1 /* $OpenBSD: getaddrinfo_async.c,v 1.32 2015/01/14 23:36:15 deraadt 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, v4, v6; 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 v4 = 0; 217 v6 = 0; 218 for (ifa = ifa0; ifa != NULL; ifa = ifa->ifa_next) { 219 if (ifa->ifa_flags & IFF_LOOPBACK) 220 continue; 221 if (ifa->ifa_addr->sa_family == PF_INET) 222 v4 = 1; 223 else if (ifa->ifa_addr->sa_family == PF_INET6 && 224 !IN6_IS_ADDR_LINKLOCAL(&((struct 225 sockaddr_in6 *)ifa->ifa_addr)->sin6_addr)) 226 v6 = 1; 227 } 228 freeifaddrs(ifa0); 229 if ((ai->ai_family == PF_UNSPEC && !v4 && !v6) || 230 (ai->ai_family == PF_INET && !v4) || 231 (ai->ai_family == PF_INET6 && !v6)) { 232 ar->ar_gai_errno = EAI_NONAME; 233 async_set_state(as, ASR_STATE_HALT); 234 break; 235 } 236 if (ai->ai_family == PF_UNSPEC && v4 && !v6) 237 ai->ai_family = PF_INET; 238 if (ai->ai_family == PF_UNSPEC && !v4 && v6) 239 ai->ai_family = PF_INET6; 240 } 241 242 /* Make sure there is at least a valid combination */ 243 for (i = 0; matches[i].family != -1; i++) 244 if (MATCH_FAMILY(ai->ai_family, i) && 245 MATCH_SOCKTYPE(ai->ai_socktype, i) && 246 MATCH_PROTO(ai->ai_protocol, i)) 247 break; 248 if (matches[i].family == -1) { 249 ar->ar_gai_errno = EAI_BADHINTS; 250 async_set_state(as, ASR_STATE_HALT); 251 break; 252 } 253 254 if (ai->ai_protocol == 0 || ai->ai_protocol == IPPROTO_UDP) 255 as->as.ai.port_udp = get_port(as->as.ai.servname, "udp", 256 as->as.ai.hints.ai_flags & AI_NUMERICSERV); 257 if (ai->ai_protocol == 0 || ai->ai_protocol == IPPROTO_TCP) 258 as->as.ai.port_tcp = get_port(as->as.ai.servname, "tcp", 259 as->as.ai.hints.ai_flags & AI_NUMERICSERV); 260 if (as->as.ai.port_tcp == -2 || as->as.ai.port_udp == -2 || 261 (as->as.ai.port_tcp == -1 && as->as.ai.port_udp == -1) || 262 (ai->ai_protocol && (as->as.ai.port_udp == -1 || 263 as->as.ai.port_tcp == -1))) { 264 ar->ar_gai_errno = EAI_SERVICE; 265 async_set_state(as, ASR_STATE_HALT); 266 break; 267 } 268 269 ar->ar_gai_errno = 0; 270 271 /* If hostname is NULL, use local address */ 272 if (as->as.ai.hostname == NULL) { 273 for (family = iter_family(as, 1); 274 family != -1; 275 family = iter_family(as, 0)) { 276 /* 277 * We could use statically built sockaddrs for 278 * those, rather than parsing over and over. 279 */ 280 if (family == PF_INET) 281 str = (ai->ai_flags & AI_PASSIVE) ? \ 282 "0.0.0.0" : "127.0.0.1"; 283 else /* PF_INET6 */ 284 str = (ai->ai_flags & AI_PASSIVE) ? \ 285 "::" : "::1"; 286 /* This can't fail */ 287 asr_sockaddr_from_str(&sa.sa, family, str); 288 if ((r = addrinfo_add(as, &sa.sa, NULL))) { 289 ar->ar_gai_errno = r; 290 break; 291 } 292 } 293 if (ar->ar_gai_errno == 0 && as->as_count == 0) { 294 ar->ar_gai_errno = EAI_NODATA; 295 } 296 async_set_state(as, ASR_STATE_HALT); 297 break; 298 } 299 300 /* Try numeric addresses first */ 301 for (family = iter_family(as, 1); 302 family != -1; 303 family = iter_family(as, 0)) { 304 305 if (asr_sockaddr_from_str(&sa.sa, family, 