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