1 /* $OpenBSD: getaddrinfo_async.c,v 1.51 2017/02/21 07:28:28 eric Exp $ */ 2 /* 3 * Copyright (c) 2012 Eric Faurot <eric@openbsd.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include <sys/types.h> 19 #include <sys/socket.h> 20 #include <sys/uio.h> 21 #include <netinet/in.h> 22 #include <arpa/nameser.h> 23 #include <net/if.h> 24 #include <netdb.h> 25 26 #include <asr.h> 27 #include <errno.h> 28 #include <ifaddrs.h> 29 #include <resolv.h> 30 #include <stdlib.h> 31 #include <string.h> 32 #include <unistd.h> 33 #include <limits.h> 34 35 #include "asr_private.h" 36 37 struct match { 38 int family; 39 int socktype; 40 int protocol; 41 }; 42 43 static int getaddrinfo_async_run(struct asr_query *, struct asr_result *); 44 static int get_port(const char *, const char *, int); 45 static int iter_family(struct asr_query *, int); 46 static int addrinfo_add(struct asr_query *, const struct sockaddr *, const char *); 47 static int addrinfo_from_file(struct asr_query *, int, FILE *); 48 static int addrinfo_from_pkt(struct asr_query *, char *, size_t); 49 static int addrconfig_setup(struct asr_query *); 50 51 static const struct match matches[] = { 52 { PF_INET, SOCK_DGRAM, IPPROTO_UDP }, 53 { PF_INET, SOCK_STREAM, IPPROTO_TCP }, 54 { PF_INET, SOCK_RAW, 0 }, 55 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP }, 56 { PF_INET6, SOCK_STREAM, IPPROTO_TCP }, 57 { PF_INET6, SOCK_RAW, 0 }, 58 { -1, 0, 0, }, 59 }; 60 61 #define MATCH_FAMILY(a, b) ((a) == matches[(b)].family || (a) == PF_UNSPEC) 62 #define MATCH_PROTO(a, b) ((a) == matches[(b)].protocol || (a) == 0 || matches[(b)].protocol == 0) 63 /* Do not match SOCK_RAW unless explicitely specified */ 64 #define MATCH_SOCKTYPE(a, b) ((a) == matches[(b)].socktype || ((a) == 0 && \ 65 matches[(b)].socktype != SOCK_RAW)) 66 67 enum { 68 DOM_INIT, 69 DOM_DOMAIN, 70 DOM_DONE 71 }; 72 73 struct asr_query * 74 getaddrinfo_async(const char *hostname, const char *servname, 75 const struct addrinfo *hints, void *asr) 76 { 77 struct asr_ctx *ac; 78 struct asr_query *as; 79 80 if (hints == NULL || (hints->ai_flags & AI_NUMERICHOST) == 0) 81 ac = _asr_use_resolver(asr); 82 else 83 ac = _asr_no_resolver(); 84 if ((as = _asr_async_new(ac, ASR_GETADDRINFO)) == NULL) 85 goto abort; /* errno set */ 86 as->as_run = getaddrinfo_async_run; 87 88 if (hostname) { 89 if ((as->as.ai.hostname = strdup(hostname)) == NULL) 90 goto abort; /* errno set */ 91 } 92 if (servname && (as->as.ai.servname = strdup(servname)) == NULL) 93 goto abort; /* errno set */ 94 if (hints) 95 memmove(&as->as.ai.hints, hints, sizeof *hints); 96 else { 97 memset(&as->as.ai.hints, 0, sizeof as->as.ai.hints); 98 as->as.ai.hints.ai_family = PF_UNSPEC; 99 as->as.ai.hints.ai_flags = AI_ADDRCONFIG; 100 } 101 102 _asr_ctx_unref(ac); 103 return (as); 104 abort: 105 if (as) 106 _asr_async_free(as); 107 _asr_ctx_unref(ac); 108 return (NULL); 109 } 110 DEF_WEAK(getaddrinfo_async); 111 112 static int 113 getaddrinfo_async_run(struct asr_query *as, struct asr_result *ar) 114 { 115 char fqdn[MAXDNAME]; 116 const char *str; 117 struct addrinfo *ai; 118 int i, family, r; 119 FILE *f; 120 union { 121 struct sockaddr sa; 122 struct sockaddr_in sain; 123 struct sockaddr_in6 sain6; 124 } sa; 125 126 next: 127 switch (as->as_state) { 128 129 case ASR_STATE_INIT: 130 131 /* 132 * First, make sure the parameters are valid. 