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: releng/10.3/lib/libc/net/getaddrinfo.c 292826 2015-12-28 03:37:13Z ume $"); 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 "netdb_private.h" 100#include "libc_private.h" 101#ifdef NS_CACHING 102#include "nscache.h" 103#endif 104 105#if defined(__KAME__) && defined(INET6) 106# define FAITH 107#endif 108 109#define ANY 0 110#define YES 1 111#define NO 0 112 113static const char in_addrany[] = { 0, 0, 0, 0 }; 114static const char in_loopback[] = { 127, 0, 0, 1 }; 115#ifdef INET6 116static const char in6_addrany[] = { 117 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 118}; 119static const char in6_loopback[] = { 120 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 121}; 122#endif 123 124struct policyqueue { 125 TAILQ_ENTRY(policyqueue) pc_entry; 126#ifdef INET6 127 struct in6_addrpolicy pc_policy; 128#endif 129}; 130TAILQ_HEAD(policyhead, policyqueue); 131 132static const struct afd { 133 int a_af; 134 int a_addrlen; 135 socklen_t a_socklen; 136 int a_off; 137 const char *a_addrany; 138 const char *a_loopback; 139 int a_scoped; 140} afdl [] = { 141#ifdef INET6 142#define N_INET6 0 143 {PF_INET6, sizeof(struct in6_addr), 144 sizeof(struct sockaddr_in6), 145 offsetof(struct sockaddr_in6, sin6_addr), 146 in6_addrany, in6_loopback, 1}, 147#define N_INET 1 148#else 149#define N_INET 0 150#endif 151 {PF_INET, sizeof(struct in_addr), 152 sizeof(struct sockaddr_in), 153 offsetof(struct sockaddr_in, sin_addr), 154 in_addrany, in_loopback, 0}, 155 {0, 0, 0, 0, NULL, NULL, 0}, 156}; 157 158struct explore { 159 int e_af; 160 int e_socktype; 161 int e_protocol; 162 int e_wild; 163#define WILD_AF(ex) ((ex)->e_wild & 0x01) 164#define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 165#define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 166}; 167 168static const struct explore explore[] = { 169#if 0 170 { PF_LOCAL, ANY, ANY, 0x01 }, 171#endif 172#ifdef INET6 173 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, 0x07 }, 174 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, 0x07 }, 175 { PF_INET6, SOCK_STREAM, IPPROTO_SCTP, 0x03 }, 176 { PF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 }, 177 { PF_INET6, SOCK_DGRAM, IPPROTO_UDPLITE, 0x03 }, 178 { PF_INET6, SOCK_RAW, ANY, 0x05 }, 179#endif 180 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, 0x07 }, 181 { PF_INET, SOCK_STREAM, IPPROTO_TCP, 0x07 }, 182 { PF_INET, SOCK_STREAM, IPPROTO_SCTP, 0x03 }, 183 { PF_INET, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 }, 184 { PF_INET, SOCK_DGRAM, IPPROTO_UDPLITE, 0x03 }, 185 { PF_INET, SOCK_RAW, ANY, 0x05 }, 186 { -1, 0, 0, 0 }, 187}; 188 189#ifdef INET6 190#define PTON_MAX 16 191#else 192#define PTON_MAX 4 193#endif 194 195#define AIO_SRCFLAG_DEPRECATED 0x1 196 197struct ai_order { 198 union { 199 struct sockaddr_storage aiou_ss; 200 struct sockaddr aiou_sa; 201 } aio_src_un; 202#define aio_srcsa aio_src_un.aiou_sa 203 u_int32_t aio_srcflag; 204 int aio_srcscope; 205 int aio_dstscope; 206 struct policyqueue *aio_srcpolicy; 207 struct policyqueue *aio_dstpolicy; 208 struct addrinfo *aio_ai; 209 int aio_matchlen; 210}; 211 212static const ns_src default_dns_files[] = { 213 { NSSRC_FILES, NS_SUCCESS }, 214 { NSSRC_DNS, NS_SUCCESS }, 215 { 0 } 216}; 217 218struct res_target { 219 struct res_target *next; 220 const char *name; /* domain name */ 221 int qclass, qtype; /* class and type of query */ 222 u_char *answer; /* buffer to put answer */ 223 int anslen; /* size of answer buffer */ 224 int