306 as->as.ai.hostname) == -1) 307 continue; 308 309 if ((r = addrinfo_add(as, &sa.sa, NULL))) 310 ar->ar_gai_errno = r; 311 break; 312 } 313 if (ar->ar_gai_errno || as->as_count) { 314 async_set_state(as, ASR_STATE_HALT); 315 break; 316 } 317 318 if (ai->ai_flags & AI_NUMERICHOST) { 319 ar->ar_gai_errno = EAI_NONAME; 320 async_set_state(as, ASR_STATE_HALT); 321 break; 322 } 323 324 async_set_state(as, ASR_STATE_NEXT_DB); 325 break; 326 327 case ASR_STATE_NEXT_DB: 328 if (asr_iter_db(as) == -1) { 329 async_set_state(as, ASR_STATE_NOT_FOUND); 330 break; 331 } 332 as->as_family_idx = 0; 333 async_set_state(as, ASR_STATE_SAME_DB); 334 break; 335 336 case ASR_STATE_NEXT_FAMILY: 337 as->as_family_idx += 1; 338 if (as->as.ai.hints.ai_family != AF_UNSPEC || 339 AS_FAMILY(as) == -1) { 340 /* The family was specified, or we have tried all 341 * families with this DB. 342 */ 343 if (as->as_count) { 344 ar->ar_gai_errno = 0; 345 async_set_state(as, ASR_STATE_HALT); 346 } else 347 async_set_state(as, ASR_STATE_NEXT_DOMAIN); 348 break; 349 } 350 async_set_state(as, ASR_STATE_SAME_DB); 351 break; 352 353 case ASR_STATE_NEXT_DOMAIN: 354 /* domain search is only for dns */ 355 if (AS_DB(as) != ASR_DB_DNS) { 356 async_set_state(as, ASR_STATE_NEXT_DB); 357 break; 358 } 359 as->as_family_idx = 0; 360 361 free(as->as.ai.fqdn); 362 as->as.ai.fqdn = NULL; 363 r = iter_domain(as, as->as.ai.hostname, fqdn, sizeof(fqdn)); 364 if (r == -1) { 365 async_set_state(as, ASR_STATE_NEXT_DB); 366 break; 367 } 368 if (r == 0) { 369 ar->ar_gai_errno = EAI_FAIL; 370 async_set_state(as, ASR_STATE_HALT); 371 break; 372 } 373 as->as.ai.fqdn = strdup(fqdn); 374 if (as->as.ai.fqdn == NULL) { 375 ar->ar_gai_errno = EAI_MEMORY; 376 async_set_state(as, ASR_STATE_HALT); 377 } 378 379 async_set_state(as, ASR_STATE_SAME_DB); 380 break; 381 382 case ASR_STATE_SAME_DB: 383 /* query the current DB again */ 384 switch (AS_DB(as)) { 385 case ASR_DB_DNS: 386 if (as->as.ai.fqdn == NULL) { 387 /* First try, initialize domain iteration */ 388 as->as_dom_flags = 0; 389 as->as_dom_step = DOM_INIT; 390 async_set_state(as, ASR_STATE_NEXT_DOMAIN); 391 break; 392 } 393 394 family = (as->as.ai.hints.ai_family == AF_UNSPEC) ? 395 AS_FAMILY(as) : as->as.ai.hints.ai_family; 396 397 as->as.ai.subq = res_query_async_ctx(as->as.ai.fqdn, 398 C_IN, (family == AF_INET6) ? T_AAAA : T_A, 399 as->as_ctx); 400 401 if (as->as.ai.subq == NULL) { 402 if (errno == ENOMEM) 403 ar->ar_gai_errno = EAI_MEMORY; 404 else 405 ar->ar_gai_errno = EAI_FAIL; 406 async_set_state(as, ASR_STATE_HALT); 407 break; 408 } 409 async_set_state(as, ASR_STATE_SUBQUERY); 410 break; 411 412 case ASR_DB_FILE: 413 f = fopen(as->as_ctx->ac_hostfile, "re"); 414 if (f == NULL) { 415 async_set_state(as, ASR_STATE_NEXT_DB); 416 break; 417 } 418 family = (as->as.ai.hints.ai_family == AF_UNSPEC) ? 