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 /*************************************************************************** 104 * Advertisements. 105 * These are multicast to the world to tell them we are here. 106 * The individual packets are spread out in time to limit loss, 107 * and then after a much longer period of time the whole sequence 108 * is repeated again (for NOTIFYs only). 109 **************************************************************************/ 110 111 /** 112 * next_advertisement - Build next message and advance the state machine 113 * @a: Advertisement state 114 * @islast: Buffer for indicating whether this is the last message (= 1) 115 * Returns: The new message (caller is responsible for freeing this) 116 * 117 * Note: next_advertisement is shared code with msearchreply_* functions 118 */ 119 static struct wpabuf * 120 next_advertisement(struct upnp_wps_device_sm *sm, 121 struct advertisement_state_machine *a, int *islast) 122 { 123 struct wpabuf *msg; 124 char *NTString = ""; 125 char uuid_string[80]; 126 struct upnp_wps_device_interface *iface; 127 128 *islast = 0; 129 iface = dl_list_first(&sm->interfaces, 130 struct upnp_wps_device_interface, list); 131 if (!iface) 132 return NULL; 133 uuid_bin2str(iface->wps->uuid, uuid_string, sizeof(uuid_string)); 134 msg = wpabuf_alloc(800); /* more than big enough */ 135 if (msg == NULL) 136 return NULL; 137 switch (a->type) { 138 case ADVERTISE_UP: 139 case ADVERTISE_DOWN: 140 NTString = "NT"; 141 wpabuf_put_str(msg, "NOTIFY * HTTP/1.1\r\n"); 142 wpabuf_printf(msg, "HOST: %s:%d\r\n", 143 UPNP_MULTICAST_ADDRESS, UPNP_MULTICAST_PORT); 144 wpabuf_printf(msg, "CACHE-CONTROL: max-age=%d\r\n", 145 UPNP_CACHE_SEC); 146 wpabuf_printf(msg, "NTS: %s\r\n", 147 (a->type == ADVERTISE_UP ? 148 "ssdp:alive" : "ssdp:byebye")); 149 break; 150 case MSEARCH_REPLY: 151 NTString = "ST"; 152 wpabuf_put_str(msg, "HTTP/1.1 200 OK\r\n"); 153 wpabuf_printf(msg, "CACHE-CONTROL: max-age=%d\r\n", 154 UPNP_CACHE_SEC); 155 156 wpabuf_put_str(msg, "DATE: "); 157 format_date(msg); 158 wpabuf_put_str(msg, "\r\n"); 159 160 wpabuf_put_str(msg, "EXT:\r\n"); 161 break; 162 } 163 164 if (a->type != ADVERTISE_DOWN) { 165 /* Where others may get our XML files from */ 166 wpabuf_printf(msg, "LOCATION: http://%s:%d/%s\r\n", 167 sm->ip_addr_text, sm->web_port, 168 UPNP_WPS_DEVICE_XML_FILE); 169 } 170 171 /* The SERVER line has three comma-separated fields: 172 * operating system / version 173 * upnp version 174 * software package / version 175 * However, only the UPnP version is really required, the 176 * others can be place holders... for security reasons 177 * it is better to NOT provide extra information. 178 */ 179 wpabuf_put_str(msg, "SERVER: Unspecified, UPnP/1.0, Unspecified\r\n"); 180 181 switch (a->state / UPNP_ADVERTISE_REPEAT) { 182 case 0: 183 wpabuf_printf(msg, "%s: upnp:rootdevice\r\n", NTString); 184 wpabuf_printf(msg, "USN: uuid:%s::upnp:rootdevice\r\n", 185 uuid_string); 186 break; 187 case 1: 188 wpabuf_printf(msg, "%s: uuid:%s\r\n", NTString, uuid_string); 189 wpabuf_printf(msg, "USN: uuid:%s\r\n", uuid_string); 190 break; 191 case 2: 192 wpabuf_printf(msg, "%s: urn:schemas-wifialliance-org:device:" 