1 /* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * Issues to be discussed: 34 * - Return values. There are nonstandard return values defined and used 35 * in the source code. This is because RFC2553 is silent about which error 36 * code must be returned for which situation. 37 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 38 * invalid. current code - SEGV on freeaddrinfo(NULL) 39 * 40 * Note: 41 * - The code filters out AFs that are not supported by the kernel, 42 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 43 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 44 * in ai_flags? 45 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 46 * (1) what should we do against numeric hostname (2) what should we do 47 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 48 * non-loopback address configured? global address configured? 49 * 50 * OS specific notes for freebsd4: 51 * - FreeBSD supported $GAI. The code does not. 52 */ 53 54 #include <sys/cdefs.h> 55 __FBSDID("$FreeBSD$"); 56 57 #include "namespace.h" 58 #include <sys/types.h> 59 #include <sys/param.h> 60 #include <sys/socket.h> 61 #include <net/if.h> 62 #include <netinet/in.h> 63 #include <net/if_types.h> 64 #include <ifaddrs.h> 65 #include <sys/queue.h> 66 #ifdef INET6 67 #include <sys/sysctl.h> 68 #include <sys/ioctl.h> 69 #include <netinet6/in6_var.h> 70 #include <netinet6/nd6.h> 71 #endif 72 #include <arpa/inet.h> 73 #include <arpa/nameser.h> 74 #include <rpc/rpc.h> 75 #include <rpcsvc/yp_prot.h> 76 #include <rpcsvc/ypclnt.h> 77 #include <netdb.h> 78 #include <resolv.h> 79 #include <string.h> 80 #include <stdlib.h> 81 #include <stddef.h> 82 #include <ctype.h> 83 #include <unistd.h> 84 #include <stdio.h> 85 #include <errno.h> 86 87 #include "res_config.h" 88 89 #ifdef DEBUG 90 #include <syslog.h> 91 #endif 92 93 #include <stdarg.h> 94 #include <nsswitch.h> 95 #include "un-namespace.h" 96 #include "libc_private.h" 97 #ifdef NS_CACHING 98 #include "nscache.h" 99 #endif 100 101 #define ANY 0 102 #define YES 1 103 #define NO 0 104 105 static const char in_addrany[] = { 0, 0, 0, 0 }; 106 static const char in_loopback[] = { 127, 0, 0, 1 }; 107 #ifdef INET6 108 static const char in6_addrany[] = { 109 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 110 }; 111 static const char in6_loopback[] = { 112 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 113 }; 114 #endif 115 116 struct policyqueue { 117 TAILQ_ENTRY(policyqueue) pc_entry; 118 #ifdef INET6 119 struct in6_addrpolicy pc_policy; 120 #endif 121 }; 122 TAILQ_HEAD(policyhead, policyqueue); 123 124 static const struct afd { 125 int a_af; 126 int a_addrlen; 127 socklen_t a_socklen; 128 int a_off; 129 const char *a_addrany; 130 const char *a_loopback; 131 int a_scoped; 132 } afdl [] = { 133 #ifdef INET6 134 #define N_INET6 0 135 {PF_INET6, sizeof(struct in6_addr), 136 sizeof(struct sockaddr_in6), 137 offsetof(struct sockaddr_in6, sin6_addr), 138 in6_addrany, in6_loopback, 1}, 139 #define N_INET 1 140 #else 141 #define N_INET 0 142 #endif 143 {PF_INET, sizeof(struct in_addr), 144 sizeof(struct sockaddr_in), 145 offsetof(struct sockaddr_in, sin_addr), 146 in_addrany, in_loopback, 0}, 147 {0, 0, 0, 0, NULL, NULL, 0}, 148 }; 149 150 struct explore { 151 int e_af; 152 int e_socktype; 153 int e_protocol; 154 int e_wild; 155 #define WILD_AF(ex) ((ex)->e_wild & 0x01) 156 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 157 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 158 }; 159 160 static const struct explore explore[] = { 161 #if 0 162 { PF_LOCAL, ANY, ANY, 0x01 }, 163 #endif 164 #ifdef INET6 165 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, 0x07 }, 166 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, 0x07 }, 167 { PF_INET6, SOCK_STREAM, IPPROTO_SCTP, 0x03 }, 168 { PF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 }, 169 { PF_INET6, SOCK_DGRAM, IPPROTO_UDPLITE, 0x03 }, 170 { PF_INET6, SOCK_RAW, ANY, 0x05 }, 171 #endif 172 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, 0x07 }, 173 { PF_INET, SOCK_STREAM, IPPROTO_TCP, 0x07 }, 174 { PF_INET, SOCK_STREAM, IPPROTO_SCTP, 0x03 }, 175 { PF_INET, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 }, 176 { PF_INET, SOCK_DGRAM, IPPROTO_UDPLITE, 0x03 }, 177 { PF_INET, SOCK_RAW, ANY, 0x05 }, 178 { -1, 0, 0, 0 }, 179 }; 180 181 #ifdef INET6 182 #define PTON_MAX 16 183 #else 184 #define PTON_MAX 4 185 #endif 186 187 #define AIO_SRCFLAG_DEPRECATED 0x1 188 189 struct ai_order { 190 union { 191 struct sockaddr_storage aiou_ss; 192 struct sockaddr aiou_sa; 193 } aio_src_un; 194 #define aio_srcsa aio_src_un.aiou_sa 195 u_int32_t aio_srcflag; 196 int aio_srcscope; 197 int aio_dstscope; 198 struct policyqueue *aio_srcpolicy; 199 struct policyqueue *aio_dstpolicy; 200 struct addrinfo *aio_ai; 201 int aio_matchlen; 202 }; 203 204 static const ns_src default_dns_files[] = { 205 { NSSRC_FILES, NS_SUCCESS }, 206 { NSSRC_DNS, NS_SUCCESS }, 207 { 0 } 208 }; 209 210 struct res_target { 211 struct res_target *next; 212 const char *name; /* domain name */ 213 int qclass, qtype; /* class and type of query */ 214 u_char *answer; /* buffer to put answer */ 215 int anslen; /* size of answer buffer */ 216 int n; /* result length */ 217 }; 218 219 #define MAXPACKET (64*1024) 220 221 typedef union { 222 HEADER hdr; 223 u_char buf[MAXPACKET]; 224 } querybuf; 225 226 static int str2number(const char *, int *); 227 static int explore_copy(const struct addrinfo *, const struct addrinfo *, 228 struct addrinfo **); 229 static int explore_null(const struct addrinfo *, 230 const char *, struct addrinfo **); 231 static int explore_numeric(const struct addrinfo *, const char *, 232 const char *, struct addrinfo **, const char *); 233 static int explore_numeric_scope(const struct addrinfo *, const char *, 234 const char *, struct addrinfo **); 235 static int get_canonname(const struct addrinfo *, 236 struct addrinfo *, const char *); 237 static struct addrinfo *get_ai(const struct addrinfo *, 238 const struct afd *, const char *); 239 static struct addrinfo *copy_ai(const struct addrinfo *); 240 static int get_portmatch(const struct addrinfo *, const char *); 241 static int get_port(struct addrinfo *, const char *, int); 242 static const struct afd *find_afd(int); 243 static int addrconfig(struct addrinfo *); 244 #ifdef INET6 245 static int is_ifdisabled(char *); 246 #endif 247 static void set_source(struct ai_order *, struct policyhead *); 248 static int comp_dst(const void *, const void *); 249 #ifdef INET6 250 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 251 #endif 252 static int gai_addr2scopetype(struct sockaddr *); 253 254 static int explore_fqdn(const struct addrinfo *, const char *, 255 const char *, struct addrinfo **); 256 257 static int reorder(struct addrinfo *); 258 static int get_addrselectpolicy(struct policyhead *); 259 static void free_addrselectpolicy(struct policyhead *); 260 static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 261 struct policyhead *); 262 static int matchlen(struct sockaddr *, struct sockaddr *); 263 264 static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 265 const struct addrinfo *, res_state); 266 #if defined(RESOLVSORT) 267 static int addr4sort(struct addrinfo *, res_state); 268 #endif 269 static int _dns_getaddrinfo(void *, void *, va_list); 270 static void _sethtent(FILE **); 271 static void _endhtent(FILE **); 272 static struct addrinfo *_gethtent(FILE **, const char *, 273 const struct addrinfo *); 274 static int _files_getaddrinfo(void *, void *, va_list); 275 #ifdef YP 276 static struct addrinfo *_yphostent(char *, const struct addrinfo *); 277 static int _yp_getaddrinfo(void *, void *, va_list); 278 #endif 279 #ifdef NS_CACHING 280 static int addrinfo_id_func(char *, size_t *, va_list, void *); 281 static int addrinfo_marshal_func(char *, size_t *, void *, va_list, void *); 282 static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, void *); 283 #endif 284 285 static int res_queryN(const char *, struct res_target *, res_state); 286 static int res_searchN(const char *, struct res_target *, res_state); 287 static int res_querydomainN(const char *, const char *, 288 struct res_target *, res_state); 289 290 /* XXX macros that make external reference is BAD. */ 291 292 #define GET_AI(ai, afd, addr) \ 293 do { \ 294 /* external reference: pai, error, and label free */ \ 295 (ai) = get_ai(pai, (afd), (addr)); \ 296 if ((ai) == NULL) { \ 297 error = EAI_MEMORY; \ 298 goto free; \ 299 } \ 300 } while (/*CONSTCOND*/0) 301 302 #define GET_PORT(ai, serv) \ 303 do { \ 304 /* external reference: error and label free */ \ 305 error = get_port((ai), (serv), 0); \ 306 if (error != 0) \ 307 goto free; \ 308 } while (/*CONSTCOND*/0) 309 310 #define GET_CANONNAME(ai, str) \ 311 do { \ 312 /* external reference: pai, error and label free */ \ 313 error = get_canonname(pai, (ai), (str)); \ 314 if (error != 0) \ 315 goto free; \ 316 } while (/*CONSTCOND*/0) 317 318 #define ERR(err) \ 319 do { \ 320 /* external reference: error, and label bad */ \ 321 error = (err); \ 322 goto bad; \ 323 /*NOTREACHED*/ \ 324 } while (/*CONSTCOND*/0) 325 326 #define MATCH_FAMILY(x, y, w) \ 327 