n; /* result length */ 225}; 226 227#define MAXPACKET (64*1024) 228 229typedef union { 230 HEADER hdr; 231 u_char buf[MAXPACKET]; 232} querybuf; 233 234static int str2number(const char *, int *); 235static int explore_copy(const struct addrinfo *, const struct addrinfo *, 236 struct addrinfo **); 237static int explore_null(const struct addrinfo *, 238 const char *, struct addrinfo **); 239static int explore_numeric(const struct addrinfo *, const char *, 240 const char *, struct addrinfo **, const char *); 241static int explore_numeric_scope(const struct addrinfo *, const char *, 242 const char *, struct addrinfo **); 243static int get_canonname(const struct addrinfo *, 244 struct addrinfo *, const char *); 245static struct addrinfo *get_ai(const struct addrinfo *, 246 const struct afd *, const char *); 247static struct addrinfo *copy_ai(const struct addrinfo *); 248static int get_portmatch(const struct addrinfo *, const char *); 249static int get_port(struct addrinfo *, const char *, int); 250static const struct afd *find_afd(int); 251static int addrconfig(struct addrinfo *); 252#ifdef INET6 253static int is_ifdisabled(char *); 254#endif 255static void set_source(struct ai_order *, struct policyhead *); 256static int comp_dst(const void *, const void *); 257#ifdef INET6 258static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 259#endif 260static int gai_addr2scopetype(struct sockaddr *); 261 262static int explore_fqdn(const struct addrinfo *, const char *, 263 const char *, struct addrinfo **); 264 265static int reorder(struct addrinfo *); 266static int get_addrselectpolicy(struct policyhead *); 267static void free_addrselectpolicy(struct policyhead *); 268static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 269 struct policyhead *); 270static int matchlen(struct sockaddr *, struct sockaddr *); 271 272static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 273 const struct addrinfo *, res_state); 274#if defined(RESOLVSORT) 275static int addr4sort(struct addrinfo *, res_state); 276#endif 277static int _dns_getaddrinfo(void *, void *, va_list); 278static void _sethtent(FILE **); 279static void _endhtent(FILE **); 280static struct addrinfo *_gethtent(FILE **, const char *, 281 const struct addrinfo *); 282static int _files_getaddrinfo(void *, void *, va_list); 283#ifdef YP 284static struct addrinfo *_yphostent(char *, const struct addrinfo *); 285static int _yp_getaddrinfo(void *, void *, va_list); 286#endif 287#ifdef NS_CACHING 288static int addrinfo_id_func(char *, size_t *, va_list, void *); 289static int addrinfo_marshal_func(char *, size_t *, void *, va_list, void *); 290static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, void *); 291#endif 292 293static int res_queryN(const char *, struct res_target *, res_state); 294static int res_searchN(const char *, struct res_target *, res_state); 295static int res_querydomainN(const char *, const char *, 296 struct res_target *, res_state); 297 298/* XXX macros that make external reference is BAD. */ 299 300#define GET_AI(ai, afd, addr) \ 301do { \ 302 /* external reference: pai, error, and label free */ \ 303 (ai) = get_ai(pai, (afd), (addr)); \ 304 if ((ai) == NULL) { \ 305 error = EAI_MEMORY; \ 306 goto free; \ 307 } \ 308} while (/*CONSTCOND*/0) 309 310#define GET_PORT(ai, serv) \ 311do { \ 312 /* external reference: error and label free */ \ 313 error = get_port((ai), (serv), 0); \ 314 if (error != 0) \ 315 goto free; \ 316} while (/*CONSTCOND*/0) 317 318#define GET_CANONNAME(ai, str) \ 319do { \ 320 /* external reference: pai, error and label free */ \ 321 error = get_canonname(pai, (ai), (str)); \ 322 if (error != 0) \ 323 goto free; \ 324} while (/*CONSTCOND*/0) 325 326#define ERR(err) \ 327do { \ 328 /* external reference: error, and label bad */ \ 329 error = (err); \ 330 goto bad; \ 331 /*NOTREACHED*/ \ 332} while (/*CONSTCOND*/0) 333 334#define MATCH_FAMILY(x, y, w) \ 335 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 336#define MATCH(x, y, w) \ 337 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 338 339void 340freeaddrinfo(struct addrinfo *ai) 341{ 342 struct addrinfo *next; 343 344 do { 345 next = ai->ai_next; 346 if (ai->ai_canonname) 347 free(ai->ai_canonname); 348 /* no need to free(ai->ai_addr) */ 349 free(ai); 350 ai = next; 351 } while (ai); 352} 353 354static int 355str2number(const char *p, int *portp) 356{ 357 char *ep; 358 unsigned long v; 359 360 if (*p == '\0') 361 return -1; 362 ep = NULL; 363 errno = 0; 364 v = strtoul(p, &ep, 10); 365 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) { 366 *portp = v; 367 return 0; 368 } else 369 return -1; 370} 371 372int 373getaddrinfo(const char *hostname, const char *servname, 374 const struct addrinfo *hints, struct addrinfo **res) 375{ 376 struct addrinfo sentinel; 377 struct addrinfo *cur; 378 int error = 0; 379 struct addrinfo ai, ai0, *afai; 380 struct addrinfo *pai; 381 const struct afd *afd; 382 const struct explore *ex; 383 struct addrinfo *afailist[sizeof(afdl)/sizeof(afdl[0])]; 384 struct addrinfo *afai_unspec; 385 int found; 386 int numeric = 0; 387 388 /* ensure we return NULL on errors */ 389 *res = NULL; 390 391 memset(&ai, 0, sizeof(ai)); 392 393 memset(afailist, 0, sizeof(afailist)); 394 afai_unspec = NULL; 395 396 memset(&sentinel, 0, sizeof(sentinel)); 397 cur = &sentinel; 398 pai = &ai; 399 pai->ai_flags = 0; 400 pai->ai_family = PF_UNSPEC; 401 pai->ai_socktype = ANY; 402 pai->ai_protocol = ANY; 403 pai->ai_addrlen = 0; 404 pai->ai_canonname = NULL; 405 pai->ai_addr = NULL; 406 pai->ai_next = NULL; 407 408 if (hostname == NULL && servname == NULL) 409 return EAI_NONAME; 410 if (hints) { 411 /* error check for hints */ 412 if (hints->ai_addrlen || hints->ai_canonname || 413 hints->ai_addr || hints->ai_next) 414 ERR(EAI_BADHINTS); /* xxx */ 415 if (hints->ai_flags & ~AI_MASK) 416 ERR(EAI_BADFLAGS); 417 switch (hints->ai_family) { 418 case PF_UNSPEC: 419 case PF_INET: 420#ifdef INET6 421 case PF_INET6: 422#endif 423 break; 424 default: 425 ERR(EAI_FAMILY); 426 } 427 memcpy(pai, hints, sizeof(*pai)); 428 429 /* 430 * if both socktype/protocol are specified, check if they 431 * are meaningful combination. 432 */ 433 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 434 for (ex = explore; ex->e_af >= 0; ex++) { 435 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, 436 WILD_AF(ex))) 437 continue; 438 if (!MATCH(pai->ai_socktype, ex->e_socktype, 439 WILD_SOCKTYPE(ex))) 440 continue; 441 if (!MATCH(pai->ai_protocol, ex->e_protocol, 442 WILD_PROTOCOL(ex))) 443 continue; 444 445 /* matched */ 446 break; 447 } 448 449 if (ex->e_af < 0) 450 ERR(EAI_BADHINTS); 451 } 452 } 453 454 /* 455 * RFC 3493: AI_ALL and AI_V4MAPPED are effective only against 456 * AF_INET6 query. They need to be ignored if specified in other 457 * occassions. 