193 "WFADevice:1\r\n", NTString); 194 wpabuf_printf(msg, "USN: uuid:%s::urn:schemas-wifialliance-" 195 "org:device:WFADevice:1\r\n", uuid_string); 196 break; 197 case 3: 198 wpabuf_printf(msg, "%s: urn:schemas-wifialliance-org:service:" 199 "WFAWLANConfig:1\r\n", NTString); 200 wpabuf_printf(msg, "USN: uuid:%s::urn:schemas-wifialliance-" 201 "org:service:WFAWLANConfig:1\r\n", uuid_string); 202 break; 203 } 204 wpabuf_put_str(msg, "\r\n"); 205 206 if (a->state + 1 >= 4 * UPNP_ADVERTISE_REPEAT) 207 *islast = 1; 208 209 return msg; 210 } 211 212 213 static void advertisement_state_machine_handler(void *eloop_data, 214 void *user_ctx); 215 216 217 /** 218 * advertisement_state_machine_stop - Stop SSDP advertisements 219 * @sm: WPS UPnP state machine from upnp_wps_device_init() 220 * @send_byebye: Send byebye advertisement messages immediately 221 */ 222 void advertisement_state_machine_stop(struct upnp_wps_device_sm *sm, 223 int send_byebye) 224 { 225 struct advertisement_state_machine *a = &sm->advertisement; 226 int islast = 0; 227 struct wpabuf *msg; 228 struct sockaddr_in dest; 229 230 eloop_cancel_timeout(advertisement_state_machine_handler, NULL, sm); 231 if (!send_byebye || sm->multicast_sd < 0) 232 return; 233 234 a->type = ADVERTISE_DOWN; 235 a->state = 0; 236 237 os_memset(&dest, 0, sizeof(dest)); 238 dest.sin_family = AF_INET; 239 dest.sin_addr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS); 240 dest.sin_port = htons(UPNP_MULTICAST_PORT); 241 242 while (!islast) { 243 msg = next_advertisement(sm, a, &islast); 244 if (msg == NULL) 245 break; 246 if (sendto(sm->multicast_sd, wpabuf_head(msg), wpabuf_len(msg), 247 0, (struct sockaddr *) &dest, sizeof(dest)) < 0) { 248 wpa_printf(MSG_INFO, "WPS UPnP: Advertisement sendto " 249 "failed: %d (%s)", errno, strerror(errno)); 250 } 251 wpabuf_free(msg); 252 a->state++; 253 } 254 } 255 256 257 static void advertisement_state_machine_handler(void *eloop_data, 258 void *user_ctx) 259 { 260 struct upnp_wps_device_sm *sm = user_ctx; 261 struct advertisement_state_machine *a = &sm->advertisement; 262 struct wpabuf *msg; 263 int next_timeout_msec = 100; 264 int next_timeout_sec = 0; 265 struct sockaddr_in dest; 266 int islast = 0; 267 268 /* 269 * Each is sent twice (in case lost) w/ 100 msec delay between; 270 * spec says no more than 3 times. 271 * One pair for rootdevice, one pair for uuid, and a pair each for 272 * each of the two urns. 273 * The entire sequence must be repeated before cache control timeout 274 * (which is min 1800 seconds), 275 * recommend random portion of half of the advertised cache control age 276 * to ensure against loss... perhaps 1800/4 + rand*1800/4 ? 277 * Delay random interval < 100 msec prior to initial sending. 