1 /* $OpenBSD: getaddrinfo_async.c,v 1.34 2015/02/14 20:15:05 jca 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 <err.h> 28 #include <errno.h> 29 #include <ifaddrs.h> 30 #include <resolv.h> /* for res_hnok */ 31 #include <stdlib.h> 32 #include <string.h> 33 #include <unistd.h> 34 #include <limits.h> 35 36 #ifdef YP 37 #include <rpc/rpc.h> 38 #include <rpcsvc/yp.h> 39 #include <rpcsvc/ypclnt.h> 40 #include "ypinternal.h" 41 #endif 42 43 #include "asr_private.h" 44 45 struct match { 46 int family; 47 int socktype; 48 int protocol; 49 }; 50 51 static int getaddrinfo_async_run(struct asr_query *, struct asr_result *); 52 static int get_port(const char *, const char *, int); 53 static int iter_family(struct asr_query *, int); 54 static int iter_domain(struct asr_query *, const char *, char *, size_t); 55 static int addrinfo_add(struct asr_query *, const struct sockaddr *, const char *); 56 static int addrinfo_from_file(struct asr_query *, int, FILE *); 57 static int addrinfo_from_pkt(struct asr_query *, char *, size_t); 58 #ifdef YP 59 static int addrinfo_from_yp(struct asr_query *, int, char *); 60 #endif 61 62 static const struct match matches[] = { 63 { PF_INET, SOCK_DGRAM, IPPROTO_UDP }, 64 { PF_INET, SOCK_STREAM, IPPROTO_TCP }, 65 { PF_INET, SOCK_RAW, 0 }, 66 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP }, 67 { PF_INET6, SOCK_STREAM, IPPROTO_TCP }, 68 { PF_INET6, SOCK_RAW, 0 }, 69 { -1, 0, 0, }, 70 }; 71 72 #define MATCH_FAMILY(a, b) ((a) == matches[(b)].family || (a) == PF_UNSPEC) 73 #define MATCH_PROTO(a, b) ((a) == matches[(b)].protocol || (a) == 0 || matches[(b)].protocol == 0) 74 /* Do not match SOCK_RAW unless explicitely specified */ 75 #define MATCH_SOCKTYPE(a, b) ((a) == matches[(b)].socktype || ((a) == 0 && \ 76 matches[(b)].socktype != SOCK_RAW)) 77 78 enum { 79 DOM_INIT, 80 DOM_DOMAIN, 81 DOM_DONE 82 }; 83 84 struct asr_query * 85 getaddrinfo_async(const char *hostname, const char *servname, 86 const struct addrinfo *hints, void *asr) 87 { 88 struct asr_ctx *ac; 89 struct asr_query *as; 90 char alias[MAXDNAME]; 91 92 ac = asr_use_resolver(asr); 93 if ((as = asr_async_new(ac, ASR_GETADDRINFO)) == NULL) 94 goto abort; /* errno set */ 95 as->as_run = getaddrinfo_async_run; 96 97 if (hostname) { 98 if (asr_hostalias(ac, hostname, alias, sizeof(alias))) 99 hostname = alias; 100 if ((as->as.ai.hostname = strdup(hostname)) == NULL) 101 goto abort; /* errno set */ 102 } 103 if (servname && (as->as.ai.servname = strdup(servname)) == NULL) 104 goto abort; /* errno set */ 105 if (hints) 106 memmove(&as->as.ai.hints, hints, sizeof *hints); 107 else { 108 memset(&as->as.ai.hints, 0, sizeof as->as.ai.hints); 109 as->as.ai.hints.ai_family = PF_UNSPEC; 110 as->as.ai.hints.ai_flags = AI_ADDRCONFIG; 111 } 112 113 asr_ctx_unref(ac); 114 return (as); 115 abort: 116 if (as) 117 