         if (str_starts(data, "uuid:")) {
584                                 char uuid_string[80];
585                                 struct upnp_wps_device_interface *iface;
586                                 iface = dl_list_first(
587                                         &sm->interfaces,
588                                         struct upnp_wps_device_interface,
589                                         list);
590                                 data += os_strlen("uuid:");
591                                 uuid_bin2str(iface->wps->uuid, uuid_string,
592                                              sizeof(uuid_string));
593                                 if (str_starts(data, uuid_string))
594                                         st_match = 1;
595                                 continue;
596                         }
597 #if 0
598                         /* FIX: should we really reply to IGD string? */
599                         if (str_starts(data, "urn:schemas-upnp-org:device:"
600                                        "InternetGatewayDevice:1")) {
601                                 st_match = 1;
602                                 continue;
603                         }
604 #endif
605                         if (str_starts(data, "urn:schemas-wifialliance-org:"
606                                        "service:WFAWLANConfig:1")) {
607                                 st_match = 1;
608                                 continue;
609                         }
610                         if (str_starts(data, "urn:schemas-wifialliance-org:"
611                                        "device:WFADevice:1")) {
612                                 st_match = 1;
613                                 continue;
614                         }
615                         continue;
616                 } else if (token_eq(data, "man")) {
617                         data += token_length(data);
618                         data += word_separation_length(data);
619                         if (*data != ':')
620                                 continue;
621                         data++;
622                         data += word_separation_length(data);
623                         if (!str_starts(data, "\"ssdp:discover\"")) {
624                                 wpa_printf(MSG_DEBUG, "WPS UPnP: Unexpected "
625                                            "M-SEARCH man-field");
626                                 goto bad;
627                         }
628                         got_man = 1;
629                         continue;
630                 } else if (token_eq(data, "mx")) {
631                         data += token_length(data);
632                         data += word_separation_length(data);
633                         if (*data != ':')
634                                 continue;
635                         data++;
636                         data += word_separation_length(data);
637                         mx = atol(data);
638                         got_mx = 1;
639                         continue;
640                 }
641                 /* ignore anything else */
642         }
643         if (!got_host || !got_st || !got_man || !got_mx || mx < 0) {
644                 wpa_printf(MSG_DEBUG, "WPS UPnP: Invalid M-SEARCH: %d %d %d "
645                            "%d mx=%d", got_host, got_st, got_man, got_mx, mx);
646                 goto bad;
647         }
648         if (!st_match) {
649                 wpa_printf(MSG_DEBUG, "WPS UPnP: Ignored M-SEARCH (no ST "
650                            "match)");
651                 return;
652         }
653         if (mx > 120)
654                 mx = 120; /* UPnP-arch-DeviceArchitecture, 1.2.3 */
655         msearchreply_state_machine_start(sm, client, mx);
656         return;
657
658 bad:
659         wpa_printf(MSG_INFO, "WPS UPnP: Failed to parse M-SEARCH");
660         wpa_printf(MSG_MSGDUMP, "WPS UPnP: M-SEARCH data:\n%s", start);
661 }
662
663
664 /* Listening for (UDP) discovery (M-SEARCH) packets */
665
666 /**
667  * ssdp_listener_stop - Stop SSDP listered
668  * @sm: WPS UPnP state machine from upnp_wps_device_init()
669  *
670  * This function stops the SSDP listener that was started by calling
671  * ssdp_listener_start().
672  */
673 void ssdp_listener_stop(struct upnp_wps_device_sm *sm)
674 {
675         if (sm->ssdp_sd_registered) {
676                 eloop_unregister_sock(sm->ssdp_sd, EVENT_TYPE_READ);
677                 sm->ssdp_sd_registered = 0;
678         }
679
680         if (sm->ssdp_sd != -1) {
681                 close(sm->ssdp_sd);
682                 sm->ssdp_sd = -1;
683         }
684
685         eloop_cancel_timeout(msearchreply_state_machine_handler, sm,
686                              ELOOP_ALL_CTX);
687 }
688
689
690 static void ssdp_listener_handler(int sd, void *eloop_ctx, void *sock_ctx)
691 {
692         struct upnp_wps_device_sm *sm = sock_ctx;
693         struct sockaddr_in addr; /* client address */
694         socklen_t addr_len;
695         int nread;
696         char buf[MULTICAST_MAX_READ], *pos;
697
698         addr_len = sizeof(addr);
699         nread = recvfrom(sm->ssdp_sd, buf, sizeof(buf) - 1, 0,
700                          (struct sockaddr *) &addr, &addr_len);
701         if (nread <= 0)
702                 return;
703         buf[nread] = '\0'; /* need null termination for algorithm */
704
705         if (str_starts(buf, "NOTIFY ")) {
706                 /*
707                  * Silently ignore NOTIFYs to avoid filling debug log with
708                  * unwanted messages.