419 AS_FAMILY(as) : as->as.ai.hints.ai_family; 420 421 r = addrinfo_from_file(as, family, f); 422 if (r == -1) { 423 if (errno == ENOMEM) 424 ar->ar_gai_errno = EAI_MEMORY; 425 else 426 ar->ar_gai_errno = EAI_FAIL; 427 async_set_state(as, ASR_STATE_HALT); 428 } else 429 async_set_state(as, ASR_STATE_NEXT_FAMILY); 430 fclose(f); 431 break; 432 433 #ifdef YP 434 case ASR_DB_YP: 435 if (!domain && _yp_check(&domain) == 0) { 436 async_set_state(as, ASR_STATE_NEXT_DB); 437 break; 438 } 439 family = (as->as.ai.hints.ai_family == AF_UNSPEC) ? 440 AS_FAMILY(as) : as->as.ai.hints.ai_family; 441 442 name = as->as.ai.hostname; 443 444 /* XXX 445 * ipnodes.byname could also contain IPv4 address 446 */ 447 r = yp_match(domain, (family == AF_INET6) ? 448 "ipnodes.byname" : "hosts.byname", 449 name, strlen(name), &res, &len); 450 if (r == 0) { 451 r = addrinfo_from_yp(as, family, res); 452 free(res); 453 if (r == -1) { 454 if (errno == ENOMEM) 455 ar->ar_gai_errno = EAI_MEMORY; 456 else 457 ar->ar_gai_errno = EAI_FAIL; 458 async_set_state(as, ASR_STATE_HALT); 459 break; 460 } 461 } 462 async_set_state(as, ASR_STATE_NEXT_FAMILY); 463 break; 464 #endif 465 default: 466 async_set_state(as, ASR_STATE_NEXT_DB); 467 } 468 break; 469 470 case ASR_STATE_SUBQUERY: 471 if ((r = asr_run(as->as.ai.subq, ar)) == ASYNC_COND) 472 return (ASYNC_COND); 473 474 as->as.ai.subq = NULL; 475 476 if (ar->ar_datalen == -1) { 477 async_set_state(as, ASR_STATE_NEXT_FAMILY); 478 break; 479 } 480 481 r = addrinfo_from_pkt(as, ar->ar_data, ar->ar_datalen); 482 if (r == -1) { 483 if (errno == ENOMEM) 484 ar->ar_gai_errno = EAI_MEMORY; 485 else 486 ar->ar_gai_errno = EAI_FAIL; 487 async_set_state(as, ASR_STATE_HALT); 488 } else 489 async_set_state(as, ASR_STATE_NEXT_FAMILY); 490 free(ar->ar_data); 491 break; 492 493 case ASR_STATE_NOT_FOUND: 494 /* No result found. Maybe we can try again. */ 495 if (as->as.ai.flags & ASYNC_AGAIN) 496 ar->ar_gai_errno = EAI_AGAIN; 497 else 498 ar->ar_gai_errno = EAI_NODATA; 499 async_set_state(as, ASR_STATE_HALT); 500 break; 501 502 case ASR_STATE_HALT: 503 if (ar->ar_gai_errno == 0) { 504 ar->ar_count = as->as_count; 505 ar->ar_addrinfo = as->as.ai.aifirst; 506 as->as.ai.aifirst = NULL; 507 } else { 508 ar->ar_count = 0; 509 ar->ar_addrinfo = NULL; 510 } 511 return (ASYNC_DONE); 512 513 default: 514 ar->ar_errno = EOPNOTSUPP; 515 ar->ar_gai_errno = EAI_SYSTEM; 516 async_set_state(as, ASR_STATE_HALT); 517 break; 518 } 519 goto next; 520 } 521 522 /* 523 * Retreive the port number for the service name "servname" and 524 * the protocol "proto". 525 */ 526 static int 527 get_port(const char *servname, const char *proto, int numonly) 528 { 529 struct servent se; 530 struct servent_data sed; 531 int port, r; 532 const char *e; 533 534 if (servname == NULL) 535 return (0); 536 537 e = NULL; 538 port = strtonum(servname, 0, USHRT_MAX, &e); 539 if (e == NULL) 540 return (port); 541 if (errno == ERANGE) 542 return (-2); /* invalid */ 543 if (numonly) 544 return (-2); 545 546 memset(&sed, 0, sizeof(sed)); 547 r = getservbyname_r(servname, proto, &se, &sed); 548 port = ntohs(se.s_port); 549 endservent_r(&sed); 550 551 if (r == -1) 552 return (-1); /* not found */ 553 554 return (port); 555 } 556 557 /* 558 * Iterate over the address families that are to be queried. Use the 559 * list on the async context, unless a specific family was given in hints. 