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 328 #define MATCH(x, y, w) \ 329 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 330 331 void 332 freeaddrinfo(struct addrinfo *ai) 333 { 334 struct addrinfo *next; 335 336 do { 337 next = ai->ai_next; 338 if (ai->ai_canonname) 339 free(ai->ai_canonname); 340 /* no need to free(ai->ai_addr) */ 341 free(ai); 342 ai = next; 343 } while (ai); 344 } 345 346 static int 347 str2number(const char *p, int *portp) 348 { 349 char *ep; 350 unsigned long v; 351 352 if (*p == '\0') 353 return -1; 354 ep = NULL; 355 errno = 0; 356 v = strtoul(p, &ep, 10); 357 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) { 358 *portp = v; 359 return 0; 360 } else 361 return -1; 362 } 363 364 int 365 getaddrinfo(const char *hostname, const char *servname, 366 const struct addrinfo *hints, struct addrinfo **res) 367 { 368 struct addrinfo sentinel; 369 struct addrinfo *cur; 370 int error = 0; 371 struct addrinfo ai, ai0, *afai; 372 struct addrinfo *pai; 373 const struct afd *afd; 374 const struct explore *ex; 375 struct addrinfo *afailist[sizeof(afdl)/sizeof(afdl[0])]; 376 struct addrinfo *afai_unspec; 377 int found; 378 int numeric = 0; 379 380 /* ensure we return NULL on errors */ 381 *res = NULL; 382 383 memset(&ai, 0, sizeof(ai)); 384 385 memset(afailist, 0, sizeof(afailist)); 386 afai_unspec = NULL; 387 388 memset(&sentinel, 0, sizeof(sentinel)); 389 cur = &sentinel; 390 pai = &ai; 391 pai->ai_flags = 0; 392 pai->ai_family = PF_UNSPEC; 393 pai->ai_socktype = ANY; 394 pai->ai_protocol = ANY; 395 pai->ai_addrlen = 0; 396 pai->ai_canonname = NULL; 397 pai->ai_addr = NULL; 398 pai->ai_next = NULL; 399 400 if (hostname == NULL && servname == NULL) 401 return EAI_NONAME; 402 if (hints) { 403 /* error check for hints */ 404 if (hints->ai_addrlen || hints->ai_canonname || 405 hints->ai_addr || hints->ai_next) 406 ERR(EAI_BADHINTS); /* xxx */ 407 if (hints->ai_flags & ~AI_MASK) 408 ERR(EAI_BADFLAGS); 409 switch (hints->ai_family) { 410 case PF_UNSPEC: 411 case PF_INET: 412 #ifdef INET6 413 case PF_INET6: 414 #endif 415 break; 416 default: 417 ERR(EAI_FAMILY); 418 } 419 memcpy(pai, hints, sizeof(*pai)); 420 421 /* 422 * if both socktype/protocol are specified, check if they 423 * are meaningful combination. 424 */ 425 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 426 for (ex = explore; ex->e_af >= 0; ex++) { 427 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, 428 WILD_AF(ex))) 429 continue; 430 if (!MATCH(pai->ai_socktype, ex->e_socktype, 431 WILD_SOCKTYPE(ex))) 432 continue; 433 if (!MATCH(pai->ai_protocol, ex->e_protocol, 434 WILD_PROTOCOL(ex))) 435 continue; 436 437 /* matched */ 438 break; 439 } 440 441 if (ex->e_af < 0) 442 ERR(EAI_BADHINTS); 443 } 444 } 445 446 /* 447 * check for special cases. (1) numeric servname is disallowed if 448 * socktype/protocol are left unspecified. (2) servname is disallowed 449 * for raw and other inet{,6} sockets. 450 */ 451 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 452 #ifdef PF_INET6 453 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 454 #endif 455 ) { 456 ai0 = *pai; /* backup *pai */ 457 458 if (pai->ai_family == PF_UNSPEC) { 459 #ifdef PF_INET6 460 pai->ai_family = PF_INET6; 461 #else 462 pai->ai_family = PF_INET; 463 #endif 464 } 465 error = get_portmatch(pai, servname); 466 if (error) 467 goto bad; 468 469 *pai = ai0; 470 } 471 472 ai0 = *pai; 473 474 /* 475 * NULL hostname, or numeric hostname. 476 * If numeric representation of AF1 can be interpreted as FQDN 477 * representation of AF2, we need to think again about the code below. 478 */ 479 found = 0; 480 for (afd = afdl; afd->a_af; afd++) { 481 *pai = ai0; 482 483 if (!MATCH_FAMILY(pai->ai_family, afd->a_af, 1)) 484 continue; 485 486 if (pai->ai_family == PF_UNSPEC) 487 pai->ai_family = afd->a_af; 488 489 if (hostname == NULL) { 490 error = explore_null(pai, servname, 491 &afailist[afd - afdl]); 492 493 /* 494 * Errors from explore_null should be unexpected and 495 * be caught to avoid returning an incomplete result. 496 */ 497 if (error != 0) 498 goto bad; 499 } else { 500 error = explore_numeric_scope(pai, hostname, servname, 501 &afailist[afd - afdl]); 502 503 /* 504 * explore_numeric_scope returns an error for address 505 * families that do not match that of hostname. 506 * Thus we should not catch the error at this moment. 507 */ 508 } 509 510 if (!error && afailist[afd - afdl]) 511 found++; 512 } 513 if (found) { 514 numeric = 1; 515 goto globcopy; 516 } 517 518 if (hostname == NULL) 519 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 520 if (pai->ai_flags & AI_NUMERICHOST) 521 ERR(EAI_NONAME); 522 523 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 524 ERR(EAI_FAIL); 525 526 /* 527 * hostname as alphabetical name. 528 */ 529 *pai = ai0; 530 error = explore_fqdn(pai, hostname, servname, &afai_unspec); 531 532 globcopy: 533 for (ex = explore; ex->e_af >= 0; ex++) { 534 *pai = ai0; 535 536 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 537 continue; 538 if (!MATCH(pai->ai_socktype, ex->e_socktype, 539 WILD_SOCKTYPE(ex))) 540 continue; 541 if (!MATCH(pai->ai_protocol, ex->e_protocol, 542 WILD_PROTOCOL(ex))) 543 continue; 544 545 if (pai->ai_family == PF_UNSPEC) 546 pai->ai_family = ex->e_af; 547 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 548 pai->ai_socktype = ex->e_socktype; 549 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 550 pai->ai_protocol = ex->e_protocol; 551 552 /* 553 * if the servname does not match socktype/protocol, ignore it. 554 */ 555 if (get_portmatch(pai, servname) != 0) 556 continue; 557 558 if (afai_unspec) 559 afai = afai_unspec; 560 else { 561 if ((afd = find_afd(pai->ai_family)) == NULL) 562 continue; 563 /* XXX assumes that afd points inside afdl[] */ 564 afai = afailist[afd - afdl]; 565 } 566 if (!afai) 567 continue; 568 569 error = explore_copy(pai, afai, &cur->ai_next); 570 if (error != 0) 571 goto bad; 572 573 while (cur && cur->ai_next) 574 cur = cur->ai_next; 575 } 576 577 /* 578 * ensure we return either: 579 * - error == 0, non-NULL *res 580 * - error != 0, NULL *res 581 */ 582 if (error == 0) { 583 if (sentinel.ai_next) { 584 /* 585 * If the returned entry is for an active connection, 586 * and the given name is not numeric, reorder the 587 * list, so that the application would try the list 588 * in the most efficient order. Since the head entry 589 * of the original list may contain ai_canonname and 590 * that entry may be moved elsewhere in the new list, 591 * we keep the pointer and will restore it in the new 592 * head entry. (Note that RFC3493 requires the head 593 * entry store it when requested by the caller). 594 */ 595 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 596 if (!numeric) { 597 char *canonname; 598 599 canonname = 600 sentinel.ai_next->ai_canonname; 601 sentinel.ai_next->ai_canonname = NULL; 602 (void)reorder(&sentinel); 603 if (sentinel.ai_next->ai_canonname == 604 NULL) { 605 sentinel.ai_next->ai_canonname 606 = canonname; 607 } else if (canonname != NULL) 608 free(canonname); 609 } 610 } 611 *res = sentinel.ai_next; 612 } else 613 error = EAI_FAIL; 614 } 615 616 bad: 617 if (afai_unspec) 618 freeaddrinfo(afai_unspec); 619 for (afd = afdl; afd->a_af; afd++) { 620 if (afailist[afd - afdl]) 621 freeaddrinfo(afailist[afd - afdl]); 622 } 623 if (!*res) 624 if (sentinel.ai_next) 625 freeaddrinfo(sentinel.ai_next); 626 627 return (error); 628 } 629 630 static int 631 reorder(struct addrinfo *sentinel) 632 { 633 struct addrinfo *ai, **aip; 634 struct ai_order *aio; 635 int i, n; 636 struct policyhead policyhead; 637 638 /* count the number of addrinfo elements for sorting. */ 639 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 640 ; 641 642 /* 643 * If the number is small enough, we can skip the reordering process. 644 */ 645 if (n <= 1) 646 return(n); 647 648 /* allocate a temporary array for sort and initialization of it. */ 649 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 650 return(n); /* give up reordering */ 651 memset(aio, 0, sizeof(*aio) * n); 652 653 /* retrieve address selection policy from the kernel */ 654 TAILQ_INIT(&policyhead); 655 if (!get_addrselectpolicy(&policyhead)) { 656 /* no policy is installed into kernel, we don't sort. */ 657 free(aio); 658 return (n); 659 } 660 661 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 662 aio[i].aio_ai = ai; 663 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 664 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 665 &policyhead); 666 set_source(&aio[i], &policyhead); 667 } 668 669 /* perform sorting. */ 670 qsort(aio, n, sizeof(*aio), comp_dst); 671 672 /* reorder the addrinfo chain. */ 673 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 674 *aip = aio[i].aio_ai; 675 aip = &aio[i].aio_ai->ai_next; 676 } 677 *aip = NULL; 678 679 /* cleanup and return */ 680 free(aio); 681 free_addrselectpolicy(&policyhead); 682 return(n); 683 } 684 685 static int 686 get_addrselectpolicy(struct policyhead *head) 687 { 688 #ifdef INET6 689 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 690 size_t l; 691 char *buf; 692 struct in6_addrpolicy *pol, *ep; 693 694 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 