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 * "#ifdef FAITH" part is local hack for supporting IPv4-v6 translator. 34 * 35 * Issues to be discussed: 36 * - Return values. There are nonstandard return values defined and used 37 * in the source code. This is because RFC2553 is silent about which error 38 * code must be returned for which situation. 39 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 40 * invalid. current code - SEGV on freeaddrinfo(NULL) 41 * 42 * Note: 43 * - The code filters out AFs that are not supported by the kernel, 44 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 45 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 46 * in ai_flags? 47 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 48 * (1) what should we do against numeric hostname (2) what should we do 49 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 50 * non-loopback address configured? global address configured? 51 * 52 * OS specific notes for freebsd4: 53 * - FreeBSD supported $GAI. The code does not. 54 */ 55 56#include <sys/cdefs.h> 57__FBSDID("$FreeBSD$"); 58 59#include "namespace.h" 60#include <sys/types.h> 61#include <sys/param.h> 62#include <sys/socket.h> 63#include <net/if.h> 64#include <netinet/in.h> 65#include <net/if_types.h> 66#include <ifaddrs.h> 67#include <sys/queue.h> 68#ifdef INET6 69#include <net/if_var.h> 70#include <sys/sysctl.h> 71#include <sys/ioctl.h> 72#include <netinet6/in6_var.h> 73#include <netinet6/nd6.h> 74#endif 75#include <arpa/inet.h> 76#include <arpa/nameser.h> 77#include <rpc/rpc.h> 78#include <rpcsvc/yp_prot.h> 79#include <rpcsvc/ypclnt.h> 80#include <netdb.h> 81#include <resolv.h> 82#include <string.h> 83#include <stdlib.h> 84#include <stddef.h> 85#include <ctype.h> 86#include <unistd.h> 87#include <stdio.h> 88#include <errno.h> 89 90#include "res_config.h" 91 92#ifdef DEBUG 93#include <syslog.h> 94#endif 95 96#include <stdarg.h> 97#include <nsswitch.h> 98#include "un-namespace.h" 99#include "libc_private.h" 100#ifdef NS_CACHING 101#include "nscache.h" 102#endif 103 104#if defined(__KAME__) && defined(INET6) 105# define FAITH 106#endif 107 108#define ANY 0 109#define YES 1 110#define NO 0 111 112static const char in_addrany[] = { 0, 0, 0, 0 }; 113static const char in_loopback[] = { 127, 0, 0, 1 }; 114#ifdef INET6 115static const char in6_addrany[] = { 116 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 117}; 118static const char in6_loopback[] = { 119 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 120}; 121#endif 122 123struct policyqueue { 124 TAILQ_ENTRY(policyqueue) pc_entry; 125#ifdef INET6 126 struct in6_addrpolicy pc_policy; 127#endif 128}; 129TAILQ_HEAD(policyhead, policyqueue); 130 131static const struct afd { 132 int a_af; 133 int a_addrlen; 134 socklen_t a_socklen; 135 int a_off; 136 const char *a_addrany; 137 const char *a_loopback; 138 int a_scoped; 139} afdl [] = { 140#ifdef INET6 141#define N_INET6 0 142 {PF_INET6, sizeof(struct in6_addr), 143 sizeof(struct sockaddr_in6), 144 offsetof(struct sockaddr_in6, sin6_addr), 145 in6_addrany, in6_loopback, 1}, 146#define N_INET 1 147#else 148#define N_INET 0 149#endif 150 {PF_INET, sizeof(struct in_addr), 151 sizeof(struct sockaddr_in), 152 offsetof(struct sockaddr_in, sin_addr), 153 in_addrany, in_loopback, 0}, 154 {0, 0, 0, 0, NULL, NULL, 0}, 155}; 156 157struct explore { 158 int e_af; 159 int e_socktype; 160 int e_protocol; 161 int e_wild; 162#define WILD_AF(ex) ((ex)->e_wild & 0x01) 163#define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 164#define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 165}; 166 167static const struct explore explore[] = { 168#if 0 169 { PF_LOCAL, ANY, ANY, 0x01 }, 170#endif 171#ifdef INET6 172 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, 0x07 }, 173 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, 0x07 }, 174 { PF_INET6, SOCK_STREAM, IPPROTO_SCTP, 0x03 }, 175 { PF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 }, 176 { PF_INET6, SOCK_DGRAM, IPPROTO_UDPLITE, 0x03 }, 177 { PF_INET6, SOCK_RAW, ANY, 0x05 }, 178#endif 179 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, 0x07 }, 180 { PF_INET, SOCK_STREAM, IPPROTO_TCP, 0x07 }, 181 { PF_INET, SOCK_STREAM, IPPROTO_SCTP, 0x03 }, 182 { PF_INET, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 }, 183 { PF_INET, SOCK_DGRAM, IPPROTO_UDPLITE, 0x03 }, 184 { PF_INET, SOCK_RAW, ANY, 0x05 }, 185 { -1, 0, 0, 0 }, 186}; 187 188#ifdef INET6 189#define PTON_MAX 16 190#else 191#define PTON_MAX 4 192#endif 193 194#define AIO_SRCFLAG_DEPRECATED 0x1 195 196struct ai_order { 197 union { 198 struct sockaddr_storage aiou_ss; 199 struct sockaddr aiou_sa; 200 } aio_src_un; 201#define aio_srcsa aio_src_un.aiou_sa 202 u_int32_t aio_srcflag; 203 int aio_srcscope; 204 int aio_dstscope; 205 struct policyqueue *aio_srcpolicy; 206 struct policyqueue *aio_dstpolicy; 207 struct addrinfo *aio_ai; 208 int aio_matchlen; 209}; 210 211static const ns_src default_dns_files[] = { 212 { NSSRC_FILES, NS_SUCCESS }, 213 { NSSRC_DNS, NS_SUCCESS }, 214 { 0 } 215}; 216 217struct res_target { 218 struct res_target *next; 219 const char *name; /* domain name */ 220 int qclass, qtype; /* class and type of query */ 221 u_char *answer; /* buffer to put answer */ 222 int anslen; /* size of answer buffer */ 223 int n; /* result length */ 224}; 225 226#define MAXPACKET (64*1024) 227 228typedef union { 229 HEADER hdr; 230 u_char buf[MAXPACKET]; 231} querybuf; 232 233static int str2number(const char *, int *); 234static int explore_copy(const struct addrinfo *, const struct addrinfo *, 235 struct addrinfo **); 236static int explore_null(const struct addrinfo *, 237 const char *, struct addrinfo **); 238static int explore_numeric(const struct addrinfo *, const char *, 239 const char *, struct addrinfo **, const char *); 240static int explore_numeric_scope(const struct addrinfo *, const char *, 241 const char *, struct addrinfo **); 242static int get_canonname(const struct addrinfo *, 243 struct addrinfo *, const char *); 244static struct addrinfo *get_ai(const struct addrinfo *, 245 const struct afd *, const char *); 246static struct addrinfo *copy_ai(const struct addrinfo *); 247static int get_portmatch(const struct addrinfo *, const char *); 248static int get_port(struct addrinfo *, const char *, int); 249static const struct afd *find_afd(int); 250static int addrconfig(struct addrinfo *); 251#ifdef INET6 252static int is_ifdisabled(char *); 253#endif 254static void set_source(struct ai_order *, struct policyhead *); 255static int comp_dst(const void *, const void *); 256#ifdef INET6 257static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 258#endif 259static int gai_addr2scopetype(struct sockaddr *); 260 261static int explore_fqdn(const struct addrinfo *, const char *, 262 const char *, struct addrinfo **); 263 264static int reorder(struct addrinfo *); 265static int get_addrselectpolicy(struct policyhead *); 266static void free_addrselectpolicy(struct policyhead *); 267static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 268 struct policyhead *); 269static int matchlen(struct sockaddr *, struct sockaddr *); 270 271static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 272 const struct addrinfo *, res_state); 273#if defined(RESOLVSORT) 274static int addr4sort(struct addrinfo *, res_state); 275#endif 276static int _dns_getaddrinfo(void *, void *, va_list); 277static void _sethtent(FILE **); 278static void _endhtent(FILE **); 279static struct addrinfo *_gethtent(FILE **, const char *, 280 const struct addrinfo *); 281static int _files_getaddrinfo(void *, void *, va_list); 282#ifdef YP 283static struct addrinfo *_yphostent(char *, const struct addrinfo *); 284static int _yp_getaddrinfo(void *, void *, va_list); 285#endif 286#ifdef NS_CACHING 287static int addrinfo_id_func(char *, size_t *, va_list, void *); 288static int addrinfo_marshal_func(char *, size_t *, void *, va_list, void *); 289static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, void *); 290#endif 291 292static int res_queryN(const char *, struct res_target *, res_state); 293static int res_searchN(const char *, struct res_target *, res_state); 294static int res_querydomainN(const char *, const char *, 295 struct res_target *, res_state); 296 297/* XXX macros that make external reference is BAD. */ 298 299#define GET_AI(ai, afd, addr) \ 300do { \ 301 /* external reference: pai, error, and label free */ \ 302 (ai) = get_ai(pai, (afd), (addr)); \ 303 if ((ai) == NULL) { \ 304 error = EAI_MEMORY; \ 305 goto free; \ 306 } \ 307} while (/*CONSTCOND*/0) 308 309#define GET_PORT(ai, serv) \ 310do { \ 311 /* external reference: error and label free */ \ 312 error = get_port((ai), (serv), 0); \ 313 if (error != 0) \ 314 goto free; \ 315} while (/*CONSTCOND*/0) 316 317#define GET_CANONNAME(ai, str) \ 318do { \ 319 /* external reference: pai, error and label free */ \ 320 error = get_canonname(pai, (ai), (str)); \ 321 if (error != 0) \ 322 goto free; \ 323} while (/*CONSTCOND*/0) 324 325#define ERR(err) \ 326do { \ 327 /* external reference: error, and label bad */ \ 328 error = (err); \ 329 goto bad; \ 330 /*NOTREACHED*/ \ 331} while (/*CONSTCOND*/0) 332 333#define MATCH_FAMILY(x, y, w) \ 334 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 335#define MATCH(x, y, w) \ 336 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 