278 * TTL of 4 279 */ 280 281 wpa_printf(MSG_MSGDUMP, "WPS UPnP: Advertisement state=%d", a->state); 282 msg = next_advertisement(sm, a, &islast); 283 if (msg == NULL) 284 return; 285 286 os_memset(&dest, 0, sizeof(dest)); 287 dest.sin_family = AF_INET; 288 dest.sin_addr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS); 289 dest.sin_port = htons(UPNP_MULTICAST_PORT); 290 291 if (sendto(sm->multicast_sd, wpabuf_head(msg), wpabuf_len(msg), 0, 292 (struct sockaddr *) &dest, sizeof(dest)) == -1) { 293 wpa_printf(MSG_ERROR, "WPS UPnP: Advertisement sendto failed:" 294 "%d (%s)", errno, strerror(errno)); 295 next_timeout_msec = 0; 296 next_timeout_sec = 10; /* ... later */ 297 } else if (islast) { 298 a->state = 0; /* wrap around */ 299 if (a->type == ADVERTISE_DOWN) { 300 wpa_printf(MSG_DEBUG, "WPS UPnP: ADVERTISE_DOWN->UP"); 301 a->type = ADVERTISE_UP; 302 /* do it all over again right away */ 303 } else { 304 u16 r; 305 /* 306 * Start over again after a long timeout 307 * (see notes above) 308 */ 309 next_timeout_msec = 0; 310 if (os_get_random((void *) &r, sizeof(r)) < 0) 311 r = 32768; 312 next_timeout_sec = UPNP_CACHE_SEC / 4 + 313 (((UPNP_CACHE_SEC / 4) * r) >> 16); 314 sm->advertise_count++; 315 wpa_printf(MSG_DEBUG, "WPS UPnP: ADVERTISE_UP (#%u); " 316 "next in %d sec", 317 sm->advertise_count, next_timeout_sec); 318 } 319 } else { 320 a->state++; 321 } 322 323 wpabuf_free(msg); 324 325 eloop_register_timeout(next_timeout_sec, next_timeout_msec, 326 advertisement_state_machine_handler, NULL, sm); 327 } 328 329 330 /** 331 * advertisement_state_machine_start - Start SSDP advertisements 332 * @sm: WPS UPnP state machine from upnp_wps_device_init() 333 * Returns: 0 on success, -1 on failure 334 */ 335 int advertisement_state_machine_start(struct upnp_wps_device_sm *sm) 336 { 337 struct advertisement_state_machine *a = &sm->advertisement; 338 int next_timeout_msec; 339 340 advertisement_state_machine_stop(sm, 0); 341 342 /* 343 * Start out advertising down, this automatically switches 344 * to advertising up which signals our restart. 345 */ 346 a->type = ADVERTISE_DOWN; 347 a->state = 0; 348 /* (other fields not used here) */ 349 350 /* First timeout should be random interval < 100 msec */ 351 next_timeout_msec = (100 * (os_random() & 0xFF)) >> 8; 352 return eloop_register_timeout(0, next_timeout_msec, 353 advertisement_state_machine_handler, 354 NULL, sm); 355 } 356 357 358 /*************************************************************************** 359 * M-SEARCH replies 360 * These are very similar to the multicast advertisements, with some 361 * small changes in data content; and they are sent (UDP) to a specific 362 * unicast address instead of multicast. 363 * They are sent in response to a UDP M-SEARCH packet. 364 **************************************************************************/ 365 366 /** 367 * msearchreply_state_machine_stop - Stop M-SEARCH reply state machine 368 * @a: Selected advertisement/reply state 369 */ 370 void msearchreply_state_machine_stop(struct advertisement_state_machine *a) 371 { 372 wpa_printf(MSG_DEBUG, "WPS UPnP: M-SEARCH stop"); 373 dl_list_del(&a->list); 374 os_free(a); 375 } 376 377 378 static void msearchreply_state_machine_handler(void *eloop_data, 379 void *user_ctx) 380 { 381 struct advertisement_state_machine *a = user_ctx; 382 struct upnp_wps_device_sm *sm = eloop_data; 383 struct wpabuf *msg; 384 int next_timeout_msec = 100; 385 int next_timeout_sec = 0; 386 int islast = 0; 387 388 /* 389 * Each response is sent twice (in case lost) w/ 100 msec delay 390 * between; spec says no more than 3 times. 