695 return (0); 696 if (l == 0) 697 return (0); 698 if ((buf = malloc(l)) == NULL) 699 return (0); 700 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 701 free(buf); 702 return (0); 703 } 704 705 ep = (struct in6_addrpolicy *)(buf + l); 706 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 707 struct policyqueue *new; 708 709 if ((new = malloc(sizeof(*new))) == NULL) { 710 free_addrselectpolicy(head); /* make the list empty */ 711 break; 712 } 713 new->pc_policy = *pol; 714 TAILQ_INSERT_TAIL(head, new, pc_entry); 715 } 716 717 free(buf); 718 return (1); 719 #else 720 return (0); 721 #endif 722 } 723 724 static void 725 free_addrselectpolicy(struct policyhead *head) 726 { 727 struct policyqueue *ent, *nent; 728 729 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 730 nent = TAILQ_NEXT(ent, pc_entry); 731 TAILQ_REMOVE(head, ent, pc_entry); 732 free(ent); 733 } 734 } 735 736 static struct policyqueue * 737 match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 738 { 739 #ifdef INET6 740 struct policyqueue *ent, *bestent = NULL; 741 struct in6_addrpolicy *pol; 742 int matchlen, bestmatchlen = -1; 743 u_char *mp, *ep, *k, *p, m; 744 struct sockaddr_in6 key; 745 746 switch(addr->sa_family) { 747 case AF_INET6: 748 key = *(struct sockaddr_in6 *)addr; 749 break; 750 case AF_INET: 751 /* convert the address into IPv4-mapped IPv6 address. */ 752 memset(&key, 0, sizeof(key)); 753 key.sin6_family = AF_INET6; 754 key.sin6_len = sizeof(key); 755 key.sin6_addr.s6_addr[10] = 0xff; 756 key.sin6_addr.s6_addr[11] = 0xff; 757 memcpy(&key.sin6_addr.s6_addr[12], 758 &((struct sockaddr_in *)addr)->sin_addr, 4); 759 break; 760 default: 761 return(NULL); 762 } 763 764 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 765 pol = &ent->pc_policy; 766 matchlen = 0; 767 768 mp = (u_char *)&pol->addrmask.sin6_addr; 769 ep = mp + 16; /* XXX: scope field? */ 770 k = (u_char *)&key.sin6_addr; 771 p = (u_char *)&pol->addr.sin6_addr; 772 for (; mp < ep && *mp; mp++, k++, p++) { 773 m = *mp; 774 if ((*k & m) != *p) 775 goto next; /* not match */ 776 if (m == 0xff) /* short cut for a typical case */ 777 matchlen += 8; 778 else { 779 while (m >= 0x80) { 780 matchlen++; 781 m <<= 1; 782 } 783 } 784 } 785 786 /* matched. check if this is better than the current best. */ 787 if (matchlen > bestmatchlen) { 788 bestent = ent; 789 bestmatchlen = matchlen; 790 } 791 792 next: 793 continue; 794 } 795 796 return(bestent); 797 #else 798 return(NULL); 799 #endif 800 801 } 802 803 static void 804 set_source(struct ai_order *aio, struct policyhead *ph) 805 { 806 struct addrinfo ai = *aio->aio_ai; 807 struct sockaddr_storage ss; 808 socklen_t srclen; 809 int s; 810 811 /* set unspec ("no source is available"), just in case */ 812 aio->aio_srcsa.sa_family = AF_UNSPEC; 813 aio->aio_srcscope = -1; 814 815 switch(ai.ai_family) { 816 case AF_INET: 817 #ifdef INET6 818 case AF_INET6: 819 #endif 820 break; 821 default: /* ignore unsupported AFs explicitly */ 822 return; 823 } 824 825 /* XXX: make a dummy addrinfo to call connect() */ 826 ai.ai_socktype = SOCK_DGRAM; 827 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 828 ai.ai_next = NULL; 829 memset(&ss, 0, sizeof(ss)); 830 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 831 ai.ai_addr = (struct sockaddr *)&ss; 832 get_port(&ai, "1", 0); 833 834 /* open a socket to get the source address for the given dst */ 835 if ((s = _socket(ai.ai_family, ai.ai_socktype | SOCK_CLOEXEC, 836 ai.ai_protocol)) < 0) 837 return; /* give up */ 838 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 839 goto cleanup; 840 srclen = ai.ai_addrlen; 841 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 842 aio->aio_srcsa.sa_family = AF_UNSPEC; 843 goto cleanup; 844 } 845 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 846 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 847 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 848 #ifdef INET6 849 if (ai.ai_family == AF_INET6) { 850 struct in6_ifreq ifr6; 851 u_int32_t flags6; 852 853 memset(&ifr6, 0, sizeof(ifr6)); 854 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 855 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 856 flags6 = ifr6.ifr_ifru.ifru_flags6; 857 if ((flags6 & IN6_IFF_DEPRECATED)) 858 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 859 } 860 } 861 #endif 862 863 cleanup: 864 _close(s); 865 return; 866 } 867 868 static int 869 matchlen(struct sockaddr *src, struct sockaddr *dst) 870 { 871 int match = 0; 872 u_char *s, *d; 873 u_char *lim, r; 874 int addrlen; 875 876 switch (src->sa_family) { 877 #ifdef INET6 878 case AF_INET6: 879 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 880 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 881 addrlen = sizeof(struct in6_addr); 882 lim = s + addrlen; 883 break; 884 #endif 885 case AF_INET: 886 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; 887 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; 888 addrlen = sizeof(struct in_addr); 889 lim = s + addrlen; 890 break; 891 default: 892 return(0); 893 } 894 895 while (s < lim) 896 if ((r = (*d++ ^ *s++)) != 0) { 897 while (r < addrlen * 8) { 898 match++; 899 r <<= 1; 900 } 901 break; 902 } else 903 match += 8; 904 return(match); 905 } 906 907 static int 908 comp_dst(const void *arg1, const void *arg2) 909 { 910 const struct ai_order *dst1 = arg1, *dst2 = arg2; 911 912 /* 913 * Rule 1: Avoid unusable destinations. 914 * XXX: we currently do not consider if an appropriate route exists. 915 */ 916 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 917 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 918 return(-1); 919 } 920 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 921 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 922 return(1); 923 } 924 925 /* Rule 2: Prefer matching scope. */ 926 if (dst1->aio_dstscope == dst1->aio_srcscope && 927 dst2->aio_dstscope != dst2->aio_srcscope) { 928 return(-1); 929 } 930 if (dst1->aio_dstscope != dst1->aio_srcscope && 931 dst2->aio_dstscope == dst2->aio_srcscope) { 932 return(1); 933 } 934 935 /* Rule 3: Avoid deprecated addresses. */ 936 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 937 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 938 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 939 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 940 return(-1); 941 } 942 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 943 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 944 return(1); 945 } 946 } 947 948 /* Rule 4: Prefer home addresses. */ 949 /* XXX: not implemented yet */ 950 951 /* Rule 5: Prefer matching label. */ 952 #ifdef INET6 953 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 954 dst1->aio_srcpolicy->pc_policy.label == 955 dst1->aio_dstpolicy->pc_policy.label && 956 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 957 dst2->aio_srcpolicy->pc_policy.label != 958 dst2->aio_dstpolicy->pc_policy.label)) { 959 return(-1); 960 } 961 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 962 dst2->aio_srcpolicy->pc_policy.label == 963 dst2->aio_dstpolicy->pc_policy.label && 964 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 965 dst1->aio_srcpolicy->pc_policy.label != 966 dst1->aio_dstpolicy->pc_policy.label)) { 967 return(1); 968 } 969 #endif 970 971 /* Rule 6: Prefer higher precedence. */ 972 #ifdef INET6 973 if (dst1->aio_dstpolicy && 974 (dst2->aio_dstpolicy == NULL || 975 dst1->aio_dstpolicy->pc_policy.preced > 976 dst2->aio_dstpolicy->pc_policy.preced)) { 977 return(-1); 978 } 979 if (dst2->aio_dstpolicy && 980 (dst1->aio_dstpolicy == NULL || 981 dst2->aio_dstpolicy->pc_policy.preced > 982 dst1->aio_dstpolicy->pc_policy.preced)) { 983 return(1); 984 } 985 #endif 986 987 /* Rule 7: Prefer native transport. */ 988 /* XXX: not implemented yet */ 989 990 /* Rule 8: Prefer smaller scope. */ 991 if (dst1->aio_dstscope >= 0 && 992 dst1->aio_dstscope < dst2->aio_dstscope) { 993 return(-1); 994 } 995 if (dst2->aio_dstscope >= 0 && 996 dst2->aio_dstscope < dst1->aio_dstscope) { 997 return(1); 998 } 999 1000 /* 1001 * Rule 9: Use longest matching prefix. 1002 * We compare the match length in a same AF only. 1003 */ 1004 if (dst1->aio_ai->ai_addr->sa_family == 1005 dst2->aio_ai->ai_addr->sa_family && 1006 dst1->aio_ai->ai_addr->sa_family != AF_INET) { 1007 if (dst1->aio_matchlen > dst2->aio_matchlen) { 1008 return(-1); 1009 } 1010 if (dst1->aio_matchlen < dst2->aio_matchlen) { 1011 return(1); 1012 } 1013 } 1014 1015 /* Rule 10: Otherwise, leave the order unchanged. */ 1016 return(-1); 1017 } 1018 1019 /* 1020 * Copy from scope.c. 1021 * XXX: we should standardize the functions and link them as standard 1022 * library. 1023 */ 1024 static int 1025 gai_addr2scopetype(struct sockaddr *sa) 1026 { 1027 #ifdef INET6 1028 struct sockaddr_in6 *sa6; 1029 #endif 1030 struct sockaddr_in *sa4; 1031 1032 switch(sa->sa_family) { 1033 #ifdef INET6 1034 case AF_INET6: 1035 sa6 = (struct sockaddr_in6 *)sa; 1036 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1037 /* just use the scope field of the multicast address */ 1038 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1039 } 1040 /* 1041 * Unicast addresses: map scope type to corresponding scope 1042 * value defined for multcast addresses. 