458 */ 459 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 460 case AI_V4MAPPED: 461 case AI_ALL | AI_V4MAPPED: 462#ifdef INET6 463 if (pai->ai_family != AF_INET6) 464 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 465 break; 466#endif 467 case AI_ALL: 468 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 469 break; 470 } 471 472 /* 473 * check for special cases. (1) numeric servname is disallowed if 474 * socktype/protocol are left unspecified. (2) servname is disallowed 475 * for raw and other inet{,6} sockets. 476 */ 477 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 478#ifdef PF_INET6 479 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 480#endif 481 ) { 482 ai0 = *pai; /* backup *pai */ 483 484 if (pai->ai_family == PF_UNSPEC) { 485#ifdef PF_INET6 486 pai->ai_family = PF_INET6; 487#else 488 pai->ai_family = PF_INET; 489#endif 490 } 491 error = get_portmatch(pai, servname); 492 if (error) 493 goto bad; 494 495 *pai = ai0; 496 } 497 498 ai0 = *pai; 499 500 /* 501 * NULL hostname, or numeric hostname. 502 * If numeric representation of AF1 can be interpreted as FQDN 503 * representation of AF2, we need to think again about the code below. 504 */ 505 found = 0; 506 for (afd = afdl; afd->a_af; afd++) { 507 *pai = ai0; 508 509 if (!MATCH_FAMILY(pai->ai_family, afd->a_af, 1)) 510 continue; 511 512 if (pai->ai_family == PF_UNSPEC) 513 pai->ai_family = afd->a_af; 514 515 if (hostname == NULL) { 516 error = explore_null(pai, servname, 517 &afailist[afd - afdl]); 518 519 /* 520 * Errors from explore_null should be unexpected and 521 * be caught to avoid returning an incomplete result. 522 */ 523 if (error != 0) 524 goto bad; 525 } else { 526 error = explore_numeric_scope(pai, hostname, servname, 527 &afailist[afd - afdl]); 528 529 /* 530 * explore_numeric_scope returns an error for address 531 * families that do not match that of hostname. 532 * Thus we should not catch the error at this moment. 533 */ 534 } 535 536 if (!error && afailist[afd - afdl]) 537 found++; 538 } 539 if (found) { 540 numeric = 1; 541 goto globcopy; 542 } 543 544 if (hostname == NULL) 545 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 546 if (pai->ai_flags & AI_NUMERICHOST) 547 ERR(EAI_NONAME); 548 549 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 550 ERR(EAI_FAIL); 551 552 /* 553 * hostname as alphabetical name. 554 */ 555 *pai = ai0; 556 error = explore_fqdn(pai, hostname, servname, &afai_unspec); 557 558globcopy: 559 for (ex = explore; ex->e_af >= 0; ex++) { 560 *pai = ai0; 561 562 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 563 continue; 564 if (!MATCH(pai->ai_socktype, ex->e_socktype, 565 WILD_SOCKTYPE(ex))) 566 continue; 567 if (!MATCH(pai->ai_protocol, ex->e_protocol, 568 WILD_PROTOCOL(ex))) 569 continue; 570 571 if (pai->ai_family == PF_UNSPEC) 572 pai->ai_family = ex->e_af; 573 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 574 pai->ai_socktype = ex->e_socktype; 575 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 576 pai->ai_protocol = ex->e_protocol; 577 578 /* 579 * if the servname does not match socktype/protocol, ignore it. 580 */ 581 if (get_portmatch(pai, servname) != 0) 582 continue; 583 584 if (afai_unspec) 585 afai = afai_unspec; 586 else { 587 if ((afd = find_afd(pai->ai_family)) == NULL) 588 continue; 589 /* XXX assumes that afd points inside afdl[] */ 590 afai = afailist[afd - afdl]; 591 } 592 if (!afai) 593 continue; 594 595 error = explore_copy(pai, afai, &cur->ai_next); 596 if (error != 0) 597 goto bad; 598 599 while (cur && cur->ai_next) 600 cur = cur->ai_next; 601 } 602 603 /* 604 * ensure we return either: 605 * - error == 0, non-NULL *res 606 * - error != 0, NULL *res 607 */ 608 if (error == 0) { 609 if (sentinel.ai_next) { 610 /* 611 * If the returned entry is for an active connection, 612 * and the given name is not numeric, reorder the 613 * list, so that the application would try the list 614 * in the most efficient order. Since the head entry 615 * of the original list may contain ai_canonname and 616 * that entry may be moved elsewhere in the new list, 617 * we keep the pointer and will restore it in the new 618 * head entry. (Note that RFC3493 requires the head 619 * entry store it when requested by the caller). 