337 338void 339freeaddrinfo(struct addrinfo *ai) 340{ 341 struct addrinfo *next; 342 343 do { 344 next = ai->ai_next; 345 if (ai->ai_canonname) 346 free(ai->ai_canonname); 347 /* no need to free(ai->ai_addr) */ 348 free(ai); 349 ai = next; 350 } while (ai); 351} 352 353static int 354str2number(const char *p, int *portp) 355{ 356 char *ep; 357 unsigned long v; 358 359 if (*p == '\0') 360 return -1; 361 ep = NULL; 362 errno = 0; 363 v = strtoul(p, &ep, 10); 364 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) { 365 *portp = v; 366 return 0; 367 } else 368 return -1; 369} 370 371int 372getaddrinfo(const char *hostname, const char *servname, 373 const struct addrinfo *hints, struct addrinfo **res) 374{ 375 struct addrinfo sentinel; 376 struct addrinfo *cur; 377 int error = 0; 378 struct addrinfo ai, ai0, *afai; 379 struct addrinfo *pai; 380 const struct afd *afd; 381 const struct explore *ex; 382 struct addrinfo *afailist[sizeof(afdl)/sizeof(afdl[0])]; 383 struct addrinfo *afai_unspec; 384 int found; 385 int numeric = 0; 386 387 /* ensure we return NULL on errors */ 388 *res = NULL; 389 390 memset(&ai, 0, sizeof(ai)); 391 392 memset(afailist, 0, sizeof(afailist)); 393 afai_unspec = NULL; 394 395 memset(&sentinel, 0, sizeof(sentinel)); 396 cur = &sentinel; 397 pai = &ai; 398 pai->ai_flags = 0; 399 pai->ai_family = PF_UNSPEC; 400 pai->ai_socktype = ANY; 401 pai->ai_protocol = ANY; 402 pai->ai_addrlen = 0; 403 pai->ai_canonname = NULL; 404 pai->ai_addr = NULL; 405 pai->ai_next = NULL; 406 407 if (hostname == NULL && servname == NULL) 408 return EAI_NONAME; 409 if (hints) { 410 /* error check for hints */ 411 if (hints->ai_addrlen || hints->ai_canonname || 412 hints->ai_addr || hints->ai_next) 413 ERR(EAI_BADHINTS); /* xxx */ 414 if (hints->ai_flags & ~AI_MASK) 415 ERR(EAI_BADFLAGS); 416 switch (hints->ai_family) { 417 case PF_UNSPEC: 418 case PF_INET: 419#ifdef INET6 420 case PF_INET6: 421#endif 422 break; 423 default: 424 ERR(EAI_FAMILY); 425 } 426 memcpy(pai, hints, sizeof(*pai)); 427 428 /* 429 * if both socktype/protocol are specified, check if they 430 * are meaningful combination. 431 */ 432 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 433 for (ex = explore; ex->e_af >= 0; ex++) { 434 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, 435 WILD_AF(ex))) 436 continue; 437 if (!MATCH(pai->ai_socktype, ex->e_socktype, 438 WILD_SOCKTYPE(ex))) 439 continue; 440 if (!MATCH(pai->ai_protocol, ex->e_protocol, 441 WILD_PROTOCOL(ex))) 442 continue; 443 444 /* matched */ 445 break; 446 } 447 448 if (ex->e_af < 0) 449 ERR(EAI_BADHINTS); 450 } 451 } 452 453 /* 454 * check for special cases. (1) numeric servname is disallowed if 455 * socktype/protocol are left unspecified. (2) servname is disallowed 456 * for raw and other inet{,6} sockets. 457 */ 458 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 459#ifdef PF_INET6 460 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 461#endif 462 ) { 463 ai0 = *pai; /* backup *pai */ 464 465 if (pai->ai_family == PF_UNSPEC) { 466#ifdef PF_INET6 467 pai->ai_family = PF_INET6; 468#else 469 pai->ai_family = PF_INET; 470#endif 471 } 472 error = get_portmatch(pai, servname); 473 if (error) 474 goto bad; 475 476 *pai = ai0; 477 } 478 479 ai0 = *pai; 480 481 /* 482 * NULL hostname, or numeric hostname. 483 * If numeric representation of AF1 can be interpreted as FQDN 484 * representation of AF2, we need to think again about the code below. 485 */ 486 found = 0; 487 for (afd = afdl; afd->a_af; afd++) { 488 *pai = ai0; 489 490 if (!MATCH_FAMILY(pai->ai_family, afd->a_af, 1)) 491 continue; 492 493 if (pai->ai_family == PF_UNSPEC) 494 pai->ai_family = afd->a_af; 495 496 if (hostname == NULL) { 497 error = explore_null(pai, servname, 498 &afailist[afd - afdl]); 499 500 /* 501 * Errors from explore_null should be unexpected and 502 * be caught to avoid returning an incomplete result. 503 */ 504 if (error != 0) 505 goto bad; 506 } else { 507 error = explore_numeric_scope(pai, hostname, servname, 508 &afailist[afd - afdl]); 509 510 /* 511 * explore_numeric_scope returns an error for address 512 * families that do not match that of hostname. 513 * Thus we should not catch the error at this moment. 514 */ 515 } 516 517 if (!error && afailist[afd - afdl]) 518 found++; 519 } 520 if (found) { 521 numeric = 1; 522 goto globcopy; 523 } 524 525 if (hostname == NULL) 526 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 527 if (pai->ai_flags & AI_NUMERICHOST) 528 ERR(EAI_NONAME); 529 530 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 531 ERR(EAI_FAIL); 532 533 /* 534 * hostname as alphabetical name. 535 */ 536 *pai = ai0; 537 error = explore_fqdn(pai, hostname, servname, &afai_unspec); 538 539globcopy: 540 for (ex = explore; ex->e_af >= 0; ex++) { 541 *pai = ai0; 542 543 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 544 continue; 545 if (!MATCH(pai->ai_socktype, ex->e_socktype, 546 WILD_SOCKTYPE(ex))) 547 continue; 548 if (!MATCH(pai->ai_protocol, ex->e_protocol, 549 WILD_PROTOCOL(ex))) 550 continue; 551 552 if (pai->ai_family == PF_UNSPEC) 553 pai->ai_family = ex->e_af; 554 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 555 pai->ai_socktype = ex->e_socktype; 556 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 557 pai->ai_protocol = ex->e_protocol; 558 559 /* 560 * if the servname does not match socktype/protocol, ignore it. 561 */ 562 if (get_portmatch(pai, servname) != 0) 563 continue; 564 565 if (afai_unspec) 566 afai = afai_unspec; 567 else { 568 if ((afd = find_afd(pai->ai_family)) == NULL) 569 continue; 570 /* XXX assumes that afd points inside afdl[] */ 571 afai = afailist[afd - afdl]; 572 } 573 if (!afai) 574 continue; 575 576 error = explore_copy(pai, afai, &cur->ai_next); 577 if (error != 0) 578 goto bad; 579 580 while (cur && cur->ai_next) 581 cur = cur->ai_next; 582 } 583 584 /* 585 * ensure we return either: 586 * - error == 0, non-NULL *res 587 * - error != 0, NULL *res 588 */ 589 if (error == 0) { 590 if (sentinel.ai_next) { 591 /* 592 * If the returned entry is for an active connection, 593 * and the given name is not numeric, reorder the 594 * list, so that the application would try the list 595 * in the most efficient order. Since the head entry 596 * of the original list may contain ai_canonname and 597 * that entry may be moved elsewhere in the new list, 598 * we keep the pointer and will restore it in the new 599 * head entry. (Note that RFC3493 requires the head 600 * entry store it when requested by the caller). 601 */ 602 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 603 if (!numeric) { 604 char *canonname; 605 606 canonname = 607 sentinel.ai_next->ai_canonname; 608 sentinel.ai_next->ai_canonname = NULL; 609 (void)reorder(&sentinel); 610 if (sentinel.ai_next->ai_canonname == 611 NULL) { 612 sentinel.ai_next->ai_canonname 613 = canonname; 614 } else if (canonname != NULL) 615 free(canonname); 616 } 617 } 618 *res = sentinel.ai_next; 619 } else 620 error = EAI_FAIL; 621 } 622 623bad: 624 if (afai_unspec) 625 freeaddrinfo(afai_unspec); 626 for (afd = afdl; afd->a_af; afd++) { 627 if (afailist[afd - afdl]) 628 freeaddrinfo(afailist[afd - afdl]); 629 } 630 if (!*res) 631 if (sentinel.ai_next) 632 freeaddrinfo(sentinel.ai_next); 633 634 return (error); 635} 636 637static int 638reorder(struct addrinfo *sentinel) 639{ 640 struct addrinfo *ai, **aip; 641 struct ai_order *aio; 642 int i, n; 643 struct policyhead policyhead; 644 645 /* count the number of addrinfo elements for sorting. */ 646 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 647 ; 648 649 /* 650 * If the number is small enough, we can skip the reordering process. 651 */ 652 if (n <= 1) 653 return(n); 654 655 /* allocate a temporary array for sort and initialization of it. */ 656 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 657 return(n); /* give up reordering */ 658 memset(aio, 0, sizeof(*aio) * n); 659 660 /* retrieve address selection policy from the kernel */ 661 TAILQ_INIT(&policyhead); 662 if (!get_addrselectpolicy(&policyhead)) { 663 /* no policy is installed into kernel, we don't sort. */ 664 free(aio); 665 return (n); 666 } 667 668 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 669 aio[i].aio_ai = ai; 670 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 671 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 672 &policyhead); 673 set_source(&aio[i], &policyhead); 674 } 675 676 /* perform sorting. */ 677 qsort(aio, n, sizeof(*aio), comp_dst); 678 679 /* reorder the addrinfo chain. */ 680 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 681 *aip = aio[i].aio_ai; 682 aip = &aio[i].aio_ai->ai_next; 683 } 684 *aip = NULL; 685 686 /* cleanup and return */ 687 free(aio); 688 free_addrselectpolicy(&policyhead); 689 return(n); 690} 691 692static int 693get_addrselectpolicy(struct policyhead *head) 694{ 695#ifdef INET6 696 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 697 size_t l; 698 char *buf; 699 struct in6_addrpolicy *pol, *ep; 700 701 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 702 return (0); 703 if (l == 0) 704 return (0); 705 if ((buf = malloc(l)) == NULL) 706 return (0); 707 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 708 free(buf); 709 return (0); 710 } 711 712 ep = (struct in6_addrpolicy *)(buf + l); 713 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 714 struct