1043 * XXX: hardcoded scope type values are bad... 1044 */ 1045 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1046 return(1); /* node local scope */ 1047 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1048 return(2); /* link-local scope */ 1049 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1050 return(5); /* site-local scope */ 1051 return(14); /* global scope */ 1052 break; 1053 #endif 1054 case AF_INET: 1055 /* 1056 * IPv4 pseudo scoping according to RFC 3484. 1057 */ 1058 sa4 = (struct sockaddr_in *)sa; 1059 /* IPv4 autoconfiguration addresses have link-local scope. */ 1060 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1061 ((u_char *)&sa4->sin_addr)[1] == 254) 1062 return(2); 1063 /* Private addresses have site-local scope. */ 1064 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1065 (((u_char *)&sa4->sin_addr)[0] == 172 && 1066 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1067 (((u_char *)&sa4->sin_addr)[0] == 192 && 1068 ((u_char *)&sa4->sin_addr)[1] == 168)) 1069 return(14); /* XXX: It should be 5 unless NAT */ 1070 /* Loopback addresses have link-local scope. */ 1071 if (((u_char *)&sa4->sin_addr)[0] == 127) 1072 return(2); 1073 return(14); 1074 break; 1075 default: 1076 errno = EAFNOSUPPORT; /* is this a good error? */ 1077 return(-1); 1078 } 1079 } 1080 1081 static int 1082 explore_copy(const struct addrinfo *pai, const struct addrinfo *src0, 1083 struct addrinfo **res) 1084 { 1085 int error; 1086 struct addrinfo sentinel, *cur; 1087 const struct addrinfo *src; 1088 1089 error = 0; 1090 sentinel.ai_next = NULL; 1091 cur = &sentinel; 1092 1093 for (src = src0; src != NULL; src = src->ai_next) { 1094 if (src->ai_family != pai->ai_family) 1095 continue; 1096 1097 cur->ai_next = copy_ai(src); 1098 if (!cur->ai_next) { 1099 error = EAI_MEMORY; 1100 goto fail; 1101 } 1102 1103 cur->ai_next->ai_socktype = pai->ai_socktype; 1104 cur->ai_next->ai_protocol = pai->ai_protocol; 1105 cur = cur->ai_next; 1106 } 1107 1108 *res = sentinel.ai_next; 1109 return 0; 1110 1111 fail: 1112 freeaddrinfo(sentinel.ai_next); 1113 return error; 1114 } 1115 1116 /* 1117 * hostname == NULL. 1118 * passive socket -> anyaddr (0.0.0.0 or ::) 1119 * non-passive socket -> localhost (127.0.0.1 or ::1) 1120 */ 1121 static int 1122 explore_null(const struct addrinfo *pai, const char *servname, 1123 struct addrinfo **res) 1124 { 1125 int s; 1126 const struct afd *afd; 1127 struct addrinfo *ai; 1128 int error; 1129 1130 *res = NULL; 1131 ai = NULL; 1132 1133 /* 1134 * filter out AFs that are not supported by the kernel 1135 * XXX errno? 1136 */ 1137 s = _socket(pai->ai_family, SOCK_DGRAM | SOCK_CLOEXEC, 0); 1138 if (s < 0) { 1139 if (errno != EMFILE) 1140 return 0; 1141 } else 1142 _close(s); 1143 1144 afd = find_afd(pai->ai_family); 1145 if (afd == NULL) 1146 return 0; 1147 1148 if (pai->ai_flags & AI_PASSIVE) { 1149 GET_AI(ai, afd, afd->a_addrany); 1150 GET_PORT(ai, servname); 1151 } else { 1152 GET_AI(ai, afd, afd->a_loopback); 1153 GET_PORT(ai, servname); 1154 } 1155 1156 *res = ai; 1157 return 0; 1158 1159 free: 1160 if (ai != NULL) 1161 freeaddrinfo(ai); 1162 return error; 1163 } 1164 1165 /* 1166 * numeric hostname 1167 */ 1168 static int 1169 explore_numeric(const struct addrinfo *pai, const char *hostname, 1170 const char *servname, struct addrinfo **res, const char *canonname) 1171 { 1172 const struct afd *afd; 1173 struct addrinfo *ai; 1174 int error; 1175 char pton[PTON_MAX]; 1176 1177 *res = NULL; 1178 ai = NULL; 1179 1180 afd = find_afd(pai->ai_family); 1181 if (afd == NULL) 1182 return 0; 1183 1184 switch (afd->a_af) { 1185 case AF_INET: 1186 /* 1187 * RFC3493 requires getaddrinfo() to accept AF_INET formats 1188 * that are accepted by inet_addr() and its family. The 1189 * accepted forms includes the "classful" one, which inet_pton 1190 * does not accept. So we need to separate the case for 1191 * AF_INET. 1192 */ 1193 if (inet_aton(hostname, (struct in_addr *)pton) != 1) 1194 return 0; 1195 break; 1196 default: 1197 if (inet_pton(afd->a_af, hostname, pton) != 1) 1198 return 0; 1199 break; 1200 } 1201 1202 if (pai->ai_family == afd->a_af) { 1203 GET_AI(ai, afd, pton); 1204 GET_PORT(ai, servname); 1205 if ((pai->ai_flags & AI_CANONNAME)) { 1206 /* 1207 * Set the numeric address itself as the canonical 1208 * name, based on a clarification in RFC3493. 1209 */ 1210 GET_CANONNAME(ai, canonname); 1211 } 1212 } else { 1213 /* 1214 * XXX: This should not happen since we already matched the AF 1215 * by find_afd. 1216 */ 1217 ERR(EAI_FAMILY); 1218 } 1219 1220 *res = ai; 1221 return 0; 1222 1223 free: 1224 bad: 1225 if (ai != NULL) 1226 freeaddrinfo(ai); 1227 return error; 1228 } 1229 1230 /* 1231 * numeric hostname with scope 1232 */ 1233 static int 1234 explore_numeric_scope(const struct addrinfo *pai, const char *hostname, 1235 const char *servname, struct addrinfo **res) 1236 { 1237 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 1238 return explore_numeric(pai, hostname, servname, res, hostname); 1239 #else 1240 const struct afd *afd; 1241 struct addrinfo *cur; 1242 int error; 1243 char *cp, *hostname2 = NULL, *scope, *addr; 1244 struct sockaddr_in6 *sin6; 1245 1246 afd = find_afd(pai->ai_family); 1247 if (afd == NULL) 1248 return 0; 1249 1250 if (!afd->a_scoped) 1251 return explore_numeric(pai, hostname, servname, res, hostname); 1252 1253 cp = strchr(hostname, SCOPE_DELIMITER); 1254 if (cp == NULL) 1255 return explore_numeric(pai, hostname, servname, res, hostname); 1256 1257 /* 1258 * Handle special case of <scoped_address><delimiter><scope id> 1259 */ 1260 hostname2 = strdup(hostname); 1261 if (hostname2 == NULL) 1262 return EAI_MEMORY; 1263 /* terminate at the delimiter */ 1264 hostname2[cp - hostname] = '\0'; 1265 addr = hostname2; 1266 scope = cp + 1; 1267 1268 error = explore_numeric(pai, addr, servname, res, hostname); 1269 if (error == 0) { 1270 u_int32_t scopeid; 1271 1272 for (cur = *res; cur; cur = cur->ai_next) { 1273 if (cur->ai_family != AF_INET6) 1274 continue; 1275 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1276 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1277 free(hostname2); 1278 freeaddrinfo(*res); 1279 *res = NULL; 1280 return(EAI_NONAME); /* XXX: is return OK? */ 1281 } 1282 sin6->sin6_scope_id = scopeid; 1283 } 1284 } 1285 1286 free(hostname2); 1287 1288 if (error && *res) { 1289 freeaddrinfo(*res); 1290 *res = NULL; 1291 } 1292 return error; 1293 #endif 1294 } 1295 1296 static int 1297 get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) 1298 { 1299 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1300 ai->ai_canonname = strdup(str); 1301 if (ai->ai_canonname == NULL) 1302 return EAI_MEMORY; 1303 } 1304 return 0; 1305 } 1306 1307 static struct addrinfo * 1308 get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) 1309 { 1310 char *p; 1311 struct addrinfo *ai; 1312 1313 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1314 + (afd->a_socklen)); 1315 if (ai == NULL) 1316 return NULL; 1317 1318 memcpy(ai, pai, sizeof(struct addrinfo)); 1319 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1320 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1321 ai->ai_addr->sa_len = afd->a_socklen; 1322 ai->ai_addrlen = afd->a_socklen; 1323 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1324 p = (char *)(void *)(ai->ai_addr); 1325 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1326 return ai; 1327 } 1328 1329 /* XXX need to malloc() the same way we do from other functions! */ 1330 static struct addrinfo * 1331 copy_ai(const struct addrinfo *pai) 1332 { 1333 struct addrinfo *ai; 1334 size_t l; 1335 1336 l = sizeof(*ai) + pai->ai_addrlen; 1337 if ((ai = (struct addrinfo *)malloc(l)) == NULL) 1338 return NULL; 1339 memset(ai, 0, l); 1340 memcpy(ai, pai, sizeof(*ai)); 1341 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1342 memcpy(ai->ai_addr, pai->ai_addr, pai->ai_addrlen); 1343 1344 if (pai->ai_canonname) { 1345 l = strlen(pai->ai_canonname) + 1; 1346 if ((ai->ai_canonname = malloc(l)) == NULL) { 1347 free(ai); 1348 return NULL; 1349 } 1350 strlcpy(ai->ai_canonname, pai->ai_canonname, l); 1351 } else { 1352 /* just to make sure */ 1353 ai->ai_canonname = NULL; 1354 } 1355 1356 ai->ai_next = NULL; 1357 1358 return ai; 1359 } 1360 1361 static int 1362 get_portmatch(const struct addrinfo *ai, const char *servname) 1363 { 1364 1365 /* get_port does not touch first argument when matchonly == 1. */ 1366 /* LINTED const cast */ 1367 return get_port((struct addrinfo *)ai, servname, 1); 1368 } 1369 1370 static int 1371 get_port(struct addrinfo *ai, const char *servname, int matchonly) 1372 { 1373 const char *proto; 1374 struct servent *sp; 1375 int port, error; 1376 int allownumeric; 1377 1378 if (servname == NULL) 1379 return 0; 1380 switch (ai->ai_family) { 1381 case AF_INET: 1382 #ifdef AF_INET6 1383 case AF_INET6: 1384 #endif 1385 break; 1386 default: 1387 return 0; 1388 } 1389 1390 switch (ai->ai_socktype) { 1391 case SOCK_RAW: 1392 return EAI_SERVICE; 1393 case SOCK_DGRAM: 1394 case SOCK_STREAM: 1395 case SOCK_SEQPACKET: 1396 allownumeric = 1; 