133 */ 134 135 as->as_count = 0; 136 137 if (as->as.ai.hostname == NULL && 138 as->as.ai.servname == NULL) { 139 ar->ar_gai_errno = EAI_NONAME; 140 async_set_state(as, ASR_STATE_HALT); 141 break; 142 } 143 144 if (as->as.ai.hostname && as->as.ai.hostname[0] == '\0') { 145 ar->ar_gai_errno = EAI_NODATA; 146 async_set_state(as, ASR_STATE_HALT); 147 break; 148 } 149 150 ai = &as->as.ai.hints; 151 152 if (ai->ai_addrlen || 153 ai->ai_canonname || 154 ai->ai_addr || 155 ai->ai_next) { 156 ar->ar_gai_errno = EAI_BADHINTS; 157 async_set_state(as, ASR_STATE_HALT); 158 break; 159 } 160 161 if (ai->ai_flags & ~AI_MASK || 162 (ai->ai_flags & AI_CANONNAME && ai->ai_flags & AI_FQDN)) { 163 ar->ar_gai_errno = EAI_BADFLAGS; 164 async_set_state(as, ASR_STATE_HALT); 165 break; 166 } 167 168 if (ai->ai_family != PF_UNSPEC && 169 ai->ai_family != PF_INET && 170 ai->ai_family != PF_INET6) { 171 ar->ar_gai_errno = EAI_FAMILY; 172 async_set_state(as, ASR_STATE_HALT); 173 break; 174 } 175 176 if (ai->ai_socktype && 177 ai->ai_socktype != SOCK_DGRAM && 178 ai->ai_socktype != SOCK_STREAM && 179 ai->ai_socktype != SOCK_RAW) { 180 ar->ar_gai_errno = EAI_SOCKTYPE; 181 async_set_state(as, ASR_STATE_HALT); 182 break; 183 } 184 185 if (ai->ai_socktype == SOCK_RAW && 186 get_port(as->as.ai.servname, NULL, 1) != 0) { 187 ar->ar_gai_errno = EAI_SERVICE; 188 async_set_state(as, ASR_STATE_HALT); 189 break; 190 } 191 192 /* Restrict result set to configured address families */ 193 if (ai->ai_flags & AI_ADDRCONFIG) { 194 if (addrconfig_setup(as) == -1) { 195 ar->ar_errno = errno; 196 ar->ar_gai_errno = EAI_SYSTEM; 197 async_set_state(as, ASR_STATE_HALT); 198 break; 199 } 200 } 201 202 /* Make sure there is at least a valid combination */ 203 for (i = 0; matches[i].family != -1; i++) 204 if (MATCH_FAMILY(ai->ai_family, i) && 205 MATCH_SOCKTYPE(ai->ai_socktype, i) && 206 MATCH_PROTO(ai->ai_protocol, i)) 207 break; 208 if (matches[i].family == -1) { 209 ar->ar_gai_errno = EAI_BADHINTS; 210 async_set_state(as, ASR_STATE_HALT); 211 break; 212 } 213 214 if (ai->ai_protocol == 0 || ai->ai_protocol == IPPROTO_UDP) 215 as->as.ai.port_udp = get_port(as->as.ai.servname, "udp", 216 as->as.ai.hints.ai_flags & AI_NUMERICSERV); 217 if (ai->ai_protocol == 0 || ai->ai_protocol == IPPROTO_TCP) 218 as->as.ai.port_tcp = get_port(as->as.ai.servname, "tcp", 219 as->as.ai.hints.ai_flags & AI_NUMERICSERV); 220 if (as->as.ai.port_tcp == -2 || as->as.ai.port_udp == -2 || 221 (as->as.ai.port_tcp == -1 && as->as.ai.port_udp == -1) || 222 (ai->ai_protocol && (as->as.ai.port_udp == -1 || 223 as->as.ai.port_tcp == -1))) { 224 ar->ar_gai_errno = EAI_SERVICE; 225 async_set_state(as, ASR_STATE_HALT); 226 break; 227 } 228 229 ar->ar_gai_errno = 0; 230 231 /* If hostname is NULL, use local address */ 232 if (as->as.ai.hostname == NULL) { 233 for (family = iter_family(as, 1); 234 family != -1; 235 family = iter_family(as, 0)) { 236 /* 237 * We could use statically built sockaddrs for 238 * those, rather than parsing over and over. 239 */ 240 if (family == PF_INET) 241 str = (ai->ai_flags & AI_PASSIVE) ? \ 242 "0.0.0.0" : "127.0.0.1"; 243 else /* PF_INET6 */ 244 str = (ai->ai_flags & AI_PASSIVE) ? \ 245 "::" : "::1"; 246 /* This can't fail */ 247 _asr_sockaddr_from_str(&sa.sa, family, str); 248 if ((r = addrinfo_add(as, &sa.sa, NULL))) { 249 ar->ar_gai_errno = r; 250 break; 251 } 252 } 253 if (ar->ar_gai_errno == 0 && as->as_count == 0) { 254 ar->ar_gai_errno = EAI_NODATA; 255 } 256 async_set_state(as, ASR_STATE_HALT); 257 break; 258 } 259 260 /* Try numeric addresses first */ 261 for (family = iter_family(as, 1); 262 family != -1; 263 family = iter_family(as, 0)) { 264 265 if (_asr_sockaddr_from_str(&sa.sa, family, 266 as->as.ai.hostname) == -1) 267 continue; 268 269 if ((r = addrinfo_add(as, &sa.sa, NULL))) 270 ar->ar_gai_errno = r; 271 break; 272 } 273 if (ar->ar_gai_errno || as->as_count) { 274 async_set_state(as, ASR_STATE_HALT); 275 break; 276 } 277 278 if (ai->ai_flags & AI_NUMERICHOST) { 279 ar->ar_gai_errno = EAI_NONAME; 280 async_set_state(as, ASR_STATE_HALT); 281 break; 282 } 283 284 async_set_state(as, ASR_STATE_NEXT_DB); 285 break; 286 287 case ASR_STATE_NEXT_DB: 288 if (_asr_iter_db(as) == -1) { 289 async_set_state(as, ASR_STATE_NOT_FOUND); 290 break; 291 } 292 as->as_family_idx = 0; 293 async_set_state(as, ASR_STATE_SAME_DB); 294 break; 295 296 case ASR_STATE_NEXT_FAMILY: 297 as->as_family_idx += 1; 298 if (as->as.ai.hints.ai_family != AF_UNSPEC || 299 AS_FAMILY(as) == -1) { 300 /* The family was specified, or we have tried all 301 * families with this DB. 302 */ 303 if (as->as_count) { 304 ar->ar_gai_errno = 0; 305 async_set_state(as, ASR_STATE_HALT); 306 } else 307 async_set_state(as, ASR_STATE_NEXT_DOMAIN); 308 break; 309 } 310 async_set_state(as, ASR_STATE_SAME_DB); 311 break; 312 313 case ASR_STATE_NEXT_DOMAIN: 314 /* domain search is only for dns */ 315 if (AS_DB(as) != ASR_DB_DNS) { 316 async_set_state(as, ASR_STATE_NEXT_DB); 317 break; 318 } 319 as->as_family_idx = 0; 320 321 free(as->as.ai.fqdn); 322 as->as.ai.fqdn = NULL; 323 r = _asr_iter_domain(as, as->as.ai.hostname, fqdn, sizeof(fqdn)); 324 if (r == -1) { 325 async_set_state(as, ASR_STATE_NEXT_DB); 326 break; 327 } 328 if (r == 0) { 329 ar->ar_gai_errno = EAI_FAIL; 330 async_set_state(as, ASR_STATE_HALT); 331 break; 332 } 333 as->as.ai.fqdn = strdup(fqdn); 334 if (as->as.ai.fqdn == NULL) { 335 ar->ar_gai_errno = EAI_MEMORY; 336 async_set_state(as, ASR_STATE_HALT); 337 } 338 339 async_set_state(as, ASR_STATE_SAME_DB); 340 break; 341 342 case ASR_STATE_SAME_DB: 343 /* query the current DB again */ 344 switch (AS_DB(as)) { 345 case ASR_DB_DNS: 346 if (as->as.ai.fqdn == NULL) { 347 /* First try, initialize domain iteration */ 348 as->as_dom_flags = 0; 349 as->as_dom_step = DOM_INIT; 350 async_set_state(as, ASR_STATE_NEXT_DOMAIN); 351 break; 352 } 353 354 family = (as->as.ai.hints.ai_family == AF_UNSPEC) ? 