391 * One pair for rootdevice, one pair for uuid, and a pair each for 392 * each of the two urns. 393 */ 394 395 /* TODO: should only send the requested response types */ 396 397 wpa_printf(MSG_MSGDUMP, "WPS UPnP: M-SEARCH reply state=%d (%s:%d)", 398 a->state, inet_ntoa(a->client.sin_addr), 399 ntohs(a->client.sin_port)); 400 msg = next_advertisement(sm, a, &islast); 401 if (msg == NULL) 402 return; 403 404 /* 405 * Send it on the multicast socket to avoid having to set up another 406 * socket. 407 */ 408 if (sendto(sm->multicast_sd, wpabuf_head(msg), wpabuf_len(msg), 0, 409 (struct sockaddr *) &a->client, sizeof(a->client)) < 0) { 410 wpa_printf(MSG_DEBUG, "WPS UPnP: M-SEARCH reply sendto " 411 "errno %d (%s) for %s:%d", 412 errno, strerror(errno), 413 inet_ntoa(a->client.sin_addr), 414 ntohs(a->client.sin_port)); 415 /* Ignore error and hope for the best */ 416 } 417 wpabuf_free(msg); 418 if (islast) { 419 wpa_printf(MSG_DEBUG, "WPS UPnP: M-SEARCH reply done"); 420 msearchreply_state_machine_stop(a); 421 return; 422 } 423 a->state++; 424 425 wpa_printf(MSG_MSGDUMP, "WPS UPnP: M-SEARCH reply in %d.%03d sec", 426 next_timeout_sec, next_timeout_msec); 427 eloop_register_timeout(next_timeout_sec, next_timeout_msec, 428 msearchreply_state_machine_handler, sm, a); 429 } 430 431 432 /** 433 * msearchreply_state_machine_start - Reply to M-SEARCH discovery request 434 * @sm: WPS UPnP state machine from upnp_wps_device_init() 435 * @client: Client address 436 * @mx: Maximum delay in seconds 437 * 438 * Use TTL of 4 (this was done when socket set up). 439 * A response should be given in randomized portion of min(MX,120) seconds 440 * 441 * UPnP-arch-DeviceArchitecture, 1.2.3: 442 * To be found, a device must send a UDP response to the source IP address and 443 * port that sent the request to the multicast channel. Devices respond if the 444 * ST header of the M-SEARCH request is "ssdp:all", "upnp:rootdevice", "uuid:" 445 * followed by a UUID that exactly matches one advertised by the device. 446 */ 447 static void msearchreply_state_machine_start(struct upnp_wps_device_sm *sm, 448 struct sockaddr_in *client, 449 int mx) 450 { 451 struct advertisement_state_machine *a; 452 int next_timeout_sec; 453 int next_timeout_msec; 454 int replies; 455 456 replies = dl_list_len(&sm->msearch_replies); 457 wpa_printf(MSG_DEBUG, "WPS UPnP: M-SEARCH reply start (%d " 458 "outstanding)", replies); 459 if (replies >= MAX_MSEARCH) { 460 wpa_printf(MSG_INFO, "WPS UPnP: Too many outstanding " 461 "M-SEARCH replies"); 462 return; 463 } 464 465 a = os_zalloc(sizeof(*a)); 466 if (a == NULL) 467 return; 468 a->type = MSEARCH_REPLY; 469 a->state = 0; 470 os_memcpy(&a->client, client, sizeof(*client)); 471 /* Wait time depending on MX value */ 472 next_timeout_msec = (1000 * mx * (os_random() & 0xFF)) >> 8; 473 next_timeout_sec = next_timeout_msec / 1000; 474 next_timeout_msec = next_timeout_msec % 1000; 475 if (eloop_register_timeout(next_timeout_sec, next_timeout_msec, 476 msearchreply_state_machine_handler, sm, 477 a)) { 478 /* No way to recover (from malloc failure) */ 479 goto fail; 480 } 481 /* Remember for future cleanup */ 482 dl_list_add(&sm->msearch_replies, &a->list); 483 return; 484 