1397 break; 1398 case ANY: 1399 switch (ai->ai_family) { 1400 case AF_INET: 1401 #ifdef AF_INET6 1402 case AF_INET6: 1403 #endif 1404 allownumeric = 1; 1405 break; 1406 default: 1407 allownumeric = 0; 1408 break; 1409 } 1410 break; 1411 default: 1412 return EAI_SOCKTYPE; 1413 } 1414 1415 error = str2number(servname, &port); 1416 if (error == 0) { 1417 if (!allownumeric) 1418 return EAI_SERVICE; 1419 if (port < 0 || port > 65535) 1420 return EAI_SERVICE; 1421 port = htons(port); 1422 } else { 1423 if (ai->ai_flags & AI_NUMERICSERV) 1424 return EAI_NONAME; 1425 1426 switch (ai->ai_protocol) { 1427 case IPPROTO_UDP: 1428 proto = "udp"; 1429 break; 1430 case IPPROTO_TCP: 1431 proto = "tcp"; 1432 break; 1433 case IPPROTO_SCTP: 1434 proto = "sctp"; 1435 break; 1436 case IPPROTO_UDPLITE: 1437 proto = "udplite"; 1438 break; 1439 default: 1440 proto = NULL; 1441 break; 1442 } 1443 1444 if ((sp = getservbyname(servname, proto)) == NULL) 1445 return EAI_SERVICE; 1446 port = sp->s_port; 1447 } 1448 1449 if (!matchonly) { 1450 switch (ai->ai_family) { 1451 case AF_INET: 1452 ((struct sockaddr_in *)(void *) 1453 ai->ai_addr)->sin_port = port; 1454 break; 1455 #ifdef INET6 1456 case AF_INET6: 1457 ((struct sockaddr_in6 *)(void *) 1458 ai->ai_addr)->sin6_port = port; 1459 break; 1460 #endif 1461 } 1462 } 1463 1464 return 0; 1465 } 1466 1467 static const struct afd * 1468 find_afd(int af) 1469 { 1470 const struct afd *afd; 1471 1472 if (af == PF_UNSPEC) 1473 return NULL; 1474 for (afd = afdl; afd->a_af; afd++) { 1475 if (afd->a_af == af) 1476 return afd; 1477 } 1478 return NULL; 1479 } 1480 1481 /* 1482 * RFC 3493: AI_ADDRCONFIG check. Determines which address families are 1483 * configured on the local system and correlates with pai->ai_family value. 1484 * If an address family is not configured on the system, it will not be 1485 * queried for. For this purpose, loopback addresses are not considered 1486 * configured addresses. 1487 * 1488 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1489 * _dns_getaddrinfo. 1490 */ 1491 static int 1492 addrconfig(struct addrinfo *pai) 1493 { 1494 struct ifaddrs *ifaddrs, *ifa; 1495 struct sockaddr_in *sin; 1496 #ifdef INET6 1497 struct sockaddr_in6 *sin6; 1498 #endif 1499 int seen_inet = 0, seen_inet6 = 0; 1500 1501 if (getifaddrs(&ifaddrs) != 0) 1502 return (0); 1503 1504 for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) { 1505 if (ifa->ifa_addr == NULL || (ifa->ifa_flags & IFF_UP) == 0) 1506 continue; 1507 switch (ifa->ifa_addr->sa_family) { 1508 case AF_INET: 1509 if (seen_inet) 1510 continue; 1511 sin = (struct sockaddr_in *)(ifa->ifa_addr); 1512 if (IN_LOOPBACK(htonl(sin->sin_addr.s_addr))) 1513 continue; 1514 seen_inet = 1; 1515 break; 1516 #ifdef INET6 1517 case AF_INET6: 1518 if (seen_inet6) 1519 continue; 1520 sin6 = (struct sockaddr_in6 *)(ifa->ifa_addr); 1521 if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr)) 1522 continue; 1523 if ((ifa->ifa_flags & IFT_LOOP) != 0 && 1524 IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) 1525 continue; 1526 if (is_ifdisabled(ifa->ifa_name)) 1527 continue; 1528 seen_inet6 = 1; 1529 break; 1530 #endif 1531 } 1532 } 1533 freeifaddrs(ifaddrs); 1534 1535 switch(pai->ai_family) { 1536 case AF_INET6: 1537 return (seen_inet6); 1538 case AF_INET: 1539 return (seen_inet); 1540 case AF_UNSPEC: 1541 if (seen_inet == seen_inet6) 1542 return (seen_inet); 1543 pai->ai_family = seen_inet ? AF_INET : AF_INET6; 1544 return (1); 1545 } 1546 return (1); 1547 } 1548 1549 #ifdef INET6 1550 static int 1551 is_ifdisabled(char *name) 1552 { 1553 struct in6_ndireq nd; 1554 int fd; 1555 1556 if ((fd = _socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, 0)) < 0) 1557 return (-1); 1558 memset(&nd, 0, sizeof(nd)); 1559 strlcpy(nd.ifname, name, sizeof(nd.ifname)); 1560 if (_ioctl(fd, SIOCGIFINFO_IN6, &nd) < 0) { 1561 _close(fd); 1562 return (-1); 1563 } 1564 _close(fd); 1565 return ((nd.ndi.flags & ND6_IFF_IFDISABLED) != 0); 1566 } 1567 1568 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1569 static int 1570 ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid) 1571 { 1572 u_long lscopeid; 1573 struct in6_addr *a6; 1574 char *ep; 1575 1576 a6 = &sin6->sin6_addr; 1577 1578 /* empty scopeid portion is invalid */ 1579 if (*scope == '\0') 1580 return -1; 1581 1582 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6) || 1583 IN6_IS_ADDR_MC_NODELOCAL(a6)) { 1584 /* 1585 * We currently assume a one-to-one mapping between links 1586 * and interfaces, so we simply use interface indices for 1587 * like-local scopes. 1588 */ 1589 *scopeid = if_nametoindex(scope); 1590 if (*scopeid == 0) 1591 goto trynumeric; 1592 return 0; 1593 } 1594 1595 /* still unclear about literal, allow numeric only - placeholder */ 1596 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1597 goto trynumeric; 1598 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1599 goto trynumeric; 1600 else 1601 goto trynumeric; /* global */ 1602 1603 /* try to convert to a numeric id as a last resort */ 1604 trynumeric: 1605 errno = 0; 1606 lscopeid = strtoul(scope, &ep, 10); 1607 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1608 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1609 return 0; 1610 else 1611 return -1; 1612 } 1613 #endif 1614 1615 1616 #ifdef NS_CACHING 1617 static int 1618 addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap, 1619 void *cache_mdata) 1620 { 1621 res_state statp; 1622 u_long res_options; 1623 1624 const int op_id = 0; /* identifies the getaddrinfo for the cache */ 1625 char *hostname; 1626 struct addrinfo *hints; 1627 1628 char *p; 1629 int ai_flags, ai_family, ai_socktype, ai_protocol; 1630 size_t desired_size, size; 1631 1632 statp = __res_state(); 1633 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES | 1634 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6); 1635 1636 hostname = va_arg(ap, char *); 1637 hints = va_arg(ap, struct addrinfo *); 1638 1639 desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4; 1640 if (hostname != NULL) { 1641 size = strlen(hostname); 1642 desired_size += size + 1; 1643 } else 1644 size = 0; 1645 1646 if (desired_size > *buffer_size) { 1647 *buffer_size = desired_size; 1648 return (NS_RETURN); 1649 } 1650 1651 if (hints == NULL) 1652 ai_flags = ai_family = ai_socktype = ai_protocol = 0; 1653 else { 1654 ai_flags = hints->ai_flags; 1655 ai_family = hints->ai_family; 1656 ai_socktype = hints->ai_socktype; 1657 ai_protocol = hints->ai_protocol; 1658 } 1659 1660 p = buffer; 1661 memcpy(p, &res_options, sizeof(res_options)); 1662 p += sizeof(res_options); 1663 1664 memcpy(p, &op_id, sizeof(int)); 1665 p += sizeof(int); 1666 1667 memcpy(p, &ai_flags, sizeof(int)); 1668 p += sizeof(int); 1669 1670 memcpy(p, &ai_family, sizeof(int)); 1671 p += sizeof(int); 1672 1673 memcpy(p, &ai_socktype, sizeof(int)); 1674 p += sizeof(int); 1675 1676 memcpy(p, &ai_protocol, sizeof(int)); 1677 p += sizeof(int); 1678 1679 if (hostname != NULL) 1680 memcpy(p, hostname, size); 1681 1682 *buffer_size = desired_size; 1683 return (NS_SUCCESS); 1684 } 1685 1686 static int 1687 addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval, 1688 va_list ap, void *cache_mdata) 1689 { 1690 struct addrinfo *ai, *cai; 1691 char *p; 1692 size_t desired_size, size, ai_size; 1693 1694 ai = *((struct addrinfo **)retval); 1695 1696 desired_size = sizeof(size_t); 1697 ai_size = 0; 1698 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1699 desired_size += sizeof(struct addrinfo) + cai->ai_addrlen; 1700 if (cai->ai_canonname != NULL) 1701 desired_size += sizeof(size_t) + 1702 strlen(cai->ai_canonname); 1703 ++ai_size; 1704 } 1705 1706 if (desired_size > *buffer_size) { 1707 /* this assignment is here for future use */ 1708 errno = ERANGE; 1709 *buffer_size = desired_size; 1710 return (NS_RETURN); 1711 } 1712 1713 memset(buffer, 0, desired_size); 1714 p = buffer; 1715 1716 memcpy(p, &ai_size, sizeof(size_t)); 1717 p += sizeof(size_t); 1718 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1719 memcpy(p, cai, sizeof(struct addrinfo)); 1720 p += sizeof(struct addrinfo); 1721 1722 memcpy(p, cai->ai_addr, cai->ai_addrlen); 1723 p += cai->ai_addrlen; 1724 1725 if (cai->ai_canonname != NULL) { 1726 size = strlen(cai->ai_canonname); 1727 memcpy(p, &size, sizeof(size_t)); 1728 p += sizeof(size_t); 1729 1730 memcpy(p, cai->ai_canonname, size); 1731 p += size; 1732 } 1733 } 1734 1735 return (NS_SUCCESS); 1736 } 1737 1738 static int 1739 addrinfo_unmarshal_func(char *buffer, size_t buffer_size, void *retval, 1740 va_list ap, void *cache_mdata) 1741 { 1742 struct addrinfo new_ai, *result, *sentinel, *lasts; 1743 1744 char *p; 1745 size_t ai_size, ai_i, size; 1746 1747 p = buffer; 1748 memcpy(&ai_size, p, sizeof(size_t)); 1749 p += sizeof(size_t); 1750 1751 result = NULL; 1752 lasts = NULL; 1753 for (ai_i = 0; ai_i < ai_size; ++ai_i) { 1754 memcpy(&new_ai, p, sizeof(struct addrinfo)); 1755 p += sizeof(struct addrinfo); 1756 size = new_ai.ai_addrlen + sizeof(struct addrinfo) + 1757 _ALIGNBYTES; 1758 1759 sentinel = (struct addrinfo *)malloc(size); 1760 memset(sentinel, 0, size); 1761 1762 memcpy(sentinel, &new_ai, sizeof(struct addrinfo)); 