355 AS_FAMILY(as) : as->as.ai.hints.ai_family; 356 357 if (family == AF_INET && 358 as->as.ai.flags & ASYNC_NO_INET) { 359 async_set_state(as, ASR_STATE_NEXT_FAMILY); 360 break; 361 } else if (family == AF_INET6 && 362 as->as.ai.flags & ASYNC_NO_INET6) { 363 async_set_state(as, ASR_STATE_NEXT_FAMILY); 364 break; 365 } 366 367 as->as.ai.subq = _res_query_async_ctx(as->as.ai.fqdn, 368 C_IN, (family == AF_INET6) ? T_AAAA : T_A, 369 as->as_ctx); 370 371 if (as->as.ai.subq == NULL) { 372 if (errno == ENOMEM) 373 ar->ar_gai_errno = EAI_MEMORY; 374 else 375 ar->ar_gai_errno = EAI_FAIL; 376 async_set_state(as, ASR_STATE_HALT); 377 break; 378 } 379 async_set_state(as, ASR_STATE_SUBQUERY); 380 break; 381 382 case ASR_DB_FILE: 383 f = fopen(_PATH_HOSTS, "re"); 384 if (f == NULL) { 385 async_set_state(as, ASR_STATE_NEXT_DB); 386 break; 387 } 388 family = (as->as.ai.hints.ai_family == AF_UNSPEC) ? 389 AS_FAMILY(as) : as->as.ai.hints.ai_family; 390 391 r = addrinfo_from_file(as, family, f); 392 if (r == -1) { 393 if (errno == ENOMEM) 394 ar->ar_gai_errno = EAI_MEMORY; 395 else 396 ar->ar_gai_errno = EAI_FAIL; 397 async_set_state(as, ASR_STATE_HALT); 398 } else 399 async_set_state(as, ASR_STATE_NEXT_FAMILY); 400 fclose(f); 401 break; 402 403 default: 404 async_set_state(as, ASR_STATE_NEXT_DB); 405 } 406 break; 407 408 case ASR_STATE_SUBQUERY: 409 if ((r = asr_run(as->as.ai.subq, ar)) == ASYNC_COND) 410 return (ASYNC_COND); 411 412 as->as.ai.subq = NULL; 413 414 if (ar->ar_datalen == -1) { 415 async_set_state(as, ASR_STATE_NEXT_FAMILY); 416 break; 417 } 418 419 r = addrinfo_from_pkt(as, ar->ar_data, ar->ar_datalen); 420 if (r == -1) { 421 if (errno == ENOMEM) 422 ar->ar_gai_errno = EAI_MEMORY; 423 else 424 ar->ar_gai_errno = EAI_FAIL; 425 async_set_state(as, ASR_STATE_HALT); 426 } else 427 async_set_state(as, ASR_STATE_NEXT_FAMILY); 428 free(ar->ar_data); 429 break; 430 431 case ASR_STATE_NOT_FOUND: 432 /* No result found. Maybe we can try again. */ 433 if (as->as.ai.flags & ASYNC_AGAIN) 434 ar->ar_gai_errno = EAI_AGAIN; 435 else 436 ar->ar_gai_errno = EAI_NODATA; 437 async_set_state(as, ASR_STATE_HALT); 438 break; 439 440 case ASR_STATE_HALT: 441 if (ar->ar_gai_errno == 0) { 442 ar->ar_count = as->as_count; 443 ar->ar_addrinfo = as->as.ai.aifirst; 444 as->as.ai.aifirst = NULL; 445 } else { 446 ar->ar_count = 0; 447 ar->ar_addrinfo = NULL; 448 } 449 return (ASYNC_DONE); 450 451 default: 452 ar->ar_errno = EOPNOTSUPP; 453 ar->ar_gai_errno = EAI_SYSTEM; 454 async_set_state(as, ASR_STATE_HALT); 455 break; 456 } 457 goto next; 458 } 459 460 /* 461 * Retreive the port number for the service name "servname" and 462 * the protocol "proto". 