asr_async_free(as); 118 asr_ctx_unref(ac); 119 return (NULL); 120 } 121 122 static int 123 getaddrinfo_async_run(struct asr_query *as, struct asr_result *ar) 124 { 125 #ifdef YP 126 static char *domain = NULL; 127 char *res; 128 int len; 129 char *name; 130 #endif 131 char fqdn[MAXDNAME]; 132 const char *str; 133 struct addrinfo *ai; 134 int i, family, r; 135 FILE *f; 136 struct ifaddrs *ifa, *ifa0; 137 union { 138 struct sockaddr sa; 139 struct sockaddr_in sain; 140 struct sockaddr_in6 sain6; 141 } sa; 142 143 next: 144 switch (as->as_state) { 145 146 case ASR_STATE_INIT: 147 148 /* 149 * First, make sure the parameters are valid. 150 */ 151 152 as->as_count = 0; 153 154 if (as->as.ai.hostname == NULL && 155 as->as.ai.servname == NULL) { 156 ar->ar_gai_errno = EAI_NONAME; 157 async_set_state(as, ASR_STATE_HALT); 158 break; 159 } 160 161 if (as->as.ai.hostname && as->as.ai.hostname[0] == '\0') { 162 ar->ar_gai_errno = EAI_NODATA; 163 async_set_state(as, ASR_STATE_HALT); 164 break; 165 } 166 167 ai = &as->as.ai.hints; 168 169 if (ai->ai_addrlen || 170 ai->ai_canonname || 171 ai->ai_addr || 172 ai->ai_next) { 173 ar->ar_gai_errno = EAI_BADHINTS; 174 async_set_state(as, ASR_STATE_HALT); 175 break; 176 } 177 178 if (ai->ai_flags & ~AI_MASK || 179 (ai->ai_flags & AI_CANONNAME && ai->ai_flags & AI_FQDN)) { 180 ar->ar_gai_errno = EAI_BADFLAGS; 181 async_set_state(as, ASR_STATE_HALT); 182 break; 183 } 184 185 if (ai->ai_family != PF_UNSPEC && 186 ai->ai_family != PF_INET && 187 ai->ai_family != PF_INET6) { 188 ar->ar_gai_errno = EAI_FAMILY; 189 async_set_state(as, ASR_STATE_HALT); 190 break; 191 } 192 193 if (ai->ai_socktype && 194 ai->ai_socktype != SOCK_DGRAM && 195 ai->ai_socktype != SOCK_STREAM && 196 ai->ai_socktype != SOCK_RAW) { 197 ar->ar_gai_errno = EAI_SOCKTYPE; 198 async_set_state(as, ASR_STATE_HALT); 199 break; 200 } 201 202 if (ai->ai_socktype == SOCK_RAW && 203 get_port(as->as.ai.servname, NULL, 1) != 0) { 204 ar->ar_gai_errno = EAI_SERVICE; 205 async_set_state(as, ASR_STATE_HALT); 206 break; 207 } 208 209 /* Restrict result set to configured address families */ 210 if (ai->ai_flags & AI_ADDRCONFIG) { 211 if (getifaddrs(&ifa0) != 0) { 212 ar->ar_gai_errno = EAI_FAIL; 213 async_set_state(as, ASR_STATE_HALT); 214 break; 215 } 216 217 as->as.ai.flags |= ASYNC_NO_INET | ASYNC_NO_INET6; 218 for (ifa = ifa0; ifa != NULL; ifa = ifa->ifa_next) { 219 if (ifa->ifa_flags & IFF_LOOPBACK) 220 continue; 221 if (ifa->ifa_addr == NULL) 222 continue; 223 if (ifa->ifa_addr->sa_family == PF_INET) 224 as->as.ai.flags &= ~ASYNC_NO_INET; 225 else if (ifa->ifa_addr->sa_family == PF_INET6 && 226 !IN6_IS_ADDR_LINKLOCAL(&((struct 227 sockaddr_in6 *)ifa->ifa_addr)->sin6_addr)) 228 as->as.ai.flags &= ~ASYNC_NO_INET6; 229 } 230 freeifaddrs(ifa0); 231 } 232 233 /* Make sure there is at least a valid combination */ 234 for (i = 0; matches[i].family != -1; i++) 235 if (MATCH_FAMILY(ai->ai_family, i) && 236 MATCH_SOCKTYPE(ai->ai_socktype, i) && 237 MATCH_PROTO(ai->ai_protocol, i)) 238 break; 239 if (matches[i].family == -1) { 240 ar->ar_gai_errno = EAI_BADHINTS; 241 async_set_state(as, ASR_STATE_HALT); 242 break; 243 } 244 245 if (ai->ai_protocol == 0 || ai->ai_protocol == IPPROTO_UDP) 246 as->as.ai.port_udp = get_port(as->as.ai.servname, "udp", 247 as->as.ai.hints.ai_flags & AI_NUMERICSERV); 248 if (ai->ai_protocol == 0 || ai->ai_protocol == IPPROTO_TCP) 249 as->as.ai.port_tcp = get_port(as->as.ai.servname, "tcp", 250 as->as.ai.hints.ai_flags & AI_NUMERICSERV); 251 if (as->as.ai.port_tcp == -2 || as->as.ai.port_udp == -2 || 252 (as->as.ai.port_tcp == -1 && as->as.ai.port_udp == -1) || 253 (ai->ai_protocol && (as->as.ai.port_udp == -1 || 254 as->as.ai.port_tcp == -1))) { 255 ar->ar_gai_errno = EAI_SERVICE; 256 async_set_state(as, ASR_STATE_HALT); 257 break; 258 } 259 260 ar->ar_gai_errno = 0; 261 262 /* If hostname is NULL, use local address */ 263 if (as->as.ai.hostname == NULL) { 264 for (family = iter_family(as, 1); 265 family != -1; 266 family = iter_family(as, 0)) { 267 /* 268 * We could use statically built sockaddrs for 269 * those, rather than parsing over and over. 270 */ 271 if (family == PF_INET) 272 str = (ai->ai_flags & AI_PASSIVE) ? \ 273 "0.0.0.0" : "127.0.0.1"; 274 else /* PF_INET6 */ 275 str = (ai->ai_flags & AI_PASSIVE) ? \ 276 "::" : "::1"; 277 /* This can't fail */ 278 asr_sockaddr_from_str(&sa.sa, family, str); 279 if ((r = addrinfo_add(as, &sa.sa, NULL))) { 280 ar->ar_gai_errno = r; 281 break; 282 } 283 } 284 if (ar->ar_gai_errno == 0 && as->as_count == 0) { 285 ar->ar_gai_errno = EAI_NODATA; 286 } 287 async_set_state(as, ASR_STATE_HALT); 288 break; 289 } 290 291 /* Try numeric addresses first */ 292 for (family = iter_family(as, 1); 293 family != -1; 294 family = iter_family(as, 0)) { 295 296 if (asr_sockaddr_from_str(&sa.sa, family, 297 as->as.ai.hostname) == -1) 298 continue; 299 300 if ((r = addrinfo_add(as, &sa.sa, NULL))) 301 ar->ar_gai_errno = r; 302 break; 303 } 304 if (ar->ar_gai_errno || as->as_count) { 305 async_set_state(as, ASR_STATE_HALT); 306 break; 307 } 308 309 if (ai->ai_flags & AI_NUMERICHOST) { 310 ar->ar_gai_errno = EAI_NONAME; 311 async_set_state(as, ASR_STATE_HALT); 312 break; 313 } 314 315 async_set_state(as, ASR_STATE_NEXT_DB); 316 break; 317 318 case ASR_STATE_NEXT_DB: 319 if (asr_iter_db(as) == -1) { 320 async_set_state(as, ASR_STATE_NOT_FOUND); 321 break; 322 } 323 as->as_family_idx = 0; 324 async_set_state(as, ASR_STATE_SAME_DB); 325 break; 326 327 case ASR_STATE_NEXT_FAMILY: 328 as->as_family_idx += 1; 329 if (as->as.ai.hints.ai_family != AF_UNSPEC || 330 AS_FAMILY(as) == -1) { 331 /* The family was specified, or we have tried all 332 * families with this DB. 333 */ 334 if (as->as_count) { 335 ar->ar_gai_errno = 0; 336 async_set_state(as, ASR_STATE_HALT); 337 } else 338 async_set_state(as, ASR_STATE_NEXT_DOMAIN); 339 break; 340 } 341 async_set_state(as, ASR_STATE_SAME_DB); 342 break; 343 344 case ASR_STATE_NEXT_DOMAIN: 345 /* domain search is only for dns */ 346 if (AS_DB(as) != ASR_DB_DNS) { 347 async_set_state(as, ASR_STATE_NEXT_DB); 348 break; 349 } 350 as->as_family_idx = 0; 351 352 free(as->as.ai.fqdn); 353 as->as.ai.fqdn = NULL; 354 r = iter_domain(as, as->as.ai.hostname, fqdn, sizeof(fqdn)); 355 if (r == -1) { 356 async_set_state(as, ASR_STATE_NEXT_DB); 357 break; 358 } 359 if (r == 0) { 360 ar->ar_gai_errno = EAI_FAIL; 361 async_set_state(as, ASR_STATE_HALT); 362 break; 363 } 364 as->as.ai.fqdn = strdup(fqdn); 365 if (as->as.ai.fqdn == NULL) { 366 ar->ar_gai_errno = EAI_MEMORY; 367 async_set_state(as, ASR_STATE_HALT); 368 } 369 370 async_set_state(as, ASR_STATE_SAME_DB); 371 break; 372 373 case ASR_STATE_SAME_DB: 374 /* query the current DB again */ 375 switch (AS_DB(as)) { 376 case ASR_DB_DNS: 377 if (as->as.ai.fqdn == NULL) { 378 /* First try, initialize domain iteration */ 379 as->as_dom_flags = 0; 380 as->as_dom_step = DOM_INIT; 381 async_set_state(as, ASR_STATE_NEXT_DOMAIN); 382 break; 383 } 384 385 family = (as->as.ai.hints.ai_family == AF_UNSPEC) ? 386 AS_FAMILY(as) : as->as.ai.hints.ai_family; 387 388 if (family == AF_INET && 389 as->as.ai.flags & ASYNC_NO_INET) { 390 async_set_state(as, ASR_STATE_NEXT_FAMILY); 391 break; 392 } else if (family == AF_INET6 && 393 as->as.ai.flags & ASYNC_NO_INET6) { 394 async_set_state(as, ASR_STATE_NEXT_FAMILY); 395 break; 396 } 397 398 as->as.ai.subq = res_query_async_ctx(as->as.ai.fqdn, 399 C_IN, (family == AF_INET6) ? T_AAAA : T_A, 400 as->as_ctx); 401 402 if (as->as.ai.subq == NULL) { 403 if (errno == ENOMEM) 404 ar->ar_gai_errno = EAI_MEMORY; 405 else 406 ar->ar_gai_errno = EAI_FAIL; 407 async_set_state(as, ASR_STATE_HALT); 408 break; 409 } 410 async_set_state(as, ASR_STATE_SUBQUERY); 411 break; 412 413 case ASR_DB_FILE: 414 f = fopen(as->as_ctx->ac_hostfile, "re"); 415 if (f == NULL) { 416 async_set_state(as, ASR_STATE_NEXT_DB); 417 break; 418 } 419 family = (as->as.ai.hints.ai_family == AF_UNSPEC) ? 420 AS_FAMILY(as) : as->as.ai.hints.ai_family; 421 422 r = addrinfo_from_file(as, family, f); 423 if (r == -1) { 424 if (errno == ENOMEM) 425 ar->ar_gai_errno = EAI_MEMORY; 426 else 427 ar->ar_gai_errno = EAI_FAIL; 428 async_set_state(as, ASR_STATE_HALT); 429 } else 430 async_set_state(as, ASR_STATE_NEXT_FAMILY); 431 fclose(f); 432 break; 433 434 #ifdef YP 435 case ASR_DB_YP: 436 if (!domain && _yp_check(&domain) == 0) { 437 async_set_state(as, ASR_STATE_NEXT_DB); 438 break; 439 } 440 family = (as->as.ai.hints.ai_family == AF_UNSPEC) ? 