560 */ 561 static int 562 iter_family(struct asr_query *as, int first) 563 { 564 if (first) { 565 as->as_family_idx = 0; 566 if (as->as.ai.hints.ai_family != PF_UNSPEC) 567 return as->as.ai.hints.ai_family; 568 return AS_FAMILY(as); 569 } 570 571 if (as->as.ai.hints.ai_family != PF_UNSPEC) 572 return (-1); 573 574 as->as_family_idx++; 575 576 return AS_FAMILY(as); 577 } 578 579 /* 580 * Concatenate a name and a domain name. The result has no trailing dot. 581 * Return the resulting string length, or 0 in case of error. 582 */ 583 static size_t 584 domcat(const char *name, const char *domain, char *buf, size_t buflen) 585 { 586 size_t r; 587 588 r = asr_make_fqdn(name, domain, buf, buflen); 589 if (r == 0) 590 return (0); 591 buf[r - 1] = '\0'; 592 593 return (r - 1); 594 } 595 596 /* 597 * Implement the search domain strategy. 598 * 599 * XXX duplicate from res_search_async 600 * 601 * This function works as a generator that constructs complete domains in 602 * buffer "buf" of size "len" for the given host name "name", according to the 603 * search rules defined by the resolving context. It is supposed to be called 604 * multiple times (with the same name) to generate the next possible domain 605 * name, if any. 606 * 607 * It returns -1 if all possibilities have been exhausted, 0 if there was an 608 * error generating the next name, or the resulting name length. 609 */ 610 static int 611 iter_domain(struct asr_query *as, const char *name, char * buf, size_t len) 612 { 613 const char *c; 614 int dots; 615 616 switch (as->as_dom_step) { 617 618 case DOM_INIT: 619 /* First call */ 620 621 /* 622 * If "name" is an FQDN, that's the only result and we 623 * don't try anything else. 624 */ 625 if (strlen(name) && name[strlen(name) - 1] == '.') { 626 DPRINT("asr: iter_domain(\"%s\") fqdn\n", name); 627 as->as_dom_flags |= ASYNC_DOM_FQDN; 628 as->as_dom_step = DOM_DONE; 629 return (domcat(name, NULL, buf, len)); 630 } 631 632 /* 633 * Otherwise, we iterate through the specified search domains. 634 */ 635 as->as_dom_step = DOM_DOMAIN; 636 as->as_dom_idx = 0; 637 638 /* 639 * If "name" as enough dots, use it as-is first, as indicated 640 * in resolv.conf(5). 641 */ 642 dots = 0; 643 for (c = name; *c; c++) 644 dots += (*c == '.'); 645 if (dots >= as->as_ctx->ac_ndots) { 646 DPRINT("asr: iter_domain(\"%s\") ndots\n", name); 647 as->as_dom_flags |= ASYNC_DOM_NDOTS; 648 if (strlcpy(buf, name, len) >= len) 649 return (0); 650 return (strlen(buf)); 651 } 652 /* Otherwise, starts using the search domains */ 653 /* FALLTHROUGH */ 654 655 case DOM_DOMAIN: 656 if (as->as_dom_idx < as->as_ctx->ac_domcount) { 657 DPRINT("asr: iter_domain(\"%s\") domain \"%s\"\n", 658 name, as->as_ctx->ac_dom[as->as_dom_idx]); 659 as->as_dom_flags |= ASYNC_DOM_DOMAIN; 660 return (domcat(name, 661 as->as_ctx->ac_dom[as->as_dom_idx++], buf, len)); 662 } 663 664 /* No more domain to try. */ 665 666 as->as_dom_step = DOM_DONE; 667 668 /* 669 * If the name was not tried as an absolute name before, 670 * do it now. 671 */ 672 if (!