policyqueue *new; 715 716 if ((new = malloc(sizeof(*new))) == NULL) { 717 free_addrselectpolicy(head); /* make the list empty */ 718 break; 719 } 720 new->pc_policy = *pol; 721 TAILQ_INSERT_TAIL(head, new, pc_entry); 722 } 723 724 free(buf); 725 return (1); 726#else 727 return (0); 728#endif 729} 730 731static void 732free_addrselectpolicy(struct policyhead *head) 733{ 734 struct policyqueue *ent, *nent; 735 736 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 737 nent = TAILQ_NEXT(ent, pc_entry); 738 TAILQ_REMOVE(head, ent, pc_entry); 739 free(ent); 740 } 741} 742 743static struct policyqueue * 744match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 745{ 746#ifdef INET6 747 struct policyqueue *ent, *bestent = NULL; 748 struct in6_addrpolicy *pol; 749 int matchlen, bestmatchlen = -1; 750 u_char *mp, *ep, *k, *p, m; 751 struct sockaddr_in6 key; 752 753 switch(addr->sa_family) { 754 case AF_INET6: 755 key = *(struct sockaddr_in6 *)addr; 756 break; 757 case AF_INET: 758 /* convert the address into IPv4-mapped IPv6 address. */ 759 memset(&key, 0, sizeof(key)); 760 key.sin6_family = AF_INET6; 761 key.sin6_len = sizeof(key); 762 key.sin6_addr.s6_addr[10] = 0xff; 763 key.sin6_addr.s6_addr[11] = 0xff; 764 memcpy(&key.sin6_addr.s6_addr[12], 765 &((struct sockaddr_in *)addr)->sin_addr, 4); 766 break; 767 default: 768 return(NULL); 769 } 770 771 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 772 pol = &ent->pc_policy; 773 matchlen = 0; 774 775 mp = (u_char *)&pol->addrmask.sin6_addr; 776 ep = mp + 16; /* XXX: scope field? */ 777 k = (u_char *)&key.sin6_addr; 778 p = (u_char *)&pol->addr.sin6_addr; 779 for (; mp < ep && *mp; mp++, k++, p++) { 780 m = *mp; 781 if ((*k & m) != *p) 782 goto next; /* not match */ 783 if (m == 0xff) /* short cut for a typical case */ 784 matchlen += 8; 785 else { 786 while (m >= 0x80) { 787 matchlen++; 788 m <<= 1; 789 } 790 } 791 } 792 793 /* matched. check if this is better than the current best. */ 794 if (matchlen > bestmatchlen) { 795 bestent = ent; 796 bestmatchlen = matchlen; 797 } 798 799 next: 800 continue; 801 } 802 803 return(bestent); 804#else 805 return(NULL); 806#endif 807 808} 809 810static void 811set_source(struct ai_order *aio, struct policyhead *ph) 812{ 813 struct addrinfo ai = *aio->aio_ai; 814 struct sockaddr_storage ss; 815 socklen_t srclen; 816 int s; 817 818 /* set unspec ("no source is available"), just in case */ 819 aio->aio_srcsa.sa_family = AF_UNSPEC; 820 aio->aio_srcscope = -1; 821 822 switch(ai.ai_family) { 823 case AF_INET: 824#ifdef INET6 825 case AF_INET6: 826#endif 827 break; 828 default: /* ignore unsupported AFs explicitly */ 829 return; 830 } 831 832 /* XXX: make a dummy addrinfo to call connect() */ 833 ai.ai_socktype = SOCK_DGRAM; 834 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 835 ai.ai_next = NULL; 836 memset(&ss, 0, sizeof(ss)); 837 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 838 ai.ai_addr = (struct sockaddr *)&ss; 839 get_port(&ai, "1", 0); 840 841 /* open a socket to get the source address for the given dst */ 842 if ((s = _socket(ai.ai_family, ai.ai_socktype | SOCK_CLOEXEC, 843 ai.ai_protocol)) < 0) 844 return; /* give up */ 845 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 846 goto cleanup; 847 srclen = ai.ai_addrlen; 848 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 849 aio->aio_srcsa.sa_family = AF_UNSPEC; 850 goto cleanup; 851 } 852 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 853 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 854 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 855#ifdef INET6 856 if (ai.ai_family == AF_INET6) { 857 struct in6_ifreq ifr6; 858 u_int32_t flags6; 859 860 memset(&ifr6, 0, sizeof(ifr6)); 861 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 862 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 863 flags6 = ifr6.ifr_ifru.ifru_flags6; 864 if ((flags6 & IN6_IFF_DEPRECATED)) 865 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 866 } 867 } 868#endif 869 870 cleanup: 871 _close(s); 872 return; 873} 874 875static int 876matchlen(struct sockaddr *src, struct sockaddr *dst) 877{ 878 int match = 0; 879 u_char *s, *d; 880 u_char *lim, r; 881 int addrlen; 882 883 switch (src->sa_family) { 884#ifdef INET6 885 case AF_INET6: 886 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 887 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 888 addrlen = sizeof(struct in6_addr); 889 lim = s + addrlen; 890 break; 891#endif 892 case AF_INET: 893 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; 894 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; 895 addrlen = sizeof(struct in_addr); 896 lim = s + addrlen; 897 break; 898 default: 899 return(0); 900 } 901 902 while (s < lim) 903 if ((r = (*d++ ^ *s++)) != 0) { 904 while (r < addrlen * 8) { 905 match++; 906 r <<= 1; 907 } 908 break; 909 } else 910 match += 8; 911 return(match); 912} 913 914static int 915comp_dst(const void *arg1, const void *arg2) 916{ 917 const struct ai_order *dst1 = arg1, *dst2 = arg2; 918 919 /* 920 * Rule 1: Avoid unusable destinations. 921 * XXX: we currently do not consider if an appropriate route exists. 922 */ 923 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 924 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 925 return(-1); 926 } 927 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 928 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 929 return(1); 930 } 931 932 /* Rule 2: Prefer matching scope. */ 933 if (dst1->aio_dstscope == dst1->aio_srcscope && 934 dst2->aio_dstscope != dst2->aio_srcscope) { 935 return(-1); 936 } 937 if (dst1->aio_dstscope != dst1->aio_srcscope && 938 dst2->aio_dstscope == dst2->aio_srcscope) { 939 return(1); 940 } 941 942 /* Rule 3: Avoid deprecated addresses. */ 943 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 944 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 945 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 946 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 947 return(-1); 948 } 949 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 950 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 951 return(1); 952 } 953 } 954 955 /* Rule 4: Prefer home addresses. */ 956 /* XXX: not implemented yet */ 957 958 /* Rule 5: Prefer matching label. */ 959#ifdef INET6 960 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 961 dst1->aio_srcpolicy->pc_policy.label == 962 dst1->aio_dstpolicy->pc_policy.label && 963 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 964 dst2->aio_srcpolicy->pc_policy.label != 965 dst2->aio_dstpolicy->pc_policy.label)) { 966 return(-1); 967 } 968 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 969 dst2->aio_srcpolicy->pc_policy.label == 970 dst2->aio_dstpolicy->pc_policy.label && 971 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 972 dst1->aio_srcpolicy->pc_policy.label != 973 dst1->aio_dstpolicy->pc_policy.label)) { 974 return(1); 975 } 976#endif 977 978 /* Rule 6: Prefer higher precedence. */ 979#ifdef INET6 980 if (dst1->aio_dstpolicy && 981 (dst2->aio_dstpolicy == NULL || 982 dst1->aio_dstpolicy->pc_policy.preced > 983 dst2->aio_dstpolicy->pc_policy.preced)) { 984 return(-1); 985 } 986 if (dst2->aio_dstpolicy && 987 (dst1->aio_dstpolicy == NULL || 988 dst2->aio_dstpolicy->pc_policy.preced > 989 dst1->aio_dstpolicy->pc_policy.preced)) { 990 return(1); 991 } 992#endif 993 994 /* Rule 7: Prefer native transport. */ 995 /* XXX: not implemented yet */ 996 997 /* Rule 8: Prefer smaller scope. */ 998 if (dst1->aio_dstscope >= 0 && 999 dst1->aio_dstscope < dst2->aio_dstscope) { 1000 return(-1); 1001 } 1002 if (dst2->aio_dstscope >= 0 && 1003 dst2->aio_dstscope < dst1->aio_dstscope) { 1004 return(1); 1005 } 1006 1007 /* 1008 * Rule 9: Use longest matching prefix. 1009 * We compare the match length in a same AF only. 1010 */ 1011 if (dst1->aio_ai->ai_addr->sa_family == 1012 dst2->aio_ai->ai_addr->sa_family && 1013 dst1->aio_ai->ai_addr->sa_family != AF_INET) { 1014 if (dst1->aio_matchlen > dst2->aio_matchlen) { 1015 return(-1); 1016 } 1017 if (dst1->aio_matchlen < dst2->aio_matchlen) { 1018 return(1); 1019 } 1020 } 1021 1022 /* Rule 10: Otherwise, leave the order unchanged. */ 1023 return(-1); 1024} 1025 1026/* 1027 * Copy from scope.c. 1028 * XXX: we should standardize the functions and link them as standard 1029 * library. 1030 */ 1031static int 1032gai_addr2scopetype(struct sockaddr *sa) 1033{ 1034#ifdef INET6 1035 struct sockaddr_in6 *sa6; 1036#endif 1037 struct sockaddr_in *sa4; 1038 1039 switch(sa->sa_family) { 1040#ifdef INET6 1041 case AF_INET6: 1042 sa6 = (struct sockaddr_in6 *)sa; 1043 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1044 /* just use the scope field of the multicast address */ 1045 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1046 } 1047 /* 1048 * Unicast addresses: map scope type to corresponding scope 1049 * value defined for multcast addresses. 1050 * XXX: hardcoded scope type values are bad... 1051 */ 1052 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1053 return(1); /* node local scope */ 1054 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1055 return(2); /* link-local scope */ 1056 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1057 return(5); /* site-local scope */ 1058 return(14); /* global scope */ 1059 break; 1060#endif 1061 case AF_INET: 1062 /* 1063 * IPv4 pseudo scoping according to RFC 3484. 