441 AS_FAMILY(as) : as->as.ai.hints.ai_family; 442 443 name = as->as.ai.hostname; 444 445 /* XXX 446 * ipnodes.byname could also contain IPv4 address 447 */ 448 r = yp_match(domain, (family == AF_INET6) ? 449 "ipnodes.byname" : "hosts.byname", 450 name, strlen(name), &res, &len); 451 if (r == 0) { 452 r = addrinfo_from_yp(as, family, res); 453 free(res); 454 if (r == -1) { 455 if (errno == ENOMEM) 456 ar->ar_gai_errno = EAI_MEMORY; 457 else 458 ar->ar_gai_errno = EAI_FAIL; 459 async_set_state(as, ASR_STATE_HALT); 460 break; 461 } 462 } 463 async_set_state(as, ASR_STATE_NEXT_FAMILY); 464 break; 465 #endif 466 default: 467 async_set_state(as, ASR_STATE_NEXT_DB); 468 } 469 break; 470 471 case ASR_STATE_SUBQUERY: 472 if ((r = asr_run(as->as.ai.subq, ar)) == ASYNC_COND) 473 return (ASYNC_COND); 474 475 as->as.ai.subq = NULL; 476 477 if (ar->ar_datalen == -1) { 478 async_set_state(as, ASR_STATE_NEXT_FAMILY); 479 break; 480 } 481 482 r = addrinfo_from_pkt(as, ar->ar_data, ar->ar_datalen); 483 if (r == -1) { 484 if (errno == ENOMEM) 485 ar->ar_gai_errno = EAI_MEMORY; 486 else 487 ar->ar_gai_errno = EAI_FAIL; 488 async_set_state(as, ASR_STATE_HALT); 489 } else 490 async_set_state(as, ASR_STATE_NEXT_FAMILY); 491 free(ar->ar_data); 492 break; 493 494 case ASR_STATE_NOT_FOUND: 495 /* No result found. Maybe we can try again. */ 496 if (as->as.ai.flags & ASYNC_AGAIN) 497 ar->ar_gai_errno = EAI_AGAIN; 498 else 499 ar->ar_gai_errno = EAI_NODATA; 500 async_set_state(as, ASR_STATE_HALT); 501 break; 502 503 case ASR_STATE_HALT: 504 if (ar->ar_gai_errno == 0) { 505 ar->ar_count = as->as_count; 506 ar->ar_addrinfo = as->as.ai.aifirst; 507 as->as.ai.aifirst = NULL; 508 } else { 509 ar->ar_count = 0; 510 ar->ar_addrinfo = NULL; 511 } 512 return (ASYNC_DONE); 513 514 default: 515 ar->ar_errno = EOPNOTSUPP; 516 ar->ar_gai_errno = EAI_SYSTEM; 517 async_set_state(as, ASR_STATE_HALT); 518 break; 519 } 520 goto next; 521 } 522 523 /* 524 * Retreive the port number for the service name "servname" and 525 * the protocol "proto". 526 */ 527 static int 528 get_port(const char *servname, const char *proto, int numonly) 529 { 530 struct servent se; 531 struct servent_data sed; 532 int port, r; 533 const char *e; 534 535 if (servname == NULL) 536 return (0); 537 538 e = NULL; 539 port = strtonum(servname, 0, USHRT_MAX, &e); 540 if (e == NULL) 541 return (port); 542 if (errno == ERANGE) 543 return (-2); /* invalid */ 544 if (numonly) 545 return (-2); 546 547 memset(&sed, 0, sizeof(sed)); 548 r = getservbyname_r(servname, proto, &se, &sed); 549 port = ntohs(se.s_port); 550 endservent_r(&sed); 551 552 if (r == -1) 553 return (-1); /* not found */ 554 555 return (port); 556 } 557 558 /* 559 * Iterate over the address families that are to be queried. Use the 560 * list on the async context, unless a specific family was given in hints. 