485 fail: 486 wpa_printf(MSG_INFO, "WPS UPnP: M-SEARCH reply failure!"); 487 eloop_cancel_timeout(msearchreply_state_machine_handler, sm, a); 488 os_free(a); 489 } 490 491 492 /** 493 * ssdp_parse_msearch - Process a received M-SEARCH 494 * @sm: WPS UPnP state machine from upnp_wps_device_init() 495 * @client: Client address 496 * @data: NULL terminated M-SEARCH message 497 * 498 * Given that we have received a header w/ M-SEARCH, act upon it 499 * 500 * Format of M-SEARCH (case insensitive!): 501 * 502 * First line must be: 503 * M-SEARCH * HTTP/1.1 504 * Other lines in arbitrary order: 505 * HOST:239.255.255.250:1900 506 * ST:<varies -- must match> 507 * MAN:"ssdp:discover" 508 * MX:<varies> 509 * 510 * It should be noted that when Microsoft Vista is still learning its IP 511 * address, it sends out host lines like: HOST:[FF02::C]:1900 512 */ 513 static void ssdp_parse_msearch(struct upnp_wps_device_sm *sm, 514 struct sockaddr_in *client, const char *data) 515 { 516 #ifndef CONFIG_NO_STDOUT_DEBUG 517 const char *start = data; 518 #endif /* CONFIG_NO_STDOUT_DEBUG */ 519 int got_host = 0; 520 int got_st = 0, st_match = 0; 521 int got_man = 0; 522 int got_mx = 0; 523 int mx = 0; 524 525 /* 526 * Skip first line M-SEARCH * HTTP/1.1 527 * (perhaps we should check remainder of the line for syntax) 528 */ 529 data += line_length(data); 530 531 /* Parse remaining lines */ 532 for (; *data != '\0'; data += line_length(data)) { 533 if (token_eq(data, "host")) { 534 /* The host line indicates who the packet 535 * is addressed to... but do we really care? 536 * Note that Microsoft sometimes does funny 537 * stuff with the HOST: line. 538 */ 539 #if 0 /* could be */ 540 data += token_length(data); 541 data += word_separation_length(data); 542 if (*data != ':') 543 goto bad; 544 data++; 545 data += word_separation_length(data); 546 /* UPNP_MULTICAST_ADDRESS */ 547 if (!str_starts(data, "239.255.255.250")) 548 goto bad; 549 data += os_strlen("239.255.255.250"); 550 if (*data == ':') { 551 if (!str_starts(data, ":1900")) 552 goto bad; 553 } 554 #endif /* could be */ 555 got_host = 1; 556 continue; 557 } else if (token_eq(data, "st")) { 558 /* There are a number of forms; we look 559 * for one that matches our case. 560 */ 561 got_st = 1; 562 data += token_length(data); 563 data += word_separation_length(data); 564 if (*data != ':') 565 continue; 566 data++; 567 data += word_separation_length(data); 568 if (str_starts(data, "ssdp:all")) { 569 st_match = 1; 570 continue; 571 } 572 if (str_starts(data, "upnp:rootdevice")) { 573 st_match = 1; 574 continue; 575 } 576 if (str_starts(data, "uuid:")) { 577 char uuid_string[80]; 578 struct upnp_wps_device_interface *iface; 579 iface = dl_list_first( 580 &sm->interfaces, 581 struct upnp_wps_device_interface, 582 list); 583 if (!iface) 584 continue; 585 data += os_strlen("uuid:"); 586 uuid_bin2str(iface->wps->uuid, uuid_string, 587 sizeof(uuid_string)); 588 if (str_starts(data, uuid_string)) 589 st_match = 1; 590 continue; 591 } 592 #if 0 593 /* FIX: should we really reply to IGD string? */ 594 if (str_starts(data, "urn:schemas-upnp-org:device:" 595 "InternetGatewayDevice:1")) { 596 st_match = 1; 597 continue; 