(as->as_dom_flags & ASYNC_DOM_NDOTS)) { 673 DPRINT("asr: iter_domain(\"%s\") as is\n", name); 674 as->as_dom_flags |= ASYNC_DOM_ASIS; 675 if (strlcpy(buf, name, len) >= len) 676 return (0); 677 return (strlen(buf)); 678 } 679 /* Otherwise, we are done. */ 680 681 case DOM_DONE: 682 default: 683 DPRINT("asr: iter_domain(\"%s\") done\n", name); 684 return (-1); 685 } 686 } 687 688 /* 689 * Use the sockaddr at "sa" to extend the result list on the "as" context, 690 * with the specified canonical name "cname". This function adds one 691 * entry per protocol/socktype match. 692 */ 693 static int 694 addrinfo_add(struct asr_query *as, const struct sockaddr *sa, const char *cname) 695 { 696 struct addrinfo *ai; 697 int i, port, proto; 698 699 for (i = 0; matches[i].family != -1; i++) { 700 if (matches[i].family != sa->sa_family || 701 !MATCH_SOCKTYPE(as->as.ai.hints.ai_socktype, i) || 702 !MATCH_PROTO(as->as.ai.hints.ai_protocol, i)) 703 continue; 704 705 proto = as->as.ai.hints.ai_protocol; 706 if (!proto) 707 proto = matches[i].protocol; 708 709 if (proto == IPPROTO_TCP) 710 port = as->as.ai.port_tcp; 711 else if (proto == IPPROTO_UDP) 712 port = as->as.ai.port_udp; 713 else 714 port = 0; 715 716 /* servname specified, but not defined for this protocol */ 717 if (port == -1) 718 continue; 719 720 ai = calloc(1, sizeof(*ai) + sa->sa_len); 721 if (ai == NULL) 722 return (EAI_MEMORY); 723 ai->ai_family = sa->sa_family; 724 ai->ai_socktype = matches[i].socktype; 725 ai->ai_protocol = proto; 726 ai->ai_flags = as->as.ai.hints.ai_flags; 727 ai->ai_addrlen = sa->sa_len; 728 ai->ai_addr = (void *)(ai + 1); 729 if (cname && 730 as->as.ai.hints.ai_flags & (AI_CANONNAME | AI_FQDN)) { 731 if ((ai->ai_canonname = strdup(cname)) == NULL) { 732 free(ai); 733 return (EAI_MEMORY); 734 } 735 } 736 memmove(ai->ai_addr, sa, sa->sa_len); 737 if (sa->sa_family == PF_INET) 738 ((struct sockaddr_in *)ai->ai_addr)->sin_port = 739 htons(port); 740 else if (sa->sa_family == PF_INET6) 741 ((struct sockaddr_in6 *)ai->ai_addr)->sin6_port = 742 htons(port); 743 744 if (as->as.ai.aifirst == NULL) 745 as->as.ai.aifirst = ai; 746 if (as->as.ai.ailast) 747 as->as.ai.ailast->ai_next = ai; 748 as->as.ai.ailast = ai; 749 as->as_count += 1; 750 } 751 752 return (0); 753 } 754 755 static int 756 addrinfo_from_file(struct asr_query *as, int family, FILE *f) 757 { 758 char *tokens[MAXTOKEN], *c; 759 int n, i; 760 union { 761 struct sockaddr sa; 762 struct sockaddr_in sain; 763 struct sockaddr_in6 sain6; 764 } u; 765 766 for (;;) { 767 n = asr_parse_namedb_line(f, tokens, MAXTOKEN); 768 if (n == -1) 769 break; /* ignore errors reading the file */ 770 771 for (i = 1; i < n; i++) { 772 if (strcasecmp(as->as.ai.hostname, tokens[i])) 773 continue; 774 if (asr_sockaddr_from_str(&u.sa, family, tokens[0]) == -1) 775 continue; 776 break; 777 } 778 if (i == n) 779 continue; 780 781 if (as->as.ai.hints.ai_flags & (AI_CANONNAME | AI_FQDN)) 782 c = tokens[1]; 783 else 784 c = NULL; 785 786 if (addrinfo_add(as, &u.sa, c)) 787 return (-1); /* errno set */ 788 } 789 return (0); 790 } 791 792 static int 793 addrinfo_from_pkt(struct asr_query *as, char *pkt, size_t pktlen) 794 { 795 struct asr_unpack p; 796 struct asr_dns_header h; 797 struct asr_dns_query q; 798 struct asr_dns_rr rr; 799 int i; 800 union { 801 struct sockaddr sa; 802 struct sockaddr_in sain; 803 struct sockaddr_in6 sain6; 804 } u; 805 char buf[MAXDNAME], *c; 806 807 asr_unpack_init(&p, pkt, pktlen); 808 asr_unpack_header(&p, &h); 809 for (; h.qdcount; h.qdcount--) 810 asr_unpack_query(&p, &q); 811 812 for (i = 0; i < h.ancount; i++) { 813 asr_unpack_rr(&p, &rr); 814 if (rr.rr_type != q.q_type || 815 rr.rr_class != q.q_class) 816 continue; 817 818 memset(&u, 0, sizeof u); 819 if (rr.rr_type == T_A) { 820 u.sain.sin_len = sizeof u.sain; 821 u.sain.sin_family = AF_INET; 822 u.sain.sin_addr = rr.rr.in_a.addr; 823 u.sain.sin_port = 0; 824 } else if (rr.rr_type == T_AAAA) { 825 u.sain6.sin6_len = sizeof u.sain6; 826 u.sain6.sin6_family = AF_INET6; 827 u.sain6.sin6_addr = rr.rr.in_aaaa.addr6; 828 u.sain6.sin6_port = 0; 829 } else 830 continue; 831 832 if (as->as.ai.hints.ai_flags & AI_CANONNAME) { 833 asr_strdname(rr.rr_dname, buf, sizeof buf); 834 buf[strlen(buf) - 1] = '\0'; 835 c = res_hnok(buf) ? buf : NULL; 836 } else if (as->as.ai.hints.ai_flags & AI_FQDN) 837 c = as->as.ai.fqdn; 838 else 839 c = NULL; 840 841 if (addrinfo_add(as, &u.sa, c)) 842 return (-1); /* errno set */ 843 } 844 return (0); 845 } 846 847 #ifdef YP 848 static int 849 strsplit(char *line, char **tokens, int ntokens) 850 { 851 int ntok; 852 char *cp, **tp; 853 854 for (cp = line, tp = tokens, ntok = 0; 855 ntok < ntokens && (*tp = strsep(&cp, " \t")) != NULL; ) 856 if (**tp != '\0') { 857 tp++; 858 ntok++; 859 } 860 861 return (ntok); 862 } 863 864 static int 865 addrinfo_from_yp(struct asr_query *as, int family, char *line) 866 { 867 char *next, *tokens[MAXTOKEN], *c; 868 int ntok; 869 union { 870 struct sockaddr sa; 871 struct sockaddr_in sain; 872 struct sockaddr_in6 sain6; 873 } u; 874 875 for (next = line; line; line = next) { 876 if ((next = strchr(line, '\n'))) { 877 *next = '\0'; 878 next += 1; 879 } 880 ntok = strsplit(line, tokens, MAXTOKEN); 881 if (ntok < 2) 882 continue; 883 884 if (asr_sockaddr_from_str(&u.sa, family, tokens[0]) == -1) 885 continue; 886 887 if (as->as.ai.hints.ai_flags & (AI_CANONNAME | AI_FQDN)) 888 c = tokens[1]; 889 else 890 c = NULL; 891 892 if (addrinfo_add(as, &u.sa, c)) 893 return (-1); /* errno set */ 894 } 895 return (0); 896 } 897 #endif 898