561 */ 562 static int 563 iter_family(struct asr_query *as, int first) 564 { 565 if (first) { 566 as->as_family_idx = 0; 567 if (as->as.ai.hints.ai_family != PF_UNSPEC) 568 return as->as.ai.hints.ai_family; 569 return AS_FAMILY(as); 570 } 571 572 if (as->as.ai.hints.ai_family != PF_UNSPEC) 573 return (-1); 574 575 as->as_family_idx++; 576 577 return AS_FAMILY(as); 578 } 579 580 /* 581 * Concatenate a name and a domain name. The result has no trailing dot. 582 * Return the resulting string length, or 0 in case of error. 583 */ 584 static size_t 585 domcat(const char *name, const char *domain, char *buf, size_t buflen) 586 { 587 size_t r; 588 589 r = asr_make_fqdn(name, domain, buf, buflen); 590 if (r == 0) 591 return (0); 592 buf[r - 1] = '\0'; 593 594 return (r - 1); 595 } 596 597 /* 598 * Implement the search domain strategy. 599 * 600 * XXX duplicate from res_search_async 601 * 602 * This function works as a generator that constructs complete domains in 603 * buffer "buf" of size "len" for the given host name "name", according to the 604 * search rules defined by the resolving context. It is supposed to be called 605 * multiple times (with the same name) to generate the next possible domain 606 * name, if any. 607 * 608 * It returns -1 if all possibilities have been exhausted, 0 if there was an 609 * error generating the next name, or the resulting name length. 610 */ 611 static int 612 iter_domain(struct asr_query *as, const char *name, char * buf, size_t len) 613 { 614 const char *c; 615 int dots; 616 617 switch (as->as_dom_step) { 618 619 case DOM_INIT: 620 /* First call */ 621 622 /* 623 * If "name" is an FQDN, that's the only result and we 624 * don't try anything else. 625 */ 626 if (strlen(name) && name[strlen(name) - 1] == '.') { 627 DPRINT("asr: iter_domain(\"%s\") fqdn\n", name); 628 as->as_dom_flags |= ASYNC_DOM_FQDN; 629 as->as_dom_step = DOM_DONE; 630 return (domcat(name, NULL, buf, len)); 631 } 632 633 /* 634 * Otherwise, we iterate through the specified search domains. 635 */ 636 as->as_dom_step = DOM_DOMAIN; 637 as->as_dom_idx = 0; 638 639 /* 640 * If "name" as enough dots, use it as-is first, as indicated 641 * in resolv.conf(5). 642 */ 643 dots = 0; 644 for (c = name; *c; c++) 645 dots += (*c == '.'); 646 if (dots >= as->as_ctx->ac_ndots) { 647 DPRINT("asr: iter_domain(\"%s\") ndots\n", name); 648 as->as_dom_flags |= ASYNC_DOM_NDOTS; 649 if (strlcpy(buf, name, len) >= len) 650 return (0); 651 return (strlen(buf)); 652 } 653 /* Otherwise, starts using the search domains */ 654 /* FALLTHROUGH */ 655 656 case DOM_DOMAIN: 657 if (as->as_dom_idx < as->as_ctx->ac_domcount) { 658 DPRINT("asr: iter_domain(\"%s\") domain \"%s\"\n", 659 name, as->as_ctx->ac_dom[as->as_dom_idx]); 660 as->as_dom_flags |= ASYNC_DOM_DOMAIN; 661 return (domcat(name, 662 as->as_ctx->ac_dom[as->as_dom_idx++], buf, len)); 663 } 664 665 /* No more domain to try. */ 666 667 as->as_dom_step = DOM_DONE; 668 669 /* 670 * If the name was not tried as an absolute name before, 671 * do it now. 672 */ 673 if (!