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 return -1; 880 if (setsockopt(sd, IPPROTO_IP, IP_MULTICAST_TTL, 881 &ttl, sizeof(ttl))) 882 return -1; 883 884 #if 0 /* not needed, because we don't receive using multicast_sd */ 885 { 886 struct ip_mreq mreq; 887 mreq.imr_multiaddr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS); 888 mreq.imr_interface.s_addr = ip_addr; 889 wpa_printf(MSG_DEBUG, "WPS UPnP: Multicast addr 0x%x if addr " 890 "0x%x", 891 mreq.imr_multiaddr.s_addr, 892 mreq.imr_interface.s_addr); 893 if (setsockopt(sd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, 894 sizeof(mreq))) { 895 wpa_printf(MSG_ERROR, 896 "WPS UPnP: setsockopt " 897 "IP_ADD_MEMBERSHIP errno %d (%s)", 898 errno, strerror(errno)); 899 return -1; 900 } 901 } 902 #endif /* not needed */ 903 904 /* 905 * TODO: What about IP_MULTICAST_LOOP? It seems to be on by default? 906 * which aids debugging I suppose but isn't really necessary? 907 */ 908 909 return sd; 910 } 911 912 913 /** 914 * ssdp_open_multicast - Open socket for sending multicast SSDP messages 915 * @sm: WPS UPnP state machine from upnp_wps_device_init() 916 * Returns: 0 on success, -1 on failure 917 */ 918 int ssdp_open_multicast(struct upnp_wps_device_sm *sm) 919 { 920 sm->multicast_sd = ssdp_open_multicast_sock(sm->ip_addr); 921 if (sm->multicast_sd < 0) 922 return -1; 923 return 0; 924 } 925