1064 */ 1065 sa4 = (struct sockaddr_in *)sa; 1066 /* IPv4 autoconfiguration addresses have link-local scope. */ 1067 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1068 ((u_char *)&sa4->sin_addr)[1] == 254) 1069 return(2); 1070 /* Private addresses have site-local scope. */ 1071 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1072 (((u_char *)&sa4->sin_addr)[0] == 172 && 1073 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1074 (((u_char *)&sa4->sin_addr)[0] == 192 && 1075 ((u_char *)&sa4->sin_addr)[1] == 168)) 1076 return(14); /* XXX: It should be 5 unless NAT */ 1077 /* Loopback addresses have link-local scope. */ 1078 if (((u_char *)&sa4->sin_addr)[0] == 127) 1079 return(2); 1080 return(14); 1081 break; 1082 default: 1083 errno = EAFNOSUPPORT; /* is this a good error? */ 1084 return(-1); 1085 } 1086} 1087 1088static int 1089explore_copy(const struct addrinfo *pai, const struct addrinfo *src0, 1090 struct addrinfo **res) 1091{ 1092 int error; 1093 struct addrinfo sentinel, *cur; 1094 const struct addrinfo *src; 1095 1096 error = 0; 1097 sentinel.ai_next = NULL; 1098 cur = &sentinel; 1099 1100 for (src = src0; src != NULL; src = src->ai_next) { 1101 if (src->ai_family != pai->ai_family) 1102 continue; 1103 1104 cur->ai_next = copy_ai(src); 1105 if (!cur->ai_next) { 1106 error = EAI_MEMORY; 1107 goto fail; 1108 } 1109 1110 cur->ai_next->ai_socktype = pai->ai_socktype; 1111 cur->ai_next->ai_protocol = pai->ai_protocol; 1112 cur = cur->ai_next; 1113 } 1114 1115 *res = sentinel.ai_next; 1116 return 0; 1117 1118fail: 1119 freeaddrinfo(sentinel.ai_next); 1120 return error; 1121} 1122 1123/* 1124 * hostname == NULL. 1125 * passive socket -> anyaddr (0.0.0.0 or ::) 1126 * non-passive socket -> localhost (127.0.0.1 or ::1) 1127 */ 1128static int 1129explore_null(const struct addrinfo *pai, const char *servname, 1130 struct addrinfo **res) 1131{ 1132 int s; 1133 const struct afd *afd; 1134 struct addrinfo *ai; 1135 int error; 1136 1137 *res = NULL; 1138 ai = NULL; 1139 1140 /* 1141 * filter out AFs that are not supported by the kernel 1142 * XXX errno? 1143 */ 1144 s = _socket(pai->ai_family, SOCK_DGRAM | SOCK_CLOEXEC, 0); 1145 if (s < 0) { 1146 if (errno != EMFILE) 1147 return 0; 1148 } else 1149 _close(s); 1150 1151 afd = find_afd(pai->ai_family); 1152 if (afd == NULL) 1153 return 0; 1154 1155 if (pai->ai_flags & AI_PASSIVE) { 1156 GET_AI(ai, afd, afd->a_addrany); 1157 GET_PORT(ai, servname); 1158 } else { 1159 GET_AI(ai, afd, afd->a_loopback); 1160 GET_PORT(ai, servname); 1161 } 1162 1163 *res = ai; 1164 return 0; 1165 1166free: 1167 if (ai != NULL) 1168 freeaddrinfo(ai); 1169 return error; 1170} 1171 1172/* 1173 * numeric hostname 1174 */ 1175static int 1176explore_numeric(const struct addrinfo *pai, const char *hostname, 1177 const char *servname, struct addrinfo **res, const char *canonname) 1178{ 1179 const struct afd *afd; 1180 struct addrinfo *ai; 1181 int error; 1182 char pton[PTON_MAX]; 1183 1184 *res = NULL; 1185 ai = NULL; 1186 1187 afd = find_afd(pai->ai_family); 1188 if (afd == NULL) 1189 return 0; 1190 1191 switch (afd->a_af) { 1192 case AF_INET: 1193 /* 1194 * RFC3493 requires getaddrinfo() to accept AF_INET formats 1195 * that are accepted by inet_addr() and its family. The 1196 * accepted forms includes the "classful" one, which inet_pton 1197 * does not accept. So we need to separate the case for 1198 * AF_INET. 1199 */ 1200 if (inet_aton(hostname, (struct in_addr *)pton) != 1) 1201 return 0; 1202 break; 1203 default: 1204 if (inet_pton(afd->a_af, hostname, pton) != 1) 1205 return 0; 1206 break; 1207 } 1208 1209 if (pai->ai_family == afd->a_af) { 1210 GET_AI(ai, afd, pton); 1211 GET_PORT(ai, servname); 1212 if ((pai->ai_flags & AI_CANONNAME)) { 1213 /* 1214 * Set the numeric address itself as the canonical 1215 * name, based on a clarification in RFC3493. 1216 */ 1217 GET_CANONNAME(ai, canonname); 1218 } 1219 } else { 1220 /* 1221 * XXX: This should not happen since we already matched the AF 1222 * by find_afd. 1223 */ 1224 ERR(EAI_FAMILY); 1225 } 1226 1227 *res = ai; 1228 return 0; 1229 1230free: 1231bad: 1232 if (ai != NULL) 1233 freeaddrinfo(ai); 1234 return error; 1235} 1236 1237/* 1238 * numeric hostname with scope 1239 */ 1240static int 1241explore_numeric_scope(const struct addrinfo *pai, const char *hostname, 1242 const char *servname, struct addrinfo **res) 1243{ 1244#if !defined(SCOPE_DELIMITER) || !defined(INET6) 1245 return explore_numeric(pai, hostname, servname, res, hostname); 1246#else 1247 const struct afd *afd; 1248 struct addrinfo *cur; 1249 int error; 1250 char *cp, *hostname2 = NULL, *scope, *addr; 1251 struct sockaddr_in6 *sin6; 1252 1253 afd = find_afd(pai->ai_family); 1254 if (afd == NULL) 1255 return 0; 1256 1257 if (!afd->a_scoped) 1258 return explore_numeric(pai, hostname, servname, res, hostname); 1259 1260 cp = strchr(hostname, SCOPE_DELIMITER); 1261 if (cp == NULL) 1262 return explore_numeric(pai, hostname, servname, res, hostname); 1263 1264 /* 1265 * Handle special case of <scoped_address><delimiter><scope id> 1266 */ 1267 hostname2 = strdup(hostname); 1268 if (hostname2 == NULL) 1269 return EAI_MEMORY; 1270 /* terminate at the delimiter */ 1271 hostname2[cp - hostname] = '\0'; 1272 addr = hostname2; 1273 scope = cp + 1; 1274 1275 error = explore_numeric(pai, addr, servname, res, hostname); 1276 if (error == 0) { 1277 u_int32_t scopeid; 1278 1279 for (cur = *res; cur; cur = cur->ai_next) { 1280 if (cur->ai_family != AF_INET6) 1281 continue; 1282 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1283 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1284 free(hostname2); 1285 freeaddrinfo(*res); 1286 *res = NULL; 1287 return(EAI_NONAME); /* XXX: is return OK? */ 1288 } 1289 sin6->sin6_scope_id = scopeid; 1290 } 1291 } 1292 1293 free(hostname2); 1294 1295 if (error && *res) { 1296 freeaddrinfo(*res); 1297 *res = NULL; 1298 } 1299 return error; 1300#endif 1301} 1302 1303static int 1304get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) 1305{ 1306 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1307 ai->ai_canonname = strdup(str); 1308 if (ai->ai_canonname == NULL) 1309 return EAI_MEMORY; 1310 } 1311 return 0; 1312} 1313 1314static struct addrinfo * 1315get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) 1316{ 1317 char *p; 1318 struct addrinfo *ai; 1319#ifdef FAITH 1320 struct in6_addr faith_prefix; 1321 char *fp_str; 1322 int translate = 0; 1323#endif 1324 1325#ifdef FAITH 1326 /* 1327 * Transfrom an IPv4 addr into a special IPv6 addr format for 1328 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1329 * 1330 * +-----------------------------------+------------+ 1331 * | faith prefix part (12 bytes) | embedded | 1332 * | | IPv4 addr part (4 bytes) 1333 * +-----------------------------------+------------+ 1334 * 1335 * faith prefix part is specified as ascii IPv6 addr format 1336 * in environmental variable GAI. 1337 * For FAITH to work correctly, routing to faith prefix must be 1338 * setup toward a machine where a FAITH daemon operates. 1339 * Also, the machine must enable some mechanizm 1340 * (e.g. faith interface hack) to divert those packet with 1341 * faith prefixed destination addr to user-land FAITH daemon. 1342 */ 1343 fp_str = getenv("GAI"); 1344 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1345 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1346 u_int32_t v4a; 1347 u_int8_t v4a_top; 1348 1349 memcpy(&v4a, addr, sizeof v4a); 1350 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1351 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1352 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1353 afd = &afdl[N_INET6]; 1354 memcpy(&faith_prefix.s6_addr[12], addr, 1355 sizeof(struct in_addr)); 1356 translate = 1; 1357 } 1358 } 1359#endif 1360 1361 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1362 + (afd->a_socklen)); 1363 if (ai == NULL) 1364 return NULL; 1365 1366 memcpy(ai, pai, sizeof(struct addrinfo)); 1367 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1368 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1369 ai->ai_addr->sa_len = afd->a_socklen; 1370 ai->ai_addrlen = afd->a_socklen; 1371 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1372 p = (char *)(void *)(ai->ai_addr); 1373#ifdef FAITH 1374 if (translate == 1) 1375 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1376 else 1377#endif 1378 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1379 return ai; 1380} 1381 1382/* XXX need to malloc() the same way we do from other functions! */ 1383static struct addrinfo * 1384copy_ai(const struct addrinfo *pai) 1385{ 1386 struct addrinfo *ai; 1387 size_t l; 1388 1389 l = sizeof(*ai) + pai->ai_addrlen; 1390 if ((ai = (struct addrinfo *)malloc(l)) == NULL) 1391 return NULL; 1392 memset(ai, 0, l); 1393 memcpy(ai, pai, sizeof(*ai)); 1394 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1395 memcpy(ai->ai_addr, pai->ai_addr, pai->ai_addrlen); 1396 1397 if (pai->ai_canonname) { 1398 l = strlen(pai->ai_canonname) + 1; 1399 if ((ai->ai_canonname = malloc(l)) == NULL) { 1400 free(ai); 1401 return NULL; 1402 } 1403 strlcpy(ai->ai_canonname, pai->ai_canonname, l); 1404 } else { 1405 /* just to make sure */ 1406 ai->ai_canonname = NULL; 1407 } 1408 1409 ai->ai_next = NULL; 1410 1411 return ai; 1412} 1413 1414static