(as->as_dom_flags & ASYNC_DOM_NDOTS)) { 674 DPRINT("asr: iter_domain(\"%s\") as is\n", name); 675 as->as_dom_flags |= ASYNC_DOM_ASIS; 676 if (strlcpy(buf, name, len) >= len) 677 return (0); 678 return (strlen(buf)); 679 } 680 /* Otherwise, we are done. */ 681 682 case DOM_DONE: 683 default: 684 DPRINT("asr: iter_domain(\"%s\") done\n", name); 685 return (-1); 686 } 687 } 688 689 /* 690 * Use the sockaddr at "sa" to extend the result list on the "as" context, 691 * with the specified canonical name "cname". This function adds one 692 * entry per protocol/socktype match. 693 */ 694 static int 695 addrinfo_add(struct asr_query *as, const struct sockaddr *sa, const char *cname) 696 { 697 struct addrinfo *ai; 698 int i, port, proto; 699 700 for (i = 0; matches[i].family != -1; i++) { 701 if (matches[i].family != sa->sa_family || 702 !MATCH_SOCKTYPE(as->as.ai.hints.ai_socktype, i) || 703 !MATCH_PROTO(as->as.ai.hints.ai_protocol, i)) 704 continue; 705 706 proto = as->as.ai.hints.ai_protocol; 707 if (!proto) 708 proto = matches[i].protocol; 709 710 if (proto == IPPROTO_TCP) 711 port = as->as.ai.port_tcp; 712 else if (proto == IPPROTO_UDP) 713 port = as->as.ai.port_udp; 714 else 715 port = 0; 716 717 /* servname specified, but not defined for this protocol */ 718 if (port == -1) 719 continue; 720 721 ai = calloc(1, sizeof(*ai) + sa->sa_len); 722 if (ai == NULL) 723 return (EAI_MEMORY); 724 ai->ai_family = sa->sa_family; 725 ai->ai_socktype = matches[i].socktype; 726 ai->ai_protocol = proto; 727 ai->ai_flags = as->as.ai.hints.ai_flags; 728 ai->ai_addrlen = sa->sa_len; 729 ai->ai_addr = (void *)(ai + 1); 730 if (cname && 731 as->as.ai.hints.ai_flags & (AI_CANONNAME | AI_FQDN)) { 732 if ((ai->ai_canonname = strdup(cname)) == NULL) { 733 free(ai); 734 return (EAI_MEMORY); 735 } 736 } 737 memmove(ai->ai_addr, sa, sa->sa_len); 738 if (sa->sa_family == PF_INET) 739 ((struct sockaddr_in *)ai->ai_addr)->sin_port = 740 htons(port); 741 else if (sa->sa_family == PF_INET6) 742 ((struct sockaddr_in6 *)ai->ai_addr)->sin6_port = 743 htons(port); 744 745 if (as->as.ai.aifirst == NULL) 746 as->as.ai.aifirst = ai; 747 if (as->as.ai.ailast) 748 as->as.ai.ailast->ai_next = ai; 749 as->as.ai.ailast = ai; 750 as->as_count += 1; 751 } 752 753 return (0); 754 } 755 756 static int 757 addrinfo_from_file(struct asr_query *as, int family, FILE *f) 758 { 759 char *tokens[MAXTOKEN], *c; 760 int n, i; 761 union { 762 struct sockaddr sa; 763 struct sockaddr_in sain; 764 struct sockaddr_in6 sain6; 765 } u; 766 767 for (;;) { 768 n = asr_parse_namedb_line(f, tokens, MAXTOKEN); 769 if (n == -1) 770 break; /* ignore errors reading the file */ 771 772 for (i = 1; i < n; i++) { 773 if (strcasecmp(as->as.ai.hostname, tokens[i])) 