598 } 599 #endif 600 if (str_starts(data, "urn:schemas-wifialliance-org:" 601 "service:WFAWLANConfig:1")) { 602 st_match = 1; 603 continue; 604 } 605 if (str_starts(data, "urn:schemas-wifialliance-org:" 606 "device:WFADevice:1")) { 607 st_match = 1; 608 continue; 609 } 610 continue; 611 } else if (token_eq(data, "man")) { 612 data += token_length(data); 613 data += word_separation_length(data); 614 if (*data != ':') 615 continue; 616 data++; 617 data += word_separation_length(data); 618 if (!str_starts(data, "\"ssdp:discover\"")) { 619 wpa_printf(MSG_DEBUG, "WPS UPnP: Unexpected " 620 "M-SEARCH man-field"); 621 goto bad; 622 } 623 got_man = 1; 624 continue; 625 } else if (token_eq(data, "mx")) { 626 data += token_length(data); 627 data += word_separation_length(data); 628 if (*data != ':') 629 continue; 630 data++; 631 data += word_separation_length(data); 632 mx = atol(data); 633 got_mx = 1; 634 continue; 635 } 636 /* ignore anything else */ 637 } 638 if (!got_host || !got_st || !got_man || !got_mx || mx < 0) { 639 wpa_printf(MSG_DEBUG, "WPS UPnP: Invalid M-SEARCH: %d %d %d " 640 "%d mx=%d", got_host, got_st, got_man, got_mx, mx); 641 goto bad; 642 } 643 if (!st_match) { 644 wpa_printf(MSG_DEBUG, "WPS UPnP: Ignored M-SEARCH (no ST " 645 "match)"); 646 return; 647 } 648 if (mx > 120) 649 mx = 120; /* UPnP-arch-DeviceArchitecture, 1.2.3 */ 650 msearchreply_state_machine_start(sm, client, mx); 651 return; 652 653 bad: 654 wpa_printf(MSG_INFO, "WPS UPnP: Failed to parse M-SEARCH"); 655 wpa_printf(MSG_MSGDUMP, "WPS UPnP: M-SEARCH data:\n%s", start); 656 } 657 658 659 /* Listening for (UDP) discovery (M-SEARCH) packets */ 660 661 /** 662 * ssdp_listener_stop - Stop SSDP listered 663 * @sm: WPS UPnP state machine from upnp_wps_device_init() 664 * 665 * This function stops the SSDP listener that was started by calling 666 * ssdp_listener_start(). 667 */ 668 void ssdp_listener_stop(struct upnp_wps_device_sm *sm) 669 { 670 if (sm->ssdp_sd_registered) { 671 eloop_unregister_sock(sm->ssdp_sd, EVENT_TYPE_READ); 672 sm->ssdp_sd_registered = 0; 673 } 674 675 if (sm->ssdp_sd != -1) { 676 close(sm->ssdp_sd); 677 sm->ssdp_sd = -1; 678 } 679 680 eloop_cancel_timeout(msearchreply_state_machine_handler, sm, 681 ELOOP_ALL_CTX); 682 } 683 684 685 static void ssdp_listener_handler(int sd, void *eloop_ctx, void *sock_ctx) 686 { 687 struct upnp_wps_device_sm *sm = sock_ctx; 688 struct sockaddr_in addr; /* client address */ 689 socklen_t addr_len; 690 int nread; 691 char buf[MULTICAST_MAX_READ], *pos; 692 693 addr_len = sizeof(addr); 694 nread = recvfrom(sm->ssdp_sd, buf, sizeof(buf) - 1, 0, 695 (struct sockaddr *) &addr, &addr_len); 696 if (nread <= 0) 697 return; 698 buf[nread] = '\0'; /* need null termination for algorithm */ 699 700 if (str_starts(buf, "NOTIFY ")) { 701 /* 702 * Silently ignore NOTIFYs to avoid filling debug log with 703 * unwanted messages. 