int 1415get_portmatch(const struct addrinfo *ai, const char *servname) 1416{ 1417 1418 /* get_port does not touch first argument when matchonly == 1. */ 1419 /* LINTED const cast */ 1420 return get_port((struct addrinfo *)ai, servname, 1); 1421} 1422 1423static int 1424get_port(struct addrinfo *ai, const char *servname, int matchonly) 1425{ 1426 const char *proto; 1427 struct servent *sp; 1428 int port, error; 1429 int allownumeric; 1430 1431 if (servname == NULL) 1432 return 0; 1433 switch (ai->ai_family) { 1434 case AF_INET: 1435#ifdef AF_INET6 1436 case AF_INET6: 1437#endif 1438 break; 1439 default: 1440 return 0; 1441 } 1442 1443 switch (ai->ai_socktype) { 1444 case SOCK_RAW: 1445 return EAI_SERVICE; 1446 case SOCK_DGRAM: 1447 case SOCK_STREAM: 1448 case SOCK_SEQPACKET: 1449 allownumeric = 1; 1450 break; 1451 case ANY: 1452 switch (ai->ai_family) { 1453 case AF_INET: 1454#ifdef AF_INET6 1455 case AF_INET6: 1456#endif 1457 allownumeric = 1; 1458 break; 1459 default: 1460 allownumeric = 0; 1461 break; 1462 } 1463 break; 1464 default: 1465 return EAI_SOCKTYPE; 1466 } 1467 1468 error = str2number(servname, &port); 1469 if (error == 0) { 1470 if (!allownumeric) 1471 return EAI_SERVICE; 1472 if (port < 0 || port > 65535) 1473 return EAI_SERVICE; 1474 port = htons(port); 1475 } else { 1476 if (ai->ai_flags & AI_NUMERICSERV) 1477 return EAI_NONAME; 1478 1479 switch (ai->ai_protocol) { 1480 case IPPROTO_UDP: 1481 proto = "udp"; 1482 break; 1483 case IPPROTO_TCP: 1484 proto = "tcp"; 1485 break; 1486 case IPPROTO_SCTP: 1487 proto = "sctp"; 1488 break; 1489 case IPPROTO_UDPLITE: 1490 proto = "udplite"; 1491 break; 1492 default: 1493 proto = NULL; 1494 break; 1495 } 1496 1497 if ((sp = getservbyname(servname, proto)) == NULL) 1498 return EAI_SERVICE; 1499 port = sp->s_port; 1500 } 1501 1502 if (!matchonly) { 1503 switch (ai->ai_family) { 1504 case AF_INET: 1505 ((struct sockaddr_in *)(void *) 1506 ai->ai_addr)->sin_port = port; 1507 break; 1508#ifdef INET6 1509 case AF_INET6: 1510 ((struct sockaddr_in6 *)(void *) 1511 ai->ai_addr)->sin6_port = port; 1512 break; 1513#endif 1514 } 1515 } 1516 1517 return 0; 1518} 1519 1520static const struct afd * 1521find_afd(int af) 1522{ 1523 const struct afd *afd; 1524 1525 if (af == PF_UNSPEC) 1526 return NULL; 1527 for (afd = afdl; afd->a_af; afd++) { 1528 if (afd->a_af == af) 1529 return afd; 1530 } 1531 return NULL; 1532} 1533 1534/* 1535 * RFC 3493: AI_ADDRCONFIG check. Determines which address families are 1536 * configured on the local system and correlates with pai->ai_family value. 1537 * If an address family is not configured on the system, it will not be 1538 * queried for. For this purpose, loopback addresses are not considered 1539 * configured addresses. 1540 * 1541 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1542 * _dns_getaddrinfo. 1543 */ 1544static int 1545addrconfig(struct addrinfo *pai) 1546{ 1547 struct ifaddrs *ifaddrs, *ifa; 1548 struct sockaddr_in *sin; 1549#ifdef INET6 1550 struct sockaddr_in6 *sin6; 1551#endif 1552 int seen_inet = 0, seen_inet6 = 0; 1553 1554 if (getifaddrs(&ifaddrs) != 0) 1555 return (0); 1556 1557 for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) { 1558 if (ifa->ifa_addr == NULL || (ifa->ifa_flags & IFF_UP) == 0) 1559 continue; 1560 switch (ifa->ifa_addr->sa_family) { 1561 case AF_INET: 1562 if (seen_inet) 1563 continue; 1564 sin = (struct sockaddr_in *)(ifa->ifa_addr); 1565 if (IN_LOOPBACK(htonl(sin->sin_addr.s_addr))) 1566 continue; 1567 seen_inet = 1; 1568 break; 1569#ifdef INET6 1570 case AF_INET6: 1571 if (seen_inet6) 1572 continue; 1573 sin6 = (struct sockaddr_in6 *)(ifa->ifa_addr); 1574 if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr)) 1575 continue; 1576 if ((ifa->ifa_flags & IFT_LOOP) != 0 && 1577 IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) 1578 continue; 1579 if (is_ifdisabled(ifa->ifa_name)) 1580 continue; 1581 seen_inet6 = 1; 1582 break; 1583#endif 1584 } 1585 } 1586 freeifaddrs(ifaddrs); 1587 1588 switch(pai->ai_family) { 1589 case AF_INET6: 1590 return (seen_inet6); 1591 case AF_INET: 1592 return (seen_inet); 1593 case AF_UNSPEC: 1594 if (seen_inet == seen_inet6) 1595 return (seen_inet); 1596 pai->ai_family = seen_inet ? AF_INET : AF_INET6; 1597 return (1); 1598 } 1599 return (1); 1600} 1601 1602#ifdef INET6 1603static int 1604is_ifdisabled(char *name) 1605{ 1606 struct in6_ndireq nd; 1607 int fd; 1608 1609 if ((fd = _socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, 0)) < 0) 1610 return (-1); 1611 memset(&nd, 0, sizeof(nd)); 1612 strlcpy(nd.ifname, name, sizeof(nd.ifname)); 1613 if (_ioctl(fd, SIOCGIFINFO_IN6, &nd) < 0) { 1614 _close(fd); 1615 return (-1); 1616 } 1617 _close(fd); 1618 return ((nd.ndi.flags & ND6_IFF_IFDISABLED) != 0); 1619} 1620 1621/* convert a string to a scope identifier. XXX: IPv6 specific */ 1622static int 1623ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid) 1624{ 1625 u_long lscopeid; 1626 struct in6_addr *a6; 1627 char *ep; 1628 1629 a6 = &sin6->sin6_addr; 1630 1631 /* empty scopeid portion is invalid */ 1632 if (*scope == '\0') 1633 return -1; 1634 1635 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6) || 1636 IN6_IS_ADDR_MC_NODELOCAL(a6)) { 1637 /* 1638 * We currently assume a one-to-one mapping between links 1639 * and interfaces, so we simply use interface indices for 1640 * like-local scopes. 1641 */ 1642 *scopeid = if_nametoindex(scope); 1643 if (*scopeid == 0) 1644 goto trynumeric; 1645 return 0; 1646 } 1647 1648 /* still unclear about literal, allow numeric only - placeholder */ 1649 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1650 goto trynumeric; 1651 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1652 goto trynumeric; 1653 else 1654 goto trynumeric; /* global */ 1655 1656 /* try to convert to a numeric id as a last resort */ 1657 trynumeric: 1658 errno = 0; 1659 lscopeid = strtoul(scope, &ep, 10); 1660 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1661 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1662 return 0; 1663 else 1664 return -1; 1665} 1666#endif 1667 1668 1669#ifdef NS_CACHING 1670static int 1671addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap, 1672 void *cache_mdata) 1673{ 1674 res_state statp; 1675 u_long res_options; 1676 1677 const int op_id = 0; /* identifies the getaddrinfo for the cache */ 1678 char *hostname; 1679 struct addrinfo *hints; 1680 1681 char *p; 1682 int ai_flags, ai_family, ai_socktype, ai_protocol; 1683 size_t desired_size, size; 1684 1685 statp = __res_state(); 1686 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES | 1687 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6); 1688 1689 hostname = va_arg(ap, char *); 1690 hints = va_arg(ap, struct addrinfo *); 1691 1692 desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4; 1693 if (hostname != NULL) { 1694 size = strlen(hostname); 1695 desired_size += size + 1; 1696 } else 1697 size = 0; 1698 1699 if (desired_size > *buffer_size) { 1700 *buffer_size = desired_size; 1701 return (NS_RETURN); 1702 } 1703 1704 if (hints == NULL) 1705 ai_flags = ai_family = ai_socktype = ai_protocol = 0; 1706 else { 1707 ai_flags = hints->ai_flags; 1708 ai_family = hints->ai_family; 1709 ai_socktype = hints->ai_socktype; 1710 ai_protocol = hints->ai_protocol; 1711 } 1712 1713 p = buffer; 1714 memcpy(p, &res_options, sizeof(res_options)); 1715 p += sizeof(res_options); 1716 1717 memcpy(p, &op_id, sizeof(int)); 1718 p += sizeof(int); 1719 1720 memcpy(p, &ai_flags, sizeof(int)); 1721 p += sizeof(int); 1722 1723 memcpy(p, &ai_family, sizeof(int)); 1724 p += sizeof(int); 1725 1726 memcpy(p, &ai_socktype, sizeof(int)); 1727 p += sizeof(int); 1728 1729 memcpy(p, &ai_protocol, sizeof(int)); 1730 p += sizeof(int); 1731 1732 if (hostname != NULL) 1733 memcpy(p, hostname, size); 1734 1735 *buffer_size = desired_size; 1736 return (NS_SUCCESS); 1737} 1738 1739static int 1740addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval, 1741 va_list ap, void *cache_mdata) 1742{ 1743 struct addrinfo *ai, *cai; 1744 char *p; 1745 size_t desired_size, size, ai_size; 1746 1747 ai = *((struct addrinfo **)retval); 1748 1749 desired_size = sizeof(size_t); 1750 ai_size = 0; 1751 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1752 desired_size += sizeof(struct addrinfo) + cai->ai_addrlen; 1753 if (cai->ai_canonname != NULL) 1754 desired_size += sizeof(size_t) + 1755 strlen(cai->ai_canonname); 1756 ++ai_size; 1757 } 1758 1759 if (desired_size > *buffer_size) { 1760 /* this assignment is here for future use */ 1761 errno = ERANGE; 1762 *buffer_size = desired_size; 1763 return (NS_RETURN); 1764 } 1765 1766 memset(buffer, 0, desired_size); 1767 p = buffer; 1768 1769 memcpy(p, &ai_size, sizeof(size_t)); 1770 p += sizeof(size_t); 1771 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1772 memcpy(p, cai, sizeof(struct addrinfo)); 1773 p += sizeof(struct addrinfo); 1774 1775 memcpy(p, cai->ai_addr, cai->ai_addrlen); 1776 p += cai->ai_addrlen; 1777 1778 if (cai->ai_canonname != NULL) { 1779 size = strlen(cai->ai_canonname); 1780 memcpy(p, &size, sizeof(size_t)); 1781 p += sizeof(size_t); 1782 1783 memcpy(p, cai->ai_canonname, size); 1784 p += size; 1785 } 1786 } 1787 1788 return (NS_SUCCESS); 1789} 1790 1791static int 1792addrinfo_unmarshal_func(char *buffer, size_t buffer_size, void *retval, 1793 va_list ap, void *cache_mdata) 1794{ 1795 struct addrinfo new_ai, *result, *sentinel, *lasts; 1796 1797 char *p; 1798 size_t ai_size, ai_i, size; 1799 1800 p = buffer; 1801 memcpy(&ai_size, p, sizeof(size_t)); 1802 p += sizeof(size_t); 1803 1804 result = NULL; 1805 lasts = NULL; 1806 for (ai_i = 0; ai_i < ai_size; ++ai_i) { 1807 memcpy(&new_ai, p, sizeof(struct addrinfo)); 1808 p += sizeof(struct addrinfo); 1809 size = new_ai.ai_addrlen + sizeof(struct addrinfo) + 1810 _ALIGNBYTES; 1811 1812 sentinel = (struct addrinfo *)malloc(size); 1813 memset(sentinel, 0, size); 1814 1815 memcpy(sentinel, &new_ai, sizeof(struct addrinfo)); 1816 sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel + 1817 sizeof(struct addrinfo)); 1818 1819 memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen); 1820 p += new_ai.ai_addrlen; 1821 1822 if (new_ai.ai_canonname != NULL) { 1823 memcpy(&size, p, sizeof(size_t)); 1824 p += sizeof(size_t); 1825 1826 sentinel->ai_canonname = (char *)malloc(size + 1); 1827 memset(sentinel->ai_canonname, 0, size + 1); 1828 1829 memcpy(sentinel->ai_canonname, p, size); 1830 p += size; 1831 } 1832 1833 if (result == NULL) { 1834 result = sentinel; 1835 lasts = sentinel; 1836 } else { 1837 lasts->ai_next = sentinel; 1838 lasts = sentinel; 1839 } 1840 } 1841 1842 *((struct addrinfo **)retval) = result; 1843 return (NS_SUCCESS); 1844} 1845#endif /* NS_CACHING */ 1846 1847/* 1848 * FQDN hostname, DNS lookup 1849 */ 1850static int 1851explore_fqdn(const struct addrinfo *pai, const char *hostname, 1852 const char *servname, struct addrinfo **res) 1853{ 1854 struct addrinfo *result; 1855 struct addrinfo *cur; 1856 int error = 0; 1857 1858#ifdef NS_CACHING 1859 static const nss_cache_info cache_info = 1860 NS_COMMON_CACHE_INFO_INITIALIZER( 1861 hosts, NULL, addrinfo_id_func, addrinfo_marshal_func, 1862 addrinfo_unmarshal_func); 1863#endif 1864 static const ns_dtab dtab[] = { 1865 NS_FILES_CB(_files_getaddrinfo, NULL) 1866 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1867 NS_NIS_CB(_yp_getaddrinfo, NULL) 1868#ifdef NS_CACHING 1869 NS_CACHE_CB(&cache_info) 1870#endif 1871 { 0 } 1872 }; 1873 1874 result = NULL; 1875 1876 /* 1877 * if the servname does not match socktype/protocol, ignore it. 1878 */ 1879 if (get_portmatch(pai, servname) != 0) 1880 return 0; 1881 1882 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1883 default_dns_files, hostname, pai)) { 1884 case NS_TRYAGAIN: 1885 error = EAI_AGAIN; 1886 goto free; 1887 case NS_UNAVAIL: 1888 error = EAI_FAIL; 1889 goto free; 1890 case NS_NOTFOUND: 1891 error = EAI_NONAME; 1892 goto free; 1893 case NS_SUCCESS: 1894 error = 0; 1895 for (cur = result; cur; cur = cur->ai_next) { 1896 GET_PORT(cur, servname); 1897 /* canonname should be filled already */ 1898 } 1899 break; 1900 } 1901 1902 *res = result; 1903 1904 return 0; 1905 1906free: 1907 if (result) 1908 freeaddrinfo(result); 1909 return error; 1910} 1911 1912#ifdef DEBUG 1913static const char AskedForGot[] = 1914 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1915#endif 1916 1917static struct addrinfo * 1918getanswer(const querybuf *answer, int anslen, const char *qname, int qtype, 1919 const struct addrinfo *pai, res_state res) 1920{ 1921 struct addrinfo sentinel, *cur; 1922 struct addrinfo ai; 1923 const struct afd *afd; 1924 char *canonname; 1925 const HEADER *hp; 1926 const u_char *cp; 1927 int n; 1928 const u_char *eom; 1929 char *bp, *ep; 1930 int type, class, ancount, qdcount; 1931 int haveanswer, had_error; 1932 char tbuf[MAXDNAME]; 1933 int (*name_ok)(const char *); 1934 char hostbuf[8*1024]; 1935 1936 memset(&sentinel, 0, sizeof(sentinel)); 1937 cur = &sentinel; 1938 1939 canonname = NULL; 1940 eom = answer->buf + anslen; 1941 switch (qtype) { 1942 case T_A: 1943 case T_AAAA: 1944 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1945 name_ok = res_hnok; 1946 break; 1947 default: 1948 return (NULL); /* XXX should be abort(); */ 1949 } 1950 /* 1951 * find first satisfactory answer 1952 */ 1953 hp = &answer->hdr; 1954 ancount = ntohs(hp->ancount); 1955 qdcount = ntohs(hp->qdcount); 1956 bp = hostbuf; 1957 ep = hostbuf + sizeof hostbuf; 1958 cp = answer->buf + HFIXEDSZ; 1959 if (qdcount != 1) { 1960 RES_SET_H_ERRNO(res, NO_RECOVERY); 1961 return (NULL); 1962 } 1963 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1964 if ((n < 0) || !(*name_ok)(bp)) { 1965 RES_SET_H_ERRNO(res, NO_RECOVERY); 1966 return (NULL); 1967 } 1968 cp += n + QFIXEDSZ; 1969 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1970 /* res_send() has already verified that the query name is the 1971 * same as the one we sent; this just gets the expanded name 1972 * (i.e., with the succeeding search-domain tacked on). 1973 */ 1974 n = strlen(bp) + 1; /* for the \0 */ 1975 if (n >= MAXHOSTNAMELEN) { 1976 RES_SET_H_ERRNO(res, NO_RECOVERY); 1977 return (NULL); 1978 } 1979 canonname = bp; 1980 bp += n; 1981 /* The qname can be abbreviated, but h_name is now absolute. */ 1982 qname = canonname; 1983 } 1984 haveanswer = 0; 1985 had_error = 0; 1986 while (ancount-- > 0 && cp < eom && !had_error) { 1987 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1988 if ((n < 0) || !(*name_ok)(bp)) { 1989 had_error++; 1990 continue; 1991 } 1992 cp += n; /* name */ 1993 type = _getshort(cp); 1994 cp += INT16SZ; /* type */ 1995 class = _getshort(cp); 1996 cp += INT16SZ + INT32SZ; /* class, TTL */ 1997 n = _getshort(cp); 1998 cp += INT16SZ; /* len */ 1999 if (class != C_IN) { 2000 /* XXX - debug? syslog? */ 2001 cp += n; 2002 continue; /* XXX - had_error++ ? */ 2003 } 2004 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 2005 type == T_CNAME) { 2006 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 2007 if ((n < 0) || !(*name_ok)(tbuf)) { 2008 had_error++; 2009 continue; 2010 } 2011 cp += n; 2012 /* Get canonical name. */ 2013 n = strlen(tbuf) + 1; /* for the \0 */ 2014 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 2015 had_error++; 2016 continue; 2017 } 2018 strlcpy(bp, tbuf, ep - bp); 2019 canonname = bp; 2020 bp += n; 2021 continue; 2022 } 2023 if (qtype == T_ANY) { 2024 if (!(type == T_A || type == T_AAAA)) { 2025 cp += n; 2026 continue; 2027 } 2028 } else if (type != qtype) { 2029#ifdef DEBUG 2030 if (type != T_KEY && type != T_SIG && 2031 type != ns_t_dname) 2032 syslog(LOG_NOTICE|LOG_AUTH, 2033 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 2034 qname, p_class(C_IN), p_type(qtype), 2035 p_type(type)); 2036#endif 2037 cp += n; 2038 continue; /* XXX - had_error++ ? */ 2039 } 2040 switch (type) { 2041 case T_A: 2042 case T_AAAA: 2043 if (strcasecmp(canonname, bp) != 0) { 2044#ifdef DEBUG 2045 syslog(LOG_NOTICE|LOG_AUTH, 2046 AskedForGot, canonname, bp); 2047#endif 2048 cp += n; 2049 continue; /* XXX - had_error++ ? */ 2050 } 2051 if (type == T_A && n != INADDRSZ) { 2052 cp += n; 2053 continue; 2054 } 2055 if (type == T_AAAA && n != IN6ADDRSZ) { 2056 cp += n; 2057 continue; 2058 } 2059#ifdef FILTER_V4MAPPED 2060 if (type == T_AAAA) { 2061 struct in6_addr in6; 2062 memcpy(&in6, cp, sizeof(in6)); 2063 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 2064 cp += n; 2065 continue; 2066 } 2067 } 2068#endif 2069 if (!haveanswer) { 2070 int nn; 2071 2072 canonname = bp; 2073 nn = strlen(bp) + 1; /* for the \0 */ 2074 bp += nn; 2075 } 2076 2077 /* don't overwrite pai */ 2078 ai = *pai; 2079 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 2080 afd = find_afd(ai.ai_family); 2081 if (afd == NULL) { 2082 cp += n; 2083 continue; 2084 } 2085 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 2086 if (cur->ai_next == NULL) 2087 had_error++; 2088 while (cur && cur->ai_next) 2089 cur = cur->ai_next; 2090 cp += n; 2091 break; 2092 default: 2093 abort(); 2094 } 2095 if (!had_error) 2096 haveanswer++; 2097 } 2098 if (haveanswer) { 2099#if defined(RESOLVSORT) 2100 /* 2101 * We support only IPv4 address for backward 2102 * compatibility against gethostbyname(3). 2103 */ 2104 if (res->nsort && qtype == T_A) { 2105 if (addr4sort(&sentinel, res) < 0) { 2106 freeaddrinfo(sentinel.ai_next); 2107 RES_SET_H_ERRNO(res, NO_RECOVERY); 2108 return NULL; 2109 } 2110 } 2111#endif /*RESOLVSORT*/ 2112 if (!canonname) 2113 (void)get_canonname(pai, sentinel.ai_next, qname); 2114 else 2115 (void)get_canonname(pai, sentinel.ai_next, canonname); 2116 RES_SET_H_ERRNO(res, NETDB_SUCCESS); 2117 return sentinel.ai_next; 2118 } 2119 2120 RES_SET_H_ERRNO(res, NO_RECOVERY); 2121 return NULL; 2122} 2123 2124#ifdef RESOLVSORT 2125struct addr_ptr { 2126 struct addrinfo *ai; 2127 int aval; 2128}; 2129 2130static int 2131addr4sort(struct addrinfo *sentinel, res_state res) 2132{ 2133 struct addrinfo *ai; 2134 struct addr_ptr *addrs, addr; 2135 struct sockaddr_in *sin; 2136 int naddrs, i, j; 2137 int needsort = 0; 2138 2139 if (!sentinel) 2140 return -1; 2141 naddrs = 0; 2142 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 2143 naddrs++; 2144 if (naddrs < 2) 2145 return 0; /* We don't need sorting. */ 2146 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 2147 return -1; 2148 i = 0; 2149 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 2150 sin = (struct sockaddr_in *)ai->ai_addr; 2151 for (j = 0; (unsigned)j < res->nsort; j++) { 2152 if (res->sort_list[j].addr.s_addr == 2153 (sin->sin_addr.s_addr & res->sort_list[j].mask)) 2154 break; 2155 } 2156 addrs[i].ai = ai; 2157 addrs[i].aval = j; 2158 