774 continue; 775 if (asr_sockaddr_from_str(&u.sa, family, tokens[0]) == -1) 776 continue; 777 break; 778 } 779 if (i == n) 780 continue; 781 782 if (as->as.ai.hints.ai_flags & (AI_CANONNAME | AI_FQDN)) 783 c = tokens[1]; 784 else 785 c = NULL; 786 787 if (addrinfo_add(as, &u.sa, c)) 788 return (-1); /* errno set */ 789 } 790 return (0); 791 } 792 793 static int 794 addrinfo_from_pkt(struct asr_query *as, char *pkt, size_t pktlen) 795 { 796 struct asr_unpack p; 797 struct asr_dns_header h; 798 struct asr_dns_query q; 799 struct asr_dns_rr rr; 800 int i; 801 union { 802 struct sockaddr sa; 803 struct sockaddr_in sain; 804 struct sockaddr_in6 sain6; 805 } u; 806 char buf[MAXDNAME], *c; 807 808 asr_unpack_init(&p, pkt, pktlen); 809 asr_unpack_header(&p, &h); 810 for (; h.qdcount; h.qdcount--) 811 asr_unpack_query(&p, &q); 812 813 for (i = 0; i < h.ancount; i++) { 814 asr_unpack_rr(&p, &rr); 815 if (rr.rr_type != q.q_type || 816 rr.rr_class != q.q_class) 817 continue; 818 819 memset(&u, 0, sizeof u); 820 if (rr.rr_type == T_A) { 821 u.sain.sin_len = sizeof u.sain; 822 u.sain.sin_family = AF_INET; 823 u.sain.sin_addr = rr.rr.in_a.addr; 824 u.sain.sin_port = 0; 825 } else if (rr.rr_type == T_AAAA) { 826 u.sain6.sin6_len = sizeof u.sain6; 827 u.sain6.sin6_family = AF_INET6; 828 u.sain6.sin6_addr = rr.rr.in_aaaa.addr6; 829 u.sain6.sin6_port = 0; 830 } else 831 continue; 832 833 if (as->as.ai.hints.ai_flags & AI_CANONNAME) { 834 asr_strdname(rr.rr_dname, buf, sizeof buf); 835 buf[strlen(buf) - 1] = '\0'; 836 c = res_hnok(buf) ? buf : NULL; 837 } else if (as->as.ai.hints.ai_flags & AI_FQDN) 838 c = as->as.ai.fqdn; 839 else 840 c = NULL; 841 842 if (addrinfo_add(as, &u.sa, c)) 843 return (-1); /* errno set */ 844 } 845 return (0); 846 } 847 848 #ifdef YP 849 static int 850 strsplit(char *line, char **tokens, int ntokens) 851 { 852 int ntok; 853 char *cp, **tp; 854 855 for (cp = line, tp = tokens, ntok = 0; 856 ntok < ntokens && (*tp = strsep(&cp, " \t")) != NULL; ) 857 if (**tp != '\0') { 858 tp++; 859 ntok++; 860 } 861 862 return (ntok); 863 } 864 865 static int 866 addrinfo_from_yp(struct asr_query *as, int family, char *line) 867 { 868 char *next, *tokens[MAXTOKEN], *c; 869 int ntok; 870 union { 871 struct sockaddr sa; 872 struct sockaddr_in sain; 873 struct sockaddr_in6 sain6; 874 } u; 875 876 for (next = line; line; line = next) { 877 if ((next = strchr(line, '\n'))) { 878 *next = '\0'; 879 next += 1; 880 } 881 ntok = strsplit(line, tokens, MAXTOKEN); 882 if (ntok < 2) 883 continue; 884 885 if (asr_sockaddr_from_str(&u.sa, family, tokens[0]) == -1) 886 continue; 887 888 if (as->as.ai.hints.ai_flags & (AI_CANONNAME | AI_FQDN)) 889 c = tokens[1]; 890 else 891 c = NULL; 892 893 if (addrinfo_add(as, &u.sa, c)) 894 return (-1); /* errno set */ 895 } 896 return (0); 897 } 898 #endif 899