1763 sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel + 1764 sizeof(struct addrinfo)); 1765 1766 memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen); 1767 p += new_ai.ai_addrlen; 1768 1769 if (new_ai.ai_canonname != NULL) { 1770 memcpy(&size, p, sizeof(size_t)); 1771 p += sizeof(size_t); 1772 1773 sentinel->ai_canonname = (char *)malloc(size + 1); 1774 memset(sentinel->ai_canonname, 0, size + 1); 1775 1776 memcpy(sentinel->ai_canonname, p, size); 1777 p += size; 1778 } 1779 1780 if (result == NULL) { 1781 result = sentinel; 1782 lasts = sentinel; 1783 } else { 1784 lasts->ai_next = sentinel; 1785 lasts = sentinel; 1786 } 1787 } 1788 1789 *((struct addrinfo **)retval) = result; 1790 return (NS_SUCCESS); 1791 } 1792 #endif /* NS_CACHING */ 1793 1794 /* 1795 * FQDN hostname, DNS lookup 1796 */ 1797 static int 1798 explore_fqdn(const struct addrinfo *pai, const char *hostname, 1799 const char *servname, struct addrinfo **res) 1800 { 1801 struct addrinfo *result; 1802 struct addrinfo *cur; 1803 int error = 0; 1804 1805 #ifdef NS_CACHING 1806 static const nss_cache_info cache_info = 1807 NS_COMMON_CACHE_INFO_INITIALIZER( 1808 hosts, NULL, addrinfo_id_func, addrinfo_marshal_func, 1809 addrinfo_unmarshal_func); 1810 #endif 1811 static const ns_dtab dtab[] = { 1812 NS_FILES_CB(_files_getaddrinfo, NULL) 1813 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1814 NS_NIS_CB(_yp_getaddrinfo, NULL) 1815 #ifdef NS_CACHING 1816 NS_CACHE_CB(&cache_info) 1817 #endif 1818 { 0 } 1819 }; 1820 1821 result = NULL; 1822 1823 /* 1824 * if the servname does not match socktype/protocol, ignore it. 1825 */ 1826 if (get_portmatch(pai, servname) != 0) 1827 return 0; 1828 1829 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1830 default_dns_files, hostname, pai)) { 1831 case NS_TRYAGAIN: 1832 error = EAI_AGAIN; 1833 goto free; 1834 case NS_UNAVAIL: 1835 error = EAI_FAIL; 1836 goto free; 1837 case NS_NOTFOUND: 1838 error = EAI_NONAME; 1839 goto free; 1840 case NS_SUCCESS: 1841 error = 0; 1842 for (cur = result; cur; cur = cur->ai_next) { 1843 GET_PORT(cur, servname); 1844 /* canonname should be filled already */ 1845 } 1846 break; 1847 } 1848 1849 *res = result; 1850 1851 return 0; 1852 1853 free: 1854 if (result) 1855 freeaddrinfo(result); 1856 return error; 1857 } 1858 1859 #ifdef DEBUG 1860 static const char AskedForGot[] = 1861 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1862 #endif 1863 1864 static struct addrinfo * 1865 getanswer(const querybuf *answer, int anslen, const char *qname, int qtype, 1866 const struct addrinfo *pai, res_state res) 1867 { 1868 struct addrinfo sentinel, *cur; 1869 struct addrinfo ai; 1870 const struct afd *afd; 1871 char *canonname; 1872 const HEADER *hp; 1873 const u_char *cp; 1874 int n; 1875 const u_char *eom; 1876 char *bp, *ep; 1877 int type, class, ancount, qdcount; 1878 int haveanswer, had_error; 1879 char tbuf[MAXDNAME]; 1880 int (*name_ok)(const char *); 1881 char hostbuf[8*1024]; 1882 1883 memset(&sentinel, 0, sizeof(sentinel)); 1884 cur = &sentinel; 1885 1886 canonname = NULL; 1887 eom = answer->buf + anslen; 1888 switch (qtype) { 1889 case T_A: 1890 case T_AAAA: 1891 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1892 name_ok = res_hnok; 1893 break; 1894 default: 1895 return (NULL); /* XXX should be abort(); */ 1896 } 1897 /* 1898 * find first satisfactory answer 1899 */ 1900 hp = &answer->hdr; 1901 ancount = ntohs(hp->ancount); 1902 qdcount = ntohs(hp->qdcount); 1903 bp = hostbuf; 1904 ep = hostbuf + sizeof hostbuf; 1905 cp = answer->buf + HFIXEDSZ; 1906 if (qdcount != 1) { 1907 RES_SET_H_ERRNO(res, NO_RECOVERY); 1908 return (NULL); 1909 } 1910 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1911 if ((n < 0) || !(*name_ok)(bp)) { 1912 RES_SET_H_ERRNO(res, NO_RECOVERY); 1913 return (NULL); 1914 } 1915 cp += n + QFIXEDSZ; 1916 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1917 /* res_send() has already verified that the query name is the 1918 * same as the one we sent; this just gets the expanded name 1919 * (i.e., with the succeeding search-domain tacked on). 1920 */ 1921 n = strlen(bp) + 1; /* for the \0 */ 1922 if (n >= MAXHOSTNAMELEN) { 1923 RES_SET_H_ERRNO(res, NO_RECOVERY); 1924 return (NULL); 1925 } 1926 canonname = bp; 1927 bp += n; 1928 /* The qname can be abbreviated, but h_name is now absolute. */ 1929 qname = canonname; 1930 } 1931 haveanswer = 0; 1932 had_error = 0; 1933 while (ancount-- > 0 && cp < eom && !had_error) { 1934 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1935 if ((n < 0) || !(*name_ok)(bp)) { 1936 had_error++; 1937 continue; 1938 } 1939 cp += n; /* name */ 1940 type = _getshort(cp); 1941 cp += INT16SZ; /* type */ 1942 class = _getshort(cp); 1943 cp += INT16SZ + INT32SZ; /* class, TTL */ 1944 n = _getshort(cp); 1945 cp += INT16SZ; /* len */ 1946 if (class != C_IN) { 1947 /* XXX - debug? syslog? */ 1948 cp += n; 1949 continue; /* XXX - had_error++ ? */ 1950 } 1951 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1952 type == T_CNAME) { 1953 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1954 if ((n < 0) || !(*name_ok)(tbuf)) { 1955 had_error++; 1956 continue; 1957 } 1958 cp += n; 1959 /* Get canonical name. */ 1960 n = strlen(tbuf) + 1; /* for the \0 */ 1961 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1962 had_error++; 1963 continue; 1964 } 1965 strlcpy(bp, tbuf, ep - bp); 1966 canonname = bp; 1967 bp += n; 1968 continue; 1969 } 1970 if (qtype == T_ANY) { 1971 if (!(type == T_A || type == T_AAAA)) { 1972 cp += n; 1973 continue; 1974 } 1975 } else if (type != qtype) { 1976 #ifdef DEBUG 1977 if (type != T_KEY && type != T_SIG && 1978 type != ns_t_dname) 1979 syslog(LOG_NOTICE|LOG_AUTH, 1980 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1981 qname, p_class(C_IN), p_type(qtype), 1982 p_type(type)); 1983 #endif 1984 cp += n; 1985 continue; /* XXX - had_error++ ? */ 1986 } 1987 switch (type) { 1988 case T_A: 1989 case T_AAAA: 1990 if (strcasecmp(canonname, bp) != 0) { 1991 #ifdef DEBUG 1992 syslog(LOG_NOTICE|LOG_AUTH, 1993 AskedForGot, canonname, bp); 1994 #endif 1995 cp += n; 1996 continue; /* XXX - had_error++ ? */ 1997 } 1998 if (type == T_A && n != INADDRSZ) { 1999 cp += n; 2000 continue; 2001 } 2002 if (type == T_AAAA && n != IN6ADDRSZ) { 2003 cp += n; 2004 continue; 2005 } 2006 #ifdef FILTER_V4MAPPED 2007 if (type == T_AAAA) { 2008 struct in6_addr in6; 2009 memcpy(&in6, cp, sizeof(in6)); 2010 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 2011 cp += n; 2012 continue; 2013 } 2014 } 2015 #endif 2016 if (!haveanswer) { 2017 int nn; 2018 2019 canonname = bp; 2020 nn = strlen(bp) + 1; /* for the \0 */ 2021 bp += nn; 2022 } 2023 2024 /* don't overwrite pai */ 2025 ai = *pai; 2026 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 2027 afd = find_afd(ai.ai_family); 2028 if (afd == NULL) { 2029 cp += n; 2030 continue; 2031 } 2032 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 2033 if (cur->ai_next == NULL) 2034 had_error++; 2035 while (cur && cur->ai_next) 2036 cur = cur->ai_next; 2037 cp += n; 2038 break; 2039 default: 2040 abort(); 2041 } 2042 if (!had_error) 2043 haveanswer++; 2044 } 2045 if (haveanswer) { 2046 #if defined(RESOLVSORT) 2047 /* 2048 * We support only IPv4 address for backward 2049 * compatibility against gethostbyname(3). 2050 */ 2051 if (res->nsort && qtype == T_A) { 2052 if (addr4sort(&sentinel, res) < 0) { 2053 freeaddrinfo(sentinel.ai_next); 2054 RES_SET_H_ERRNO(res, NO_RECOVERY); 2055 return NULL; 2056 } 2057 } 2058 #endif /*RESOLVSORT*/ 2059 if (!canonname) 2060 (void)get_canonname(pai, sentinel.ai_next, qname); 2061 else 2062 (void)get_canonname(pai, sentinel.ai_next, canonname); 2063 RES_SET_H_ERRNO(res, NETDB_SUCCESS); 2064 return sentinel.ai_next; 2065 } 2066 2067 RES_SET_H_ERRNO(res, NO_RECOVERY); 2068 return NULL; 2069 } 2070 2071 #ifdef RESOLVSORT 2072 struct addr_ptr { 2073 struct addrinfo *ai; 2074 int aval; 2075 }; 2076 2077 static int 2078 addr4sort(struct addrinfo *sentinel, res_state res) 2079 { 2080 struct addrinfo *ai; 2081 struct addr_ptr *addrs, addr; 2082 struct sockaddr_in *sin; 2083 int naddrs, i, j; 2084 int needsort = 0; 2085 2086 if (!sentinel) 2087 return -1; 2088 naddrs = 0; 2089 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 2090 naddrs++; 2091 if (naddrs < 2) 2092 return 0; /* We don't need sorting. */ 2093 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 2094 return -1; 2095 i = 0; 2096 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 2097 sin = (struct sockaddr_in *)ai->ai_addr; 2098 for (j = 0; (unsigned)j < res->nsort; j++) { 2099 if (res->sort_list[j].addr.s_addr == 2100 (sin->sin_addr.s_addr & res->sort_list[j].mask)) 2101 break; 2102 } 2103 addrs[i].ai = ai; 2104 addrs[i].aval = j; 2105 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 2106 needsort = i; 2107 i++; 2108 } 2109 if (!needsort) { 2110 free(addrs); 2111 return 0; 2112 } 2113 2114 while (needsort < naddrs) { 2115 for (j = needsort - 1; j >= 0; j--) { 2116 if (addrs[j].aval > addrs[j+1].aval) { 2117 addr = addrs[j]; 2118 addrs[j] = addrs[j + 1]; 2119 addrs[j + 1] = addr; 2120 } else 2121 break; 2122 } 2123 needsort++; 2124 } 2125 2126 ai = sentinel; 