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 2159 needsort = i; 2160 i++; 2161 } 2162 if (!needsort) { 2163 free(addrs); 2164 return 0; 2165 } 2166 2167 while (needsort < naddrs) { 2168 for (j = needsort - 1; j >= 0; j--) { 2169 if (addrs[j].aval > addrs[j+1].aval) { 2170 addr = addrs[j]; 2171 addrs[j] = addrs[j + 1]; 2172 addrs[j + 1] = addr; 2173 } else 2174 break; 2175 } 2176 needsort++; 2177 } 2178 2179 ai = sentinel; 2180 for (i = 0; i < naddrs; ++i) { 2181 ai->ai_next = addrs[i].ai; 2182 ai = ai->ai_next; 2183 } 2184 ai->ai_next = NULL; 2185 free(addrs); 2186 return 0; 2187} 2188#endif /*RESOLVSORT*/ 2189 2190/*ARGSUSED*/ 2191static int 2192_dns_getaddrinfo(void *rv, void *cb_data, va_list ap) 2193{ 2194 struct addrinfo *ai; 2195 querybuf *buf, *buf2; 2196 const char *hostname; 2197 const struct addrinfo *pai; 2198 struct addrinfo sentinel, *cur; 2199 struct res_target q, q2; 2200 res_state res; 2201 2202 hostname = va_arg(ap, char *); 2203 pai = va_arg(ap, const struct addrinfo *); 2204 2205 memset(&q, 0, sizeof(q)); 2206 memset(&q2, 0, sizeof(q2)); 2207 memset(&sentinel, 0, sizeof(sentinel)); 2208 cur = &sentinel; 2209 2210 buf = malloc(sizeof(*buf)); 2211 if (!buf) { 2212 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2213 return NS_NOTFOUND; 2214 } 2215 buf2 = malloc(sizeof(*buf2)); 2216 if (!buf2) { 2217 free(buf); 2218 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2219 return NS_NOTFOUND; 2220 } 2221 2222 switch (pai->ai_family) { 2223 case AF_UNSPEC: 2224 q.name = hostname; 2225 q.qclass = C_IN; 2226 q.qtype = T_A; 2227 q.answer = buf->buf; 2228 q.anslen = sizeof(buf->buf); 2229 q.next = &q2; 2230 q2.name = hostname; 2231 q2.qclass = C_IN; 2232 q2.qtype = T_AAAA; 2233 q2.answer = buf2->buf; 2234 q2.anslen = sizeof(buf2->buf); 2235 break; 2236 case AF_INET: 2237 q.name = hostname; 2238 q.qclass = C_IN; 2239 q.qtype = T_A; 2240 q.answer = buf->buf; 2241 q.anslen = sizeof(buf->buf); 2242 break; 2243 case AF_INET6: 2244 q.name = hostname; 2245 q.qclass = C_IN; 2246 q.qtype = T_AAAA; 2247 q.answer = buf->buf; 2248 q.anslen = sizeof(buf->buf); 2249 break; 2250 default: 2251 free(buf); 2252 free(buf2); 2253 return NS_UNAVAIL; 2254 } 2255 2256 res = __res_state(); 2257 if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) { 2258 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2259 free(buf); 2260 free(buf2); 2261 return NS_NOTFOUND; 2262 } 2263 2264 if (res_searchN(hostname, &q, res) < 0) { 2265 free(buf); 2266 free(buf2); 2267 return NS_NOTFOUND; 2268 } 2269 /* prefer IPv6 */ 2270 if (q.next) { 2271 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res); 2272 if (ai) { 2273 cur->ai_next = ai; 2274 while (cur && cur->ai_next) 2275 cur = cur->ai_next; 2276 } 2277 } 2278 ai = getanswer(buf, q.n, q.name, q.qtype, pai, res); 2279 if (ai) 2280 cur->ai_next = ai; 2281 free(buf); 2282 free(buf2); 2283 if (sentinel.ai_next == NULL) 2284 switch (res->res_h_errno) { 2285 case HOST_NOT_FOUND: 2286 return NS_NOTFOUND; 2287 case TRY_AGAIN: 2288 return NS_TRYAGAIN; 2289 default: 2290 return NS_UNAVAIL; 2291 } 2292 *((struct addrinfo **)rv) = sentinel.ai_next; 2293 return NS_SUCCESS; 2294} 2295 2296static void 2297_sethtent(FILE **hostf) 2298{ 2299 if (!*hostf) 2300 *hostf = fopen(_PATH_HOSTS, "re"); 2301 else 2302 rewind(*hostf); 2303} 2304 2305static void 2306_endhtent(FILE **hostf) 2307{ 2308 if (*hostf) { 2309 (void) fclose(*hostf); 2310 *hostf = NULL; 2311 } 2312} 2313 2314static struct addrinfo * 2315_gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2316{ 2317 char *p; 2318 char *cp, *tname, *cname; 2319 struct addrinfo hints, *res0, *res; 2320 int error; 2321 const char *addr; 2322 char hostbuf[8*1024]; 2323 2324 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "re"))) 2325 return (NULL); 2326again: 2327 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 2328 return (NULL); 2329 if (*p == '#') 2330 goto again; 2331 cp = strpbrk(p, "#\n"); 2332 if (cp != NULL) 2333 *cp = '\0'; 2334 if (!(cp = strpbrk(p, " \t"))) 2335 goto again; 2336 *cp++ = '\0'; 2337 addr = p; 2338 cname = NULL; 2339 /* if this is not something we're looking for, skip it. */ 2340 while (cp && *cp) { 2341 if (*cp == ' ' || *cp == '\t') { 2342 cp++; 2343 continue; 2344 } 2345 tname = cp; 2346 if (cname == NULL) 2347 cname = cp; 2348 if ((cp = strpbrk(cp, " \t")) != NULL) 2349 *cp++ = '\0'; 2350 if (strcasecmp(name, tname) == 0) 2351 goto found; 2352 } 2353 goto again; 2354 2355found: 2356 /* we should not glob socktype/protocol here */ 2357 memset(&hints, 0, sizeof(hints)); 2358 hints.ai_family = pai->ai_family; 2359 hints.ai_socktype = SOCK_DGRAM; 2360 hints.ai_protocol = 0; 2361 hints.ai_flags = AI_NUMERICHOST; 2362 error = getaddrinfo(addr, "0", &hints, &res0); 2363 if (error) 2364 goto again; 2365#ifdef FILTER_V4MAPPED 2366 /* XXX should check all items in the chain */ 2367 if (res0->ai_family == AF_INET6 && 2368 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2369 freeaddrinfo(res0); 2370 goto again; 2371 } 2372#endif 2373 for (res = res0; res; res = res->ai_next) { 2374 /* cover it up */ 2375 res->ai_flags = pai->ai_flags; 2376 res->ai_socktype = pai->ai_socktype; 2377 res->ai_protocol = pai->ai_protocol; 2378 2379 if (pai->ai_flags & AI_CANONNAME) { 2380 if (get_canonname(pai, res, cname) != 0) { 2381 freeaddrinfo(res0); 2382 goto again; 2383 } 2384 } 2385 } 2386 return res0; 2387} 2388 2389/*ARGSUSED*/ 2390static int 2391_files_getaddrinfo(void *rv, void *cb_data, va_list ap) 2392{ 2393 const char *name; 2394 const struct addrinfo *pai; 2395 struct addrinfo sentinel, *cur; 2396 struct addrinfo *p; 2397 FILE *hostf = NULL; 2398 2399 name = va_arg(ap, char *); 2400 pai = va_arg(ap, struct addrinfo *); 2401 2402 memset(&sentinel, 0, sizeof(sentinel)); 2403 cur = &sentinel; 2404 2405 _sethtent(&hostf); 2406 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2407 cur->ai_next = p; 2408 while (cur && cur->ai_next) 2409 cur = cur->ai_next; 2410 } 2411 _endhtent(&hostf); 2412 2413 *((struct addrinfo **)rv) = sentinel.ai_next; 2414 if (sentinel.ai_next == NULL) 2415 return NS_NOTFOUND; 2416 return NS_SUCCESS; 2417} 2418 2419#ifdef YP 2420/*ARGSUSED*/ 2421static struct addrinfo * 2422_yphostent(char *line, const struct addrinfo *pai) 2423{ 2424 struct addrinfo sentinel, *cur; 2425 struct addrinfo hints, *res, *res0; 2426 int error; 2427 char *p = line; 2428 const char *addr, *canonname; 2429 char *nextline; 2430 char *cp; 2431 2432 addr = canonname = NULL; 2433 2434 memset(&sentinel, 0, sizeof(sentinel)); 2435 cur = &sentinel; 2436 2437nextline: 2438 /* terminate line */ 2439 cp = strchr(p, '\n'); 2440 if (cp) { 2441 *cp++ = '\0'; 2442 nextline = cp; 2443 } else 2444 nextline = NULL; 2445 2446 cp = strpbrk(p, " \t"); 2447 if (cp == NULL) { 2448 if (canonname == NULL) 2449 return (NULL); 2450 else 2451 goto done; 2452 } 2453 *cp++ = '\0'; 2454 2455 addr = p; 2456 2457 while (cp && *cp) { 2458 if (*cp == ' ' || *cp == '\t') { 2459 cp++; 2460 continue; 2461 } 2462 if (!canonname) 2463 canonname = cp; 2464 if ((cp = strpbrk(cp, " \t")) != NULL) 2465 *cp++ = '\0'; 2466 } 2467 2468 hints = *pai; 2469 hints.ai_flags = AI_NUMERICHOST; 2470 error = getaddrinfo(addr, NULL, &hints, &res0); 2471 if (error == 0) { 2472 for (res = res0; res; res = res->ai_next) { 2473 /* cover it up */ 2474 res->ai_flags = pai->ai_flags; 2475 2476 if (pai->ai_flags & AI_CANONNAME) 2477 (void)get_canonname(pai, res, canonname); 2478 } 2479 } else 2480 res0 = NULL; 2481 if (res0) { 2482 cur->ai_next = res0; 2483 while (cur && cur->ai_next) 2484 cur = cur->ai_next; 2485 } 2486 2487 if (nextline) { 2488 p = nextline; 2489 goto nextline; 2490 } 2491 2492done: 2493 return sentinel.ai_next; 2494} 2495 2496/*ARGSUSED*/ 2497static int 2498_yp_getaddrinfo(void *rv, void *cb_data, va_list ap) 2499{ 2500 struct addrinfo sentinel, *cur; 2501 struct addrinfo *ai = NULL; 2502 char *ypbuf; 2503 int ypbuflen, r; 2504 const char *name; 2505 const struct addrinfo *pai; 2506 char *ypdomain; 2507 2508 if (_yp_check(&ypdomain) == 0) 2509 return NS_UNAVAIL; 2510 2511 name = va_arg(ap, char *); 2512 pai = va_arg(ap, const struct addrinfo *); 2513 2514 memset(&sentinel, 0, sizeof(sentinel)); 2515 cur = &sentinel; 2516 2517 /* hosts.byname is only for IPv4 (Solaris8) */ 2518 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2519 r = yp_match(ypdomain, "hosts.byname", name, 2520 (int)strlen(name), &ypbuf, &ypbuflen); 2521 if (r == 0) { 2522 struct addrinfo ai4; 2523 2524 ai4 = *pai; 2525 ai4.ai_family = AF_INET; 2526 ai = _yphostent(ypbuf, &ai4); 2527 if (ai) { 2528 cur->ai_next = ai; 2529 while (cur && cur->ai_next) 2530 cur = cur->ai_next; 2531 } 2532 free(ypbuf); 2533 } 2534 } 2535 2536 /* ipnodes.byname can hold both IPv4/v6 */ 2537 r = yp_match(ypdomain, "ipnodes.byname", name, 2538 (int)strlen(name), &ypbuf, &ypbuflen); 2539 if (r == 0) { 2540 ai = _yphostent(ypbuf, pai); 2541 if (ai) 2542 cur->ai_next = ai; 2543 free(ypbuf); 2544 } 2545 2546 if (sentinel.ai_next == NULL) { 2547 RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND); 2548 return NS_NOTFOUND; 2549 } 2550 *((struct addrinfo **)rv) = sentinel.ai_next; 2551 return NS_SUCCESS; 2552} 2553#endif 2554 2555/* resolver logic */ 2556 2557/* 2558 * Formulate a normal query, send, and await answer. 2559 * Returned answer is placed in supplied buffer "answer". 