704 */ 705 return; 706 } 707 708 pos = os_strchr(buf, '\n'); 709 if (pos) 710 *pos = '\0'; 711 wpa_printf(MSG_MSGDUMP, "WPS UPnP: Received SSDP packet from %s:%d: " 712 "%s", inet_ntoa(addr.sin_addr), ntohs(addr.sin_port), buf); 713 if (pos) 714 *pos = '\n'; 715 716 /* Parse first line */ 717 if (os_strncasecmp(buf, "M-SEARCH", os_strlen("M-SEARCH")) == 0 && 718 !isgraph(buf[strlen("M-SEARCH")])) { 719 ssdp_parse_msearch(sm, &addr, buf); 720 return; 721 } 722 723 /* Ignore anything else */ 724 } 725 726 727 int ssdp_listener_open(void) 728 { 729 struct sockaddr_in addr; 730 struct ip_mreq mcast_addr; 731 int on = 1; 732 /* per UPnP spec, keep IP packet time to live (TTL) small */ 733 unsigned char ttl = 4; 734 int sd; 735 736 sd = socket(AF_INET, SOCK_DGRAM, 0); 737 if (sd < 0 || 738 fcntl(sd, F_SETFL, O_NONBLOCK) != 0 || 739 setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on))) 740 goto fail; 741 os_memset(&addr, 0, sizeof(addr)); 742 addr.sin_family = AF_INET; 743 addr.sin_addr.s_addr = htonl(INADDR_ANY); 744 addr.sin_port = htons(UPNP_MULTICAST_PORT); 745 if (bind(sd, (struct sockaddr *) &addr, sizeof(addr))) 746 goto fail; 747 os_memset(&mcast_addr, 0, sizeof(mcast_addr)); 748 mcast_addr.imr_interface.s_addr = htonl(INADDR_ANY); 749 mcast_addr.imr_multiaddr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS); 750 if (setsockopt(sd, IPPROTO_IP, IP_ADD_MEMBERSHIP, 751 (char *) &mcast_addr, sizeof(mcast_addr)) || 752 setsockopt(sd, IPPROTO_IP, IP_MULTICAST_TTL, 753 &ttl, sizeof(ttl))) 754 goto fail; 755 756 return sd; 757 758 fail: 759 if (sd >= 0) 760 close(sd); 761 return -1; 762 } 763 764 765 /** 766 * ssdp_listener_start - Set up for receiving discovery (UDP) packets 767 * @sm: WPS UPnP state machine from upnp_wps_device_init() 768 * Returns: 0 on success, -1 on failure 769 * 770 * The SSDP listener is stopped by calling ssdp_listener_stop(). 771 */ 772 int ssdp_listener_start(struct upnp_wps_device_sm *sm) 773 { 774 sm->ssdp_sd = ssdp_listener_open(); 775 776 if (eloop_register_sock(sm->ssdp_sd, EVENT_TYPE_READ, 777 ssdp_listener_handler, NULL, sm)) 778 goto fail; 779 sm->ssdp_sd_registered = 1; 780 return 0; 781 782 fail: 783 /* Error */ 784 wpa_printf(MSG_ERROR, "WPS UPnP: ssdp_listener_start failed"); 785 ssdp_listener_stop(sm); 786 return -1; 787 } 788 789 790 /** 791 * add_ssdp_network - Add routing entry for SSDP 792 * @net_if: Selected network interface name 793 * Returns: 0 on success, -1 on failure 794 * 795 * This function assures that the multicast address will be properly 796 * handled by Linux networking code (by a modification to routing tables). 797 * This must be done per network interface. It really only needs to be done 798 * once after booting up, but it does not hurt to call this more frequently 799 * "to be safe". 800 */ 801 int add_ssdp_network(const char *net_if) 802 { 803 #ifdef __linux__ 804 int ret = -1; 805 int sock = -1; 806 struct rtentry rt; 807 struct sockaddr_in *sin; 808 809 if (!net_if) 810 goto fail; 811 812 os_memset(&rt, 0, sizeof(rt)); 813 sock = socket(AF_INET, SOCK_DGRAM, 0); 814 if (sock < 0) 815 goto fail; 816 817 rt.rt_dev = (char *) net_if; 818 sin = aliasing_hide_typecast(&rt.rt_dst, struct sockaddr_in); 819 sin->sin_family = AF_INET; 820 sin->sin_port = 0; 821 sin->sin_addr.s_addr = inet_addr(SSDP_TARGET); 822 sin = aliasing_hide_typecast(&rt.rt_genmask, struct sockaddr_in); 823 sin->sin_family = AF_INET; 824 sin->sin_port = 0; 825 sin->sin_addr.s_addr = inet_addr(SSDP_NETMASK); 