620 */ 621 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 622 if (!numeric) { 623 char *canonname; 624 625 canonname = 626 sentinel.ai_next->ai_canonname; 627 sentinel.ai_next->ai_canonname = NULL; 628 (void)reorder(&sentinel); 629 if (sentinel.ai_next->ai_canonname == 630 NULL) { 631 sentinel.ai_next->ai_canonname 632 = canonname; 633 } else if (canonname != NULL) 634 free(canonname); 635 } 636 } 637 *res = sentinel.ai_next; 638 } else 639 error = EAI_FAIL; 640 } 641 642bad: 643 if (afai_unspec) 644 freeaddrinfo(afai_unspec); 645 for (afd = afdl; afd->a_af; afd++) { 646 if (afailist[afd - afdl]) 647 freeaddrinfo(afailist[afd - afdl]); 648 } 649 if (!*res) 650 if (sentinel.ai_next) 651 freeaddrinfo(sentinel.ai_next); 652 653 return (error); 654} 655 656static int 657reorder(struct addrinfo *sentinel) 658{ 659 struct addrinfo *ai, **aip; 660 struct ai_order *aio; 661 int i, n; 662 struct policyhead policyhead; 663 664 /* count the number of addrinfo elements for sorting. */ 665 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 666 ; 667 668 /* 669 * If the number is small enough, we can skip the reordering process. 670 */ 671 if (n <= 1) 672 return(n); 673 674 /* allocate a temporary array for sort and initialization of it. */ 675 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 676 return(n); /* give up reordering */ 677 memset(aio, 0, sizeof(*aio) * n); 678 679 /* retrieve address selection policy from the kernel */ 680 TAILQ_INIT(&policyhead); 681 if (!get_addrselectpolicy(&policyhead)) { 682 /* no policy is installed into kernel, we don't sort. */ 683 free(aio); 684 return (n); 685 } 686 687 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 688 aio[i].aio_ai = ai; 689 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 690 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 691 &policyhead); 692 set_source(&aio[i], &policyhead); 693 } 694 695 /* perform sorting. */ 696 qsort(aio, n, sizeof(*aio), comp_dst); 697 698 /* reorder the addrinfo chain. */ 699 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 700 *aip = aio[i].aio_ai; 701 aip = &aio[i].aio_ai->ai_next; 702 } 703 *aip = NULL; 704 705 /* cleanup and return */ 706 free(aio); 707 free_addrselectpolicy(&policyhead); 708 return(n); 709} 710 711static int 712get_addrselectpolicy(struct policyhead *head) 713{ 714#ifdef INET6 715 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 716 size_t l; 717 char *buf; 718 struct in6_addrpolicy *pol, *ep; 719 720 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 721 return (0); 722 if (l == 0) 723 return (0); 724 if ((buf = malloc(l)) == NULL) 725 return (0); 726 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 727 free(buf); 728 return (0); 729 } 730 731 ep = (struct in6_addrpolicy *)(buf + l); 732 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 733 struct policyqueue *new; 734 735 if ((new = malloc(sizeof(*new))) == NULL) { 736 free_addrselectpolicy(head); /* make the list empty */ 737 break; 738 } 739 new->pc_policy = *pol; 740 TAILQ_INSERT_TAIL(head, new, pc_entry); 741 } 742 