463 */ 464 static int 465 get_port(const char *servname, const char *proto, int numonly) 466 { 467 struct servent se; 468 struct servent_data sed; 469 int port, r; 470 const char *e; 471 472 if (servname == NULL) 473 return (0); 474 475 e = NULL; 476 port = strtonum(servname, 0, USHRT_MAX, &e); 477 if (e == NULL) 478 return (port); 479 if (errno == ERANGE) 480 return (-2); /* invalid */ 481 if (numonly) 482 return (-2); 483 484 memset(&sed, 0, sizeof(sed)); 485 r = getservbyname_r(servname, proto, &se, &sed); 486 port = ntohs(se.s_port); 487 endservent_r(&sed); 488 489 if (r == -1) 490 return (-1); /* not found */ 491 492 return (port); 493 } 494 495 /* 496 * Iterate over the address families that are to be queried. Use the 497 * list on the async context, unless a specific family was given in hints. 498 */ 499 static int 500 iter_family(struct asr_query *as, int first) 501 { 502 if (first) { 503 as->as_family_idx = 0; 504 if (as->as.ai.hints.ai_family != PF_UNSPEC) 505 return as->as.ai.hints.ai_family; 506 return AS_FAMILY(as); 507 } 508 509 if (as->as.ai.hints.ai_family != PF_UNSPEC) 510 return (-1); 511 512 as->as_family_idx++; 513 514 return AS_FAMILY(as); 515 } 516 517 /* 518 * Use the sockaddr at "sa" to extend the result list on the "as" context, 519 * with the specified canonical name "cname". This function adds one 520 * entry per protocol/socktype match. 521 */ 522 static int 523 addrinfo_add(struct asr_query *as, const struct sockaddr *sa, const char *cname) 524 { 525 struct addrinfo *ai; 526 int i, port, proto; 527 528 for (i = 0; matches[i].family != -1; i++) { 529 if (matches[i].family != sa->sa_family || 530 !MATCH_SOCKTYPE(as->as.ai.hints.ai_socktype, i) || 531 !MATCH_PROTO(as->as.ai.hints.ai_protocol, i)) 532 continue; 533 534 proto = as->as.ai.hints.ai_protocol; 535 if (!proto) 536 proto = matches[i].protocol; 537 538 if (proto == IPPROTO_TCP) 539 port = as->as.ai.port_tcp; 540 else if (proto == IPPROTO_UDP) 541 port = as->as.ai.port_udp; 542 else 543 port = 0; 544 545 /* servname specified, but not defined for this protocol */ 546 if (port == -1) 547 continue; 548 549 ai = calloc(1, sizeof(*ai) + sa->sa_len); 550 if (ai == NULL) 551 return (EAI_MEMORY); 552 ai->ai_family = sa->sa_family; 553 ai->ai_socktype = matches[i].socktype; 554 ai->ai_protocol = proto; 555 ai->ai_flags = as->as.ai.hints.ai_flags; 556 ai->ai_addrlen = sa->sa_len; 557 ai->ai_addr = (void *)(ai + 1); 558 if (cname && 559 as->as.ai.hints.ai_flags & (AI_CANONNAME | AI_FQDN)) { 560 if ((ai->ai_canonname = strdup(cname)) == NULL) { 561 free(ai); 562 return (EAI_MEMORY); 563 } 564 } 565 memmove(ai->ai_addr, sa, sa->sa_len); 566 if (sa->sa_family == PF_INET) 567 ((struct sockaddr_in *)ai->ai_addr)->sin_port = 568 htons(port); 569 else if (sa->sa_family == PF_INET6) 570 ((struct sockaddr_in6 *)ai->ai_addr)->sin6_port = 571 htons(port); 572 573 if (as->as.ai.aifirst == NULL) 574 as->as.ai.aifirst = ai; 575 if (as->as.ai.ailast) 576 as->as.ai.ailast->ai_next = ai; 577 as->as.ai.ailast = ai; 578 as->as_count += 1; 579 } 580 581 return (0); 582 } 583 584 static int 585 addrinfo_from_file(struct asr_query *as, int family, FILE *f) 586 { 587 char *tokens[MAXTOKEN], *c, buf[BUFSIZ + 1]; 588 int n, i; 589 union { 590 