709                  */
710                 return;
711         }
712
713         pos = os_strchr(buf, '\n');
714         if (pos)
715                 *pos = '\0';
716         wpa_printf(MSG_MSGDUMP, "WPS UPnP: Received SSDP packet from %s:%d: "
717                    "%s", inet_ntoa(addr.sin_addr), ntohs(addr.sin_port), buf);
718         if (pos)
719                 *pos = '\n';
720
721         /* Parse first line */
722         if (os_strncasecmp(buf, "M-SEARCH", os_strlen("M-SEARCH")) == 0 &&
723             !isgraph(buf[strlen("M-SEARCH")])) {
724                 ssdp_parse_msearch(sm, &addr, buf);
725                 return;
726         }
727
728         /* Ignore anything else */
729 }
730
731
732 int ssdp_listener_open(void)
733 {
734         struct sockaddr_in addr;
735         struct ip_mreq mcast_addr;
736         int on = 1;
737         /* per UPnP spec, keep IP packet time to live (TTL) small */
738         unsigned char ttl = 4;
739         int sd;
740
741         sd = socket(AF_INET, SOCK_DGRAM, 0);
742         if (sd < 0)
743                 goto fail;
744         if (fcntl(sd, F_SETFL, O_NONBLOCK) != 0)
745                 goto fail;
746         if (setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)))
747                 goto fail;
748         os_memset(&addr, 0, sizeof(addr));
749         addr.sin_family = AF_INET;
750         addr.sin_addr.s_addr = htonl(INADDR_ANY);
751         addr.sin_port = htons(UPNP_MULTICAST_PORT);
752         if (bind(sd, (struct sockaddr *) &addr, sizeof(addr)))
753                 goto fail;
754         os_memset(&mcast_addr, 0, sizeof(mcast_addr));
755         mcast_addr.imr_interface.s_addr = htonl(INADDR_ANY);
756         mcast_addr.imr_multiaddr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS);
757         if (setsockopt(sd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
758                        (char *) &mcast_addr, sizeof(mcast_addr)))
759                 goto fail;
760         if (setsockopt(sd, IPPROTO_IP, IP_MULTICAST_TTL,
761                        &ttl, sizeof(ttl)))
762                 goto fail;
763
764         return sd;
765
766 fail:
767         if (sd >= 0)
768                 close(sd);
769         return -1;
770 }
771
772
773 /**
774  * ssdp_listener_start - Set up for receiving discovery (UDP) packets
775  * @sm: WPS UPnP state machine from upnp_wps_device_init()
776  * Returns: 0 on success, -1 on failure
777  *
778  * The SSDP listener is stopped by calling ssdp_listener_stop().
779  */
780 int ssdp_listener_start(struct upnp_wps_device_sm *sm)
781 {
782         sm->ssdp_sd = ssdp_listener_open();
783
784         if (eloop_register_sock(sm->ssdp_sd, EVENT_TYPE_READ,
785                                 ssdp_listener_handler, NULL, sm))
786                 goto fail;
787         sm->ssdp_sd_registered = 1;
788         return 0;
789
790 fail:
791         /* Error */
792         wpa_printf(MSG_ERROR, "WPS UPnP: ssdp_listener_start failed");
793         ssdp_listener_stop(sm);
794         return -1;
795 }
796
797
798 /**
799  * add_ssdp_network - Add routing entry for SSDP
800  * @net_if: Selected network interface name
801  * Returns: 0 on success, -1 on failure
802  *
803  * This function assures that the multicast address will be properly
804  * handled by Linux networking code (by a modification to routing tables).
805  * This must be done per network interface. It really only needs to be done
806  * once after booting up, but it does not hurt to call this more frequently
807  * "to be safe".
