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