826 rt.rt_flags = RTF_UP; 827 if (ioctl(sock, SIOCADDRT, &rt) < 0) { 828 if (errno == EPERM) { 829 wpa_printf(MSG_DEBUG, "add_ssdp_network: No " 830 "permissions to add routing table entry"); 831 /* Continue to allow testing as non-root */ 832 } else if (errno != EEXIST) { 833 wpa_printf(MSG_INFO, "add_ssdp_network() ioctl errno " 834 "%d (%s)", errno, strerror(errno)); 835 goto fail; 836 } 837 } 838 839 ret = 0; 840 841 fail: 842 if (sock >= 0) 843 close(sock); 844 845 return ret; 846 #else /* __linux__ */ 847 return 0; 848 #endif /* __linux__ */ 849 } 850 851 852 int ssdp_open_multicast_sock(u32 ip_addr, const char *forced_ifname) 853 { 854 int sd; 855 /* per UPnP-arch-DeviceArchitecture, 1. Discovery, keep IP packet 856 * time to live (TTL) small */ 857 unsigned char ttl = 4; 858 859 sd = socket(AF_INET, SOCK_DGRAM, 0); 860 if (sd < 0) 861 return -1; 862 863 if (forced_ifname) { 864 #ifdef __linux__ 865 struct ifreq req; 866 os_memset(&req, 0, sizeof(req)); 867 os_strlcpy(req.ifr_name, forced_ifname, sizeof(req.ifr_name)); 868 if (setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, &req, 869 sizeof(req)) < 0) { 870 wpa_printf(MSG_INFO, "WPS UPnP: Failed to bind " 871 "multicast socket to ifname %s: %s", 872 forced_ifname, strerror(errno)); 873 close(sd); 874 return -1; 875 } 876 #endif /* __linux__ */ 877 } 878 879 #if 0 /* maybe ok if we sometimes block on writes */ 880 if (fcntl(sd, F_SETFL, O_NONBLOCK) != 0) { 881 close(sd); 882 return -1; 883 } 884 #endif 885 886 if (setsockopt(sd, IPPROTO_IP, IP_MULTICAST_IF, 887 &ip_addr, sizeof(ip_addr))) { 888 wpa_printf(MSG_DEBUG, "WPS: setsockopt(IP_MULTICAST_IF) %x: " 889 "%d (%s)", ip_addr, errno, strerror(errno)); 890 close(sd); 891 return -1; 892 } 893 if (setsockopt(sd, IPPROTO_IP, IP_MULTICAST_TTL, 894 &ttl, sizeof(ttl))) { 895 wpa_printf(MSG_DEBUG, "WPS: setsockopt(IP_MULTICAST_TTL): " 896 "%d (%s)", errno, strerror(errno)); 897 close(sd); 898 return -1; 899 } 900 901 #if 0 /* not needed, because we don't receive using multicast_sd */ 902 { 903 struct ip_mreq mreq; 904 mreq.imr_multiaddr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS); 905 mreq.imr_interface.s_addr = ip_addr; 906 wpa_printf(MSG_DEBUG, "WPS UPnP: Multicast addr 0x%x if addr " 907 "0x%x", 908 mreq.imr_multiaddr.s_addr, 909 mreq.imr_interface.s_addr); 910 if (setsockopt(sd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, 911 sizeof(mreq))) { 912 wpa_printf(MSG_ERROR, 913 "WPS UPnP: setsockopt " 914 "IP_ADD_MEMBERSHIP errno %d (%s)", 915 errno, strerror(errno)); 916 close(sd); 917 return -1; 918 } 919 } 920 #endif /* not needed */ 921 922 /* 923 * TODO: What about IP_MULTICAST_LOOP? It seems to be on by default? 924 * which aids debugging I suppose but isn't really necessary? 925 */ 926 927 return sd; 928 } 929 930 931 /** 932 * ssdp_open_multicast - Open socket for sending multicast SSDP messages 933 * @sm: WPS UPnP state machine from upnp_wps_device_init() 934 * Returns: 0 on success, -1 on failure 935 */ 936 int ssdp_open_multicast(struct upnp_wps_device_sm *sm) 937 { 938 sm->multicast_sd = ssdp_open_multicast_sock(sm->ip_addr, NULL); 939 if (sm->multicast_sd < 0) 940 return -1; 941 return 0; 942 } 943