808  */
809 int add_ssdp_network(const char *net_if)
810 {
811 #ifdef __linux__
812         int ret = -1;
813         int sock = -1;
814         struct rtentry rt;
815         struct sockaddr_in *sin;
816
817         if (!net_if)
818                 goto fail;
819
820         os_memset(&rt, 0, sizeof(rt));
821         sock = socket(AF_INET, SOCK_DGRAM, 0);
822         if (sock < 0)
823                 goto fail;
824
825         rt.rt_dev = (char *) net_if;
826         sin = aliasing_hide_typecast(&rt.rt_dst, struct sockaddr_in);
827         sin->sin_family = AF_INET;
828         sin->sin_port = 0;
829         sin->sin_addr.s_addr = inet_addr(SSDP_TARGET);
830         sin = aliasing_hide_typecast(&rt.rt_genmask, struct sockaddr_in);
831         sin->sin_family = AF_INET;
832         sin->sin_port = 0;
833         sin->sin_addr.s_addr = inet_addr(SSDP_NETMASK);
834         rt.rt_flags = RTF_UP;
835         if (ioctl(sock, SIOCADDRT, &rt) < 0) {
836                 if (errno == EPERM) {
837                         wpa_printf(MSG_DEBUG, "add_ssdp_network: No "
838                                    "permissions to add routing table entry");
839                         /* Continue to allow testing as non-root */
840                 } else if (errno != EEXIST) {
841                         wpa_printf(MSG_INFO, "add_ssdp_network() ioctl errno "
842                                    "%d (%s)", errno, strerror(errno));
843                         goto fail;
844                 }
845         }
846
847         ret = 0;
848
849 fail:
850         if (sock >= 0)
851                 close(sock);
852
853         return ret;
854 #else /* __linux__ */
855         return 0;
856 #endif /* __linux__ */
857 }
858
859
860 int ssdp_open_multicast_sock(u32 ip_addr, const char *forced_ifname)
861 {
862         int sd;
863          /* per UPnP-arch-DeviceArchitecture, 1. Discovery, keep IP packet
864           * time to live (TTL) small */
865         unsigned char ttl = 4;
866
867         sd = socket(AF_INET, SOCK_DGRAM, 0);
868         if (sd < 0)
869                 return -1;
870
871         if (forced_ifname) {
872 #ifdef __linux__
873                 struct ifreq req;
874                 os_memset(&req, 0, sizeof(req));
875                 os_strlcpy(req.ifr_name, forced_ifname, sizeof(req.ifr_name));
876                 if (setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, &req,
877                                sizeof(req)) < 0) {
878                         wpa_printf(MSG_INFO, "WPS UPnP: Failed to bind "
879                                    "multicast socket to ifname %s: %s",
880                                    forced_ifname, strerror(errno));
881                         close(sd);
882                         return -1;
883                 }
884 #endif /* __linux__ */
885         }
886
887 #if 0   /* maybe ok if we sometimes block on writes */
888         if (fcntl(sd, F_SETFL, O_NONBLOCK) != 0) {
889                 close(sd);
890                 return -1;
891         }
892 #endif
893
894         if (setsockopt(sd, IPPROTO_IP, IP_MULTICAST_IF,
895                        &ip_addr, sizeof(ip_addr))) {
896                 wpa_printf(MSG_DEBUG, "WPS: setsockopt(IP_MULTICAST_IF) %x: "
897                            "%d (%s)", ip_addr, errno, strerror(errno));
898                 close(sd);
899                 return -1;
900         }
901         if (setsockopt(sd, IPPROTO_IP, IP_MULTICAST_TTL,
902                        &ttl, sizeof(ttl))) {
903                 wpa_printf(MSG_DEBUG, "WPS: setsockopt(IP_MULTICAST_TTL): "
904                            "%d (%s)", errno, strerror(errno));
905                 close(sd);
906                 return -1;
907         }
908
909 #if 0   /* not needed, because we don't receive using multicast_sd */
910         {
911                 struct ip_mreq mreq;
912                 mreq.imr_multiaddr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS);
913                 mreq.imr_interface.s_addr = ip_addr;
914                 wpa_printf(MSG_DEBUG, "WPS UPnP: Multicast addr 0x%x if addr "
915                            "0x%x",
916                            mreq.imr_multiaddr.s_addr,
917                            mreq.imr_interface.s_addr);
918                 if (setsockopt(sd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq,
919                                 sizeof(mreq))) {
920                         wpa_printf(MSG_ERROR,
921                                    "WPS UPnP: setsockopt "
922                                    "IP_ADD_MEMBERSHIP errno %d (%s)",
923                                    errno, strerror(errno));
924                         close(sd);
925                         return -1;
926                 }
927         }
928 #endif  /* not needed */
929
930         /*
931          * TODO: What about IP_MULTICAST_LOOP? It seems to be on by default?
932          * which aids debugging I suppose but isn't really necessary?
933          */
934
935         return sd;
936 }
937
938
939 /**
940  * ssdp_open_multicast - Open socket for sending multicast SSDP messages
941  * @sm: WPS UPnP state machine from upnp_wps_device_init()
942  * Returns: 0 on success, -1 on failure
943  */
944 int ssdp_open_multicast(struct upnp_wps_device_sm *sm)
945 {
946         sm->multicast_sd = ssdp_open_multicast_sock(sm->ip_addr, NULL);
947         if (sm->multicast_sd < 0)
948                 return -1;
949         return 0;
950 }