struct sockaddr sa; 591 struct sockaddr_in sain; 592 struct sockaddr_in6 sain6; 593 } u; 594 595 for (;;) { 596 n = _asr_parse_namedb_line(f, tokens, MAXTOKEN, buf, sizeof(buf)); 597 if (n == -1) 598 break; /* ignore errors reading the file */ 599 600 for (i = 1; i < n; i++) { 601 if (strcasecmp(as->as.ai.hostname, tokens[i])) 602 continue; 603 if (_asr_sockaddr_from_str(&u.sa, family, tokens[0]) == -1) 604 continue; 605 break; 606 } 607 if (i == n) 608 continue; 609 610 if (as->as.ai.hints.ai_flags & (AI_CANONNAME | AI_FQDN)) 611 c = tokens[1]; 612 else 613 c = NULL; 614 615 if (addrinfo_add(as, &u.sa, c)) 616 return (-1); /* errno set */ 617 } 618 return (0); 619 } 620 621 static int 622 addrinfo_from_pkt(struct asr_query *as, char *pkt, size_t pktlen) 623 { 624 struct asr_unpack p; 625 struct asr_dns_header h; 626 struct asr_dns_query q; 627 struct asr_dns_rr rr; 628 int i; 629 union { 630 struct sockaddr sa; 631 struct sockaddr_in sain; 632 struct sockaddr_in6 sain6; 633 } u; 634 char buf[MAXDNAME], *c; 635 636 _asr_unpack_init(&p, pkt, pktlen); 637 _asr_unpack_header(&p, &h); 638 for (; h.qdcount; h.qdcount--) 639 _asr_unpack_query(&p, &q); 640 641 for (i = 0; i < h.ancount; i++) { 642 _asr_unpack_rr(&p, &rr); 643 if (rr.rr_type != q.q_type || 644 rr.rr_class != q.q_class) 645 continue; 646 647 memset(&u, 0, sizeof u); 648 if (rr.rr_type == T_A) { 649 u.sain.sin_len = sizeof u.sain; 650 u.sain.sin_family = AF_INET; 651 u.sain.sin_addr = rr.rr.in_a.addr; 652 u.sain.sin_port = 0; 653 } else if (rr.rr_type == T_AAAA) { 654 u.sain6.sin6_len = sizeof u.sain6; 655 u.sain6.sin6_family = AF_INET6; 656 u.sain6.sin6_addr = rr.rr.in_aaaa.addr6; 657 u.sain6.sin6_port = 0; 658 } else 659 continue; 660 661 if (as->as.ai.hints.ai_flags & AI_CANONNAME) { 662 _asr_strdname(rr.rr_dname, buf, sizeof buf); 663 buf[strlen(buf) - 1] = '\0'; 664 c = res_hnok(buf) ? buf : NULL; 665 } else if (as->as.ai.hints.ai_flags & AI_FQDN) 666 c = as->as.ai.fqdn; 667 else 668 c = NULL; 669 670 if (addrinfo_add(as, &u.sa, c)) 671 return (-1); /* errno set */ 672 } 673 return (0); 674 } 675 676 static int 677 addrconfig_setup(struct asr_query *as) 678 { 679 struct ifaddrs *ifa, *ifa0; 680 struct sockaddr_in *sinp; 681 struct sockaddr_in6 *sin6p; 682 683 if (getifaddrs(&ifa0) == -1) 684 return (-1); 685 686 as->as.ai.flags |= ASYNC_NO_INET | ASYNC_NO_INET6; 687 688 for (ifa = ifa0; ifa != NULL; ifa = ifa->ifa_next) { 689 if (ifa->ifa_addr == NULL) 690 continue; 691 692 switch (ifa->ifa_addr->sa_family) { 693 case PF_INET: 694 sinp = (struct sockaddr_in *)ifa->ifa_addr; 695 696 if (sinp->sin_addr.s_addr == htonl(INADDR_LOOPBACK)) 697 continue; 698 699 as->as.ai.flags &= ~ASYNC_NO_INET; 700 break; 701 case PF_INET6: 702 sin6p = (struct sockaddr_in6 *)ifa->ifa_addr; 703 704 if (IN6_IS_ADDR_LOOPBACK(&sin6p->sin6_addr)) 705 continue; 706 707 if (IN6_IS_ADDR_LINKLOCAL(&sin6p->sin6_addr)) 708 continue; 709 710 as->as.ai.flags &= ~ASYNC_NO_INET6; 711 break; 712 } 713 } 714 715 freeifaddrs(ifa0); 716 717 return (0); 718 } 719