2560 * Perform preliminary check of answer, returning success only 2561 * if no error is indicated and the answer count is nonzero. 2562 * Return the size of the response on success, -1 on error. 2563 * Error number is left in h_errno. 2564 * 2565 * Caller must parse answer and determine whether it answers the question. 2566 */ 2567static int 2568res_queryN(const char *name, struct res_target *target, res_state res) 2569{ 2570 u_char *buf; 2571 HEADER *hp; 2572 int n; 2573 u_int oflags; 2574 struct res_target *t; 2575 int rcode; 2576 int ancount; 2577 2578 rcode = NOERROR; 2579 ancount = 0; 2580 2581 buf = malloc(MAXPACKET); 2582 if (!buf) { 2583 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2584 return -1; 2585 } 2586 2587 for (t = target; t; t = t->next) { 2588 int class, type; 2589 u_char *answer; 2590 int anslen; 2591 2592 hp = (HEADER *)(void *)t->answer; 2593 2594 /* make it easier... */ 2595 class = t->qclass; 2596 type = t->qtype; 2597 answer = t->answer; 2598 anslen = t->anslen; 2599 2600 oflags = res->_flags; 2601 2602again: 2603 hp->rcode = NOERROR; /* default */ 2604 2605#ifdef DEBUG 2606 if (res->options & RES_DEBUG) 2607 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2608#endif 2609 2610 n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL, 2611 buf, MAXPACKET); 2612 if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 && 2613 (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U) 2614 n = res_nopt(res, n, buf, MAXPACKET, anslen); 2615 if (n <= 0) { 2616#ifdef DEBUG 2617 if (res->options & RES_DEBUG) 2618 printf(";; res_query: mkquery failed\n"); 2619#endif 2620 free(buf); 2621 RES_SET_H_ERRNO(res, NO_RECOVERY); 2622 return (n); 2623 } 2624 n = res_nsend(res, buf, n, answer, anslen); 2625 if (n < 0) { 2626 /* 2627 * if the query choked with EDNS0, retry 2628 * without EDNS0 2629 */ 2630 if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) 2631 != 0U && 2632 ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) { 2633 res->_flags |= RES_F_EDNS0ERR; 2634 if (res->options & RES_DEBUG) 2635 printf(";; res_nquery: retry without EDNS0\n"); 2636 goto again; 2637 } 2638 rcode = hp->rcode; /* record most recent error */ 2639#ifdef DEBUG 2640 if (res->options & RES_DEBUG) 2641 printf(";; res_query: send error\n"); 2642#endif 2643 continue; 2644 } 2645 2646 if (n > anslen) 2647 hp->rcode = FORMERR; /* XXX not very informative */ 2648 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2649 rcode = hp->rcode; /* record most recent error */ 2650#ifdef DEBUG 2651 if (res->options & RES_DEBUG) 2652 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2653 ntohs(hp->ancount)); 2654#endif 2655 continue; 2656 } 2657 2658 ancount += ntohs(hp->ancount); 2659 2660 t->n = n; 2661 } 2662 2663 free(buf); 2664 2665 if (ancount == 0) { 2666 switch (rcode) { 2667 case NXDOMAIN: 2668 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); 2669 break; 2670 case SERVFAIL: 2671 RES_SET_H_ERRNO(res, TRY_AGAIN); 2672 break; 2673 case NOERROR: 2674 RES_SET_H_ERRNO(res, NO_DATA); 2675 break; 2676 case FORMERR: 2677 case NOTIMP: 2678 case REFUSED: 2679 default: 2680 RES_SET_H_ERRNO(res, NO_RECOVERY); 2681 break; 2682 } 2683 return (-1); 2684 } 2685 return (ancount); 2686} 2687 2688/* 2689 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2690 * Return the size of the response on success, -1 on error. 2691 * If enabled, implement search rules until answer or unrecoverable failure 2692 * is detected. Error code, if any, is left in h_errno. 2693 */ 2694static int 2695res_searchN(const char *name, struct res_target *target, res_state res) 2696{ 2697 const char *cp, * const *domain; 2698 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2699 u_int dots; 2700 int trailing_dot, ret, saved_herrno; 2701 int got_nodata = 0, got_servfail = 0, root_on_list = 0; 2702 int tried_as_is = 0; 2703 int searched = 0; 2704 char abuf[MAXDNAME]; 2705 2706 errno = 0; 2707 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */ 2708 dots = 0; 2709 for (cp = name; *cp; cp++) 2710 dots += (*cp == '.'); 2711 trailing_dot = 0; 2712 if (cp > name && *--cp == '.') 2713 trailing_dot++; 2714 2715 /* 2716 * if there aren't any dots, it could be a user-level alias 2717 */ 2718 if (!dots && 2719 (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL) 2720 return (res_queryN(cp, target, res)); 2721 2722 /* 2723 * If there are enough dots in the name, let's just give it a 2724 * try 'as is'. The threshold can be set with the "ndots" option. 2725 * Also, query 'as is', if there is a trailing dot in the name. 2726 */ 2727 saved_herrno = -1; 2728 if (dots >= res->ndots || trailing_dot) { 2729 ret = res_querydomainN(name, NULL, target, res); 2730 if (ret > 0 || trailing_dot) 2731 return (ret); 2732 if (errno == ECONNREFUSED) { 2733 RES_SET_H_ERRNO(res, TRY_AGAIN); 2734 return (-1); 2735 } 2736 switch (res->res_h_errno) { 2737 case NO_DATA: 2738 case HOST_NOT_FOUND: 2739 break; 2740 case TRY_AGAIN: 2741 if (hp->rcode == SERVFAIL) 2742 break; 2743 /* FALLTHROUGH */ 2744 default: 2745 return (-1); 2746 } 2747 saved_herrno = res->res_h_errno; 2748 tried_as_is++; 2749 } 2750 2751 /* 2752 * We do at least one level of search if 2753 * - there is no dot and RES_DEFNAME is set, or 2754 * - there is at least one dot, there is no trailing dot, 2755 * and RES_DNSRCH is set. 2756 */ 2757 if ((!dots && (res->options & RES_DEFNAMES)) || 2758 (dots && !trailing_dot && (res->options & RES_DNSRCH))) { 2759 int done = 0; 2760 2761 for (domain = (const char * const *)res->dnsrch; 2762 *domain && !done; 2763 domain++) { 2764 searched = 1; 2765 2766 if (domain[0][0] == '\0' || 2767 (domain[0][0] == '.' && domain[0][1] == '\0')) 2768 root_on_list++; 2769 2770 if (root_on_list && tried_as_is) 2771 continue; 2772 2773 ret = res_querydomainN(name, *domain, target, res); 2774 if (ret > 0) 2775 return (ret); 2776 2777 /* 2778 * If no server present, give up. 2779 * If name isn't found in this domain, 2780 * keep trying higher domains in the search list 2781 * (if that's enabled). 2782 * On a NO_DATA error, keep trying, otherwise 2783 * a wildcard entry of another type could keep us 2784 * from finding this entry higher in the domain. 2785 * If we get some other error (negative answer or 2786 * server failure), then stop searching up, 2787 * but try the input name below in case it's 2788 * fully-qualified. 2789 */ 2790 if (errno == ECONNREFUSED) { 2791 RES_SET_H_ERRNO(res, TRY_AGAIN); 2792 return (-1); 2793 } 2794 2795 switch (res->res_h_errno) { 2796 case NO_DATA: 2797 got_nodata++; 2798 /* FALLTHROUGH */ 2799 case HOST_NOT_FOUND: 2800 /* keep trying */ 2801 break; 2802 case TRY_AGAIN: 2803 got_servfail++; 2804 if (hp->rcode == SERVFAIL) { 2805 /* try next search element, if any */ 2806 break; 2807 } 2808 /* FALLTHROUGH */ 2809 default: 2810 /* anything else implies that we're done */ 2811 done++; 2812 } 2813 /* 2814 * if we got here for some reason other than DNSRCH, 2815 * we only wanted one iteration of the loop, so stop. 2816 */ 2817 if (!(res->options & RES_DNSRCH)) 2818 done++; 2819 } 2820 } 2821 2822 switch (res->res_h_errno) { 2823 case NO_DATA: 2824 case HOST_NOT_FOUND: 2825 break; 2826 case TRY_AGAIN: 2827 if (hp->rcode == SERVFAIL) 2828 break; 2829 /* FALLTHROUGH */ 2830 default: 2831 goto giveup; 2832 } 2833 2834 /* 2835 * If the query has not already been tried as is then try it 2836 * unless RES_NOTLDQUERY is set and there were no dots. 2837 */ 2838 if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) && 2839 !(tried_as_is || root_on_list)) { 2840 ret = res_querydomainN(name, NULL, target, res); 2841 if (ret > 0) 2842 return (ret); 2843 } 2844 2845 /* 2846 * if we got here, we didn't satisfy the search. 2847 * if we did an initial full query, return that query's h_errno 2848 * (note that we wouldn't be here if that query had succeeded). 2849 * else if we ever got a nodata, send that back as the reason. 2850 * else send back meaningless h_errno, that being the one from 2851 * the last DNSRCH we did. 2852 */ 2853giveup: 2854 if (saved_herrno != -1) 2855 RES_SET_H_ERRNO(res, saved_herrno); 2856 else if (got_nodata) 2857 RES_SET_H_ERRNO(res, NO_DATA); 2858 else if (got_servfail) 2859 RES_SET_H_ERRNO(res, TRY_AGAIN); 2860 return (-1); 2861} 2862 2863/* 2864 * Perform a call on res_query on the concatenation of name and domain, 2865 * removing a trailing dot from name if domain is NULL. 2866 */ 2867static int 2868res_querydomainN(const char *name, const char *domain, 2869 struct res_target *target, res_state res) 2870{ 2871 char nbuf[MAXDNAME]; 2872 const char *longname = nbuf; 2873 size_t n, d; 2874 2875#ifdef DEBUG 2876 if (res->options & RES_DEBUG) 2877 printf(";; res_querydomain(%s, %s)\n", 2878 name, domain?domain:"<Nil>"); 2879#endif 2880 if (domain == NULL) { 2881 /* 2882 * Check for trailing '.'; 2883 * copy without '.' if present. 2884 */ 2885 n = strlen(name); 2886 if (n >= MAXDNAME) { 2887 RES_SET_H_ERRNO(res, NO_RECOVERY); 2888 return (-1); 2889 } 2890 if (n > 0 && name[--n] == '.') { 2891 strncpy(nbuf, name, n); 2892 nbuf[n] = '\0'; 2893 } else 2894 longname = name; 2895 } else { 2896 n = strlen(name); 2897 d = strlen(domain); 2898 if (n + d + 1 >= MAXDNAME) { 2899 RES_SET_H_ERRNO(res, NO_RECOVERY); 2900 return (-1); 2901 } 2902 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2903 } 2904 return (res_queryN(longname, target, res)); 2905} 2906