2127 for (i = 0; i < naddrs; ++i) { 2128 ai->ai_next = addrs[i].ai; 2129 ai = ai->ai_next; 2130 } 2131 ai->ai_next = NULL; 2132 free(addrs); 2133 return 0; 2134 } 2135 #endif /*RESOLVSORT*/ 2136 2137 /*ARGSUSED*/ 2138 static int 2139 _dns_getaddrinfo(void *rv, void *cb_data, va_list ap) 2140 { 2141 struct addrinfo *ai; 2142 querybuf *buf, *buf2; 2143 const char *hostname; 2144 const struct addrinfo *pai; 2145 struct addrinfo sentinel, *cur; 2146 struct res_target q, q2; 2147 res_state res; 2148 2149 hostname = va_arg(ap, char *); 2150 pai = va_arg(ap, const struct addrinfo *); 2151 2152 memset(&q, 0, sizeof(q)); 2153 memset(&q2, 0, sizeof(q2)); 2154 memset(&sentinel, 0, sizeof(sentinel)); 2155 cur = &sentinel; 2156 2157 buf = malloc(sizeof(*buf)); 2158 if (!buf) { 2159 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2160 return NS_NOTFOUND; 2161 } 2162 buf2 = malloc(sizeof(*buf2)); 2163 if (!buf2) { 2164 free(buf); 2165 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2166 return NS_NOTFOUND; 2167 } 2168 2169 switch (pai->ai_family) { 2170 case AF_UNSPEC: 2171 q.name = hostname; 2172 q.qclass = C_IN; 2173 q.qtype = T_A; 2174 q.answer = buf->buf; 2175 q.anslen = sizeof(buf->buf); 2176 q.next = &q2; 2177 q2.name = hostname; 2178 q2.qclass = C_IN; 2179 q2.qtype = T_AAAA; 2180 q2.answer = buf2->buf; 2181 q2.anslen = sizeof(buf2->buf); 2182 break; 2183 case AF_INET: 2184 q.name = hostname; 2185 q.qclass = C_IN; 2186 q.qtype = T_A; 2187 q.answer = buf->buf; 2188 q.anslen = sizeof(buf->buf); 2189 break; 2190 case AF_INET6: 2191 q.name = hostname; 2192 q.qclass = C_IN; 2193 q.qtype = T_AAAA; 2194 q.answer = buf->buf; 2195 q.anslen = sizeof(buf->buf); 2196 break; 2197 default: 2198 free(buf); 2199 free(buf2); 2200 return NS_UNAVAIL; 2201 } 2202 2203 res = __res_state(); 2204 if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) { 2205 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2206 free(buf); 2207 free(buf2); 2208 return NS_NOTFOUND; 2209 } 2210 2211 if (res_searchN(hostname, &q, res) < 0) { 2212 free(buf); 2213 free(buf2); 2214 return NS_NOTFOUND; 2215 } 2216 /* prefer IPv6 */ 2217 if (q.next) { 2218 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res); 2219 if (ai) { 2220 cur->ai_next = ai; 2221 while (cur && cur->ai_next) 2222 cur = cur->ai_next; 2223 } 2224 } 2225 ai = getanswer(buf, q.n, q.name, q.qtype, pai, res); 2226 if (ai) 2227 cur->ai_next = ai; 2228 free(buf); 2229 free(buf2); 2230 if (sentinel.ai_next == NULL) 2231 switch (res->res_h_errno) { 2232 case HOST_NOT_FOUND: 2233 return NS_NOTFOUND; 2234 case TRY_AGAIN: 2235 return NS_TRYAGAIN; 2236 default: 2237 return NS_UNAVAIL; 2238 } 2239 *((struct addrinfo **)rv) = sentinel.ai_next; 2240 return NS_SUCCESS; 2241 } 2242 2243 static void 2244 _sethtent(FILE **hostf) 2245 { 2246 if (!*hostf) 2247 *hostf = fopen(_PATH_HOSTS, "re"); 2248 else 2249 rewind(*hostf); 2250 } 2251 2252 static void 2253 _endhtent(FILE **hostf) 2254 { 2255 if (*hostf) { 2256 (void) fclose(*hostf); 2257 *hostf = NULL; 2258 } 2259 } 2260 2261 static struct addrinfo * 2262 _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2263 { 2264 char *p; 2265 char *cp, *tname, *cname; 2266 struct addrinfo hints, *res0, *res; 2267 int error; 2268 const char *addr; 2269 char hostbuf[8*1024]; 2270 2271 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "re"))) 2272 return (NULL); 2273 again: 2274 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 2275 return (NULL); 2276 if (*p == '#') 2277 goto again; 2278 cp = strpbrk(p, "#\n"); 2279 if (cp != NULL) 2280 *cp = '\0'; 2281 if (!(cp = strpbrk(p, " \t"))) 2282 goto again; 2283 *cp++ = '\0'; 2284 addr = p; 2285 cname = NULL; 2286 /* if this is not something we're looking for, skip it. */ 2287 while (cp && *cp) { 2288 if (*cp == ' ' || *cp == '\t') { 2289 cp++; 2290 continue; 2291 } 2292 tname = cp; 2293 if (cname == NULL) 2294 cname = cp; 2295 if ((cp = strpbrk(cp, " \t")) != NULL) 2296 *cp++ = '\0'; 2297 if (strcasecmp(name, tname) == 0) 2298 goto found; 2299 } 2300 goto again; 2301 2302 found: 2303 /* we should not glob socktype/protocol here */ 2304 memset(&hints, 0, sizeof(hints)); 2305 hints.ai_family = pai->ai_family; 2306 hints.ai_socktype = SOCK_DGRAM; 2307 hints.ai_protocol = 0; 2308 hints.ai_flags = AI_NUMERICHOST; 2309 error = getaddrinfo(addr, "0", &hints, &res0); 2310 if (error) 2311 goto again; 2312 #ifdef FILTER_V4MAPPED 2313 /* XXX should check all items in the chain */ 2314 if (res0->ai_family == AF_INET6 && 2315 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2316 freeaddrinfo(res0); 2317 goto again; 2318 } 2319 #endif 2320 for (res = res0; res; res = res->ai_next) { 2321 /* cover it up */ 2322 res->ai_flags = pai->ai_flags; 2323 res->ai_socktype = pai->ai_socktype; 2324 res->ai_protocol = pai->ai_protocol; 2325 2326 if (pai->ai_flags & AI_CANONNAME) { 2327 if (get_canonname(pai, res, cname) != 0) { 2328 freeaddrinfo(res0); 2329 goto again; 2330 } 2331 } 2332 } 2333 return res0; 2334 } 2335 2336 /*ARGSUSED*/ 2337 static int 2338 _files_getaddrinfo(void *rv, void *cb_data, va_list ap) 2339 { 2340 const char *name; 2341 const struct addrinfo *pai; 2342 struct addrinfo sentinel, *cur; 2343 struct addrinfo *p; 2344 FILE *hostf = NULL; 2345 2346 name = va_arg(ap, char *); 2347 pai = va_arg(ap, struct addrinfo *); 2348 2349 memset(&sentinel, 0, sizeof(sentinel)); 2350 cur = &sentinel; 2351 2352 _sethtent(&hostf); 2353 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2354 cur->ai_next = p; 2355 while (cur && cur->ai_next) 2356 cur = cur->ai_next; 2357 } 2358 _endhtent(&hostf); 2359 2360 *((struct addrinfo **)rv) = sentinel.ai_next; 2361 if (sentinel.ai_next == NULL) 2362 return NS_NOTFOUND; 2363 return NS_SUCCESS; 2364 } 2365 2366 #ifdef YP 2367 /*ARGSUSED*/ 2368 static struct addrinfo * 2369 _yphostent(char *line, const struct addrinfo *pai) 2370 { 2371 struct addrinfo sentinel, *cur; 2372 struct addrinfo hints, *res, *res0; 2373 int error; 2374 char *p = line; 2375 const char *addr, *canonname; 2376 char *nextline; 2377 char *cp; 2378 2379 addr = canonname = NULL; 2380 2381 memset(&sentinel, 0, sizeof(sentinel)); 2382 cur = &sentinel; 2383 2384 nextline: 2385 /* terminate line */ 2386 cp = strchr(p, '\n'); 2387 if (cp) { 2388 *cp++ = '\0'; 2389 nextline = cp; 2390 } else 2391 nextline = NULL; 2392 2393 cp = strpbrk(p, " \t"); 2394 if (cp == NULL) { 2395 if (canonname == NULL) 2396 return (NULL); 2397 else 2398 goto done; 2399 } 2400 *cp++ = '\0'; 2401 2402 addr = p; 2403 2404 while (cp && *cp) { 2405 if (*cp == ' ' || *cp == '\t') { 2406 cp++; 2407 continue; 2408 } 2409 if (!canonname) 2410 canonname = cp; 2411 if ((cp = strpbrk(cp, " \t")) != NULL) 2412 *cp++ = '\0'; 2413 } 2414 2415 hints = *pai; 2416 hints.ai_flags = AI_NUMERICHOST; 2417 error = getaddrinfo(addr, NULL, &hints, &res0); 2418 if (error == 0) { 2419 for (res = res0; res; res = res->ai_next) { 2420 /* cover it up */ 2421 res->ai_flags = pai->ai_flags; 2422 2423 if (pai->ai_flags & AI_CANONNAME) 2424 (void)get_canonname(pai, res, canonname); 2425 } 2426 } else 2427 res0 = NULL; 2428 if (res0) { 2429 cur->ai_next = res0; 2430 while (cur && cur->ai_next) 2431 cur = cur->ai_next; 2432 } 2433 2434 if (nextline) { 2435 p = nextline; 2436 goto nextline; 2437 } 2438 2439 done: 2440 return sentinel.ai_next; 2441 } 2442 2443 /*ARGSUSED*/ 2444 static int 2445 _yp_getaddrinfo(void *rv, void *cb_data, va_list ap) 2446 { 2447 struct addrinfo sentinel, *cur; 2448 struct addrinfo *ai = NULL; 2449 char *ypbuf; 2450 int ypbuflen, r; 2451 const char *name; 2452 const struct addrinfo *pai; 2453 char *ypdomain; 2454 2455 if (_yp_check(&ypdomain) == 0) 2456 return NS_UNAVAIL; 2457 2458 name = va_arg(ap, char *); 2459 pai = va_arg(ap, const struct addrinfo *); 2460 2461 memset(&sentinel, 0, sizeof(sentinel)); 2462 cur = &sentinel; 2463 2464 /* hosts.byname is only for IPv4 (Solaris8) */ 2465 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2466 r = yp_match(ypdomain, "hosts.byname", name, 2467 (int)strlen(name), &ypbuf, &ypbuflen); 2468 if (r == 0) { 2469 struct addrinfo ai4; 2470 2471 ai4 = *pai; 2472 ai4.ai_family = AF_INET; 2473 ai = _yphostent(ypbuf, &ai4); 2474 if (ai) { 2475 cur->ai_next = ai; 2476 while (cur && cur->ai_next) 2477 cur = cur->ai_next; 2478 } 2479 free(ypbuf); 2480 } 2481 } 2482 2483 /* ipnodes.byname can hold both IPv4/v6 */ 2484 r = yp_match(ypdomain, "ipnodes.byname", name, 2485 (int)strlen(name), &ypbuf, &ypbuflen); 2486 if (r == 0) { 2487 ai = _yphostent(ypbuf, pai); 2488 if (ai) 2489 cur->ai_next = ai; 2490 free(ypbuf); 2491 } 2492 2493 if (sentinel.ai_next == NULL) { 2494 RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND); 2495 return NS_NOTFOUND; 2496 } 2497 *((struct addrinfo **)rv) = sentinel.ai_next; 2498 return NS_SUCCESS; 2499 } 2500 #endif 2501 2502 /* resolver logic */ 2503 2504 /* 2505 * Formulate a normal query, send, and await answer. 2506 * Returned answer is placed in supplied buffer "answer". 2507 * Perform preliminary check of answer, returning success only 2508 * if no error is indicated and the answer count is nonzero. 2509 * Return the size of the response on success, -1 on error. 2510 * Error number is left in h_errno. 2511 * 2512 * Caller must parse answer and determine whether it answers the question. 2513 */ 2514 static int 2515 res_queryN(const char *name, struct res_target *target, res_state res) 2516 { 2517 u_char *buf; 2518 HEADER *hp; 2519 int n; 2520 u_int oflags; 2521 struct res_target *t; 2522 int rcode; 2523 int ancount; 2524 2525 rcode = NOERROR; 2526 ancount = 0; 2527 2528 buf = malloc(MAXPACKET); 2529 if (!buf) { 2530 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2531 return -1; 2532 } 2533 2534 for (t = target; t; t = t->next) { 2535 int class, type; 2536 u_char *answer; 2537 int anslen; 2538 2539 hp = (HEADER *)(void *)t->answer; 2540 2541 /* make it easier... */ 2542 class = t->qclass; 2543 type = t->qtype; 2544 answer = t->answer; 2545 anslen = t->anslen; 2546 2547 oflags = res->_flags; 2548 2549 again: 2550 hp->rcode = NOERROR; /* default */ 2551 2552 #ifdef DEBUG 2553 if (res->options & RES_DEBUG) 2554 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2555 #endif 2556 2557 n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL, 2558 buf, MAXPACKET); 2559 if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 && 2560 (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U) 2561 n = res_nopt(res, n, buf, MAXPACKET, anslen); 2562 if (n <= 0) { 2563 #ifdef DEBUG 2564 if (res->options & RES_DEBUG) 2565 printf(";; res_query: mkquery failed\n"); 2566 #endif 2567 free(buf); 2568 RES_SET_H_ERRNO(res, NO_RECOVERY); 2569 return (n); 2570 } 2571 n = res_nsend(res, buf, n, answer, anslen); 2572 if (n < 0) { 2573 /* 2574 * if the query choked with EDNS0, retry 2575 * without EDNS0 2576 */ 2577 if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) 2578 != 0U && 2579 ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) { 2580 res->_flags |= RES_F_EDNS0ERR; 2581 if (res->options & RES_DEBUG) 2582 printf(";; res_nquery: retry without EDNS0\n"); 2583 goto again; 2584 } 2585 rcode = hp->rcode; /* record most recent error */ 2586 #ifdef DEBUG 2587 if (res->options & RES_DEBUG) 2588 printf(";; res_query: send error\n"); 2589 #endif 2590 continue; 2591 } 2592 2593 if (n > anslen) 2594 hp->rcode = FORMERR; /* XXX not very informative */ 2595 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2596 rcode = hp->rcode; /* record most recent error */ 2597 #ifdef DEBUG 2598 if (res->options & RES_DEBUG) 2599 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2600 ntohs(hp->ancount)); 2601 #endif 2602 continue; 2603 } 2604 2605 ancount += ntohs(hp->ancount); 2606 2607 t->n = n; 2608 } 2609 2610 free(buf); 2611 2612 if (ancount == 0) { 2613 switch (rcode) { 2614 case NXDOMAIN: 2615 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); 2616 break; 2617 case SERVFAIL: 2618 RES_SET_H_ERRNO(res, TRY_AGAIN); 2619 break; 2620 case NOERROR: 2621 RES_SET_H_ERRNO(res, NO_DATA); 2622 break; 2623 case FORMERR: 2624 case NOTIMP: 2625 case REFUSED: 2626 default: 2627 RES_SET_H_ERRNO(res, NO_RECOVERY); 2628 break; 2629 } 2630 return (-1); 2631 } 2632 return (ancount); 2633 } 2634 2635 /* 2636 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2637 * Return the size of the response on success, -1 on error. 2638 * If enabled, implement search rules until answer or unrecoverable failure 2639 * is detected. Error code, if any, is left in h_errno. 2640 */ 2641 static int 2642 res_searchN(const char *name, struct res_target *target, res_state res) 2643 { 2644 const char *cp, * const *domain; 2645 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2646 u_int dots; 2647 int trailing_dot, ret, saved_herrno; 2648 int got_nodata = 0, got_servfail = 0, root_on_list = 0; 2649 int tried_as_is = 0; 2650 int searched = 0; 2651 char abuf[MAXDNAME]; 2652 2653 errno = 0; 2654 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */ 2655 dots = 0; 2656 for (cp = name; *cp; cp++) 2657 dots += (*cp == '.'); 2658 trailing_dot = 0; 2659 if (cp > name && *--cp == '.') 2660 trailing_dot++; 2661 2662 /* 2663 * if there aren't any dots, it could be a user-level alias 2664 */ 2665 if (!dots && 2666 (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL) 2667 return (res_queryN(cp, target, res)); 2668 2669 /* 2670 * If there are enough dots in the name, let's just give it a 2671 * try 'as is'. The threshold can be set with the "ndots" option. 2672 * Also, query 'as is', if there is a trailing dot in the name. 2673 */ 2674 saved_herrno = -1; 2675 if (dots >= res->ndots || trailing_dot) { 2676 ret = res_querydomainN(name, NULL, target, res); 2677 if (ret > 0 || trailing_dot) 2678 return (ret); 2679 if (errno == ECONNREFUSED) { 2680 RES_SET_H_ERRNO(res, TRY_AGAIN); 2681 return (-1); 2682 } 2683 switch (res->res_h_errno) { 2684 case NO_DATA: 2685 case HOST_NOT_FOUND: 2686 break; 2687 case TRY_AGAIN: 2688 if (hp->rcode == SERVFAIL) 2689 break; 2690 /* FALLTHROUGH */ 2691 default: 2692 return (-1); 2693 } 2694 saved_herrno = res->res_h_errno; 2695 tried_as_is++; 2696 } 2697 2698 /* 2699 * We do at least one level of search if 2700 * - there is no dot and RES_DEFNAME is set, or 2701 * - there is at least one dot, there is no trailing dot, 2702 * and RES_DNSRCH is set. 2703 */ 2704 if ((!dots && (res->options & RES_DEFNAMES)) || 2705 (dots && !trailing_dot && (res->options & RES_DNSRCH))) { 2706 int done = 0; 2707 2708 for (domain = (const char * const *)res->dnsrch; 2709 *domain && !done; 2710 domain++) { 2711 searched = 1; 2712 2713 if (domain[0][0] == '\0' || 2714 (domain[0][0] == '.' && domain[0][1] == '\0')) 2715 root_on_list++; 2716 2717 if (root_on_list && tried_as_is) 2718 continue; 2719 2720 ret = res_querydomainN(name, *domain, target, res); 2721 if (ret > 0) 2722 return (ret); 2723 2724 /* 2725 * If no server present, give up. 2726 * If name isn't found in this domain, 2727 * keep trying higher domains in the search list 2728 * (if that's enabled). 2729 * On a NO_DATA error, keep trying, otherwise 2730 * a wildcard entry of another type could keep us 2731 * from finding this entry higher in the domain. 2732 * If we get some other error (negative answer or 2733 * server failure), then stop searching up, 2734 * but try the input name below in case it's 2735 * fully-qualified. 2736 */ 2737 if (errno == ECONNREFUSED) { 2738 RES_SET_H_ERRNO(res, TRY_AGAIN); 2739 return (-1); 2740 } 2741 2742 switch (res->res_h_errno) { 2743 case NO_DATA: 2744 got_nodata++; 2745 /* FALLTHROUGH */ 2746 case HOST_NOT_FOUND: 2747 /* keep trying */ 2748 break; 2749 case TRY_AGAIN: 2750 got_servfail++; 2751 if (hp->rcode == SERVFAIL) { 2752 /* try next search element, if any */ 2753 break; 2754 } 2755 /* FALLTHROUGH */ 2756 default: 2757 /* anything else implies that we're done */ 2758 done++; 2759 } 2760 /* 2761 * if we got here for some reason other than DNSRCH, 2762 * we only wanted one iteration of the loop, so stop. 2763 */ 2764 if (!(res->options & RES_DNSRCH)) 2765 done++; 2766 } 2767 } 2768 2769 switch (res->res_h_errno) { 2770 case NO_DATA: 2771 case HOST_NOT_FOUND: 2772 break; 2773 case TRY_AGAIN: 2774 if (hp->rcode == SERVFAIL) 2775 break; 2776 /* FALLTHROUGH */ 2777 default: 2778 goto giveup; 2779 } 2780 2781 /* 2782 * If the query has not already been tried as is then try it 2783 * unless RES_NOTLDQUERY is set and there were no dots. 2784 */ 2785 if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) && 2786 !(tried_as_is || root_on_list)) { 2787 ret = res_querydomainN(name, NULL, target, res); 2788 if (ret > 0) 2789 return (ret); 2790 } 2791 2792 /* 2793 * if we got here, we didn't satisfy the search. 2794 * if we did an initial full query, return that query's h_errno 2795 * (note that we wouldn't be here if that query had succeeded). 2796 * else if we ever got a nodata, send that back as the reason. 2797 * else send back meaningless h_errno, that being the one from 2798 * the last DNSRCH we did. 2799 */ 2800 giveup: 2801 if (saved_herrno != -1) 2802 RES_SET_H_ERRNO(res, saved_herrno); 2803 else if (got_nodata) 2804 RES_SET_H_ERRNO(res, NO_DATA); 2805 else if (got_servfail) 2806 RES_SET_H_ERRNO(res, TRY_AGAIN); 2807 return (-1); 2808 } 2809 2810 /* 2811 * Perform a call on res_query on the concatenation of name and domain, 2812 * removing a trailing dot from name if domain is NULL. 2813 */ 2814 static int 2815 res_querydomainN(const char *name, const char *domain, 2816 struct res_target *target, res_state res) 2817 { 2818 char nbuf[MAXDNAME]; 2819 const char *longname = nbuf; 2820 size_t n, d; 2821 2822 #ifdef DEBUG 2823 if (res->options & RES_DEBUG) 2824 printf(";; res_querydomain(%s, %s)\n", 2825 name, domain?domain:"<Nil>"); 2826 #endif 2827 if (domain == NULL) { 2828 /* 2829 * Check for trailing '.'; 2830 * copy without '.' if present. 2831 */ 2832 n = strlen(name); 2833 if (n >= MAXDNAME) { 2834 RES_SET_H_ERRNO(res, NO_RECOVERY); 2835 return (-1); 2836 } 2837 if (n > 0 && name[--n] == '.') { 2838 strncpy(nbuf, name, n); 2839 nbuf[n] = '\0'; 2840 } else 2841 longname = name; 2842 } else { 2843 n = strlen(name); 2844 d = strlen(domain); 2845 if (n + d + 1 >= MAXDNAME) { 2846 RES_SET_H_ERRNO(res, NO_RECOVERY); 2847 return (-1); 2848 } 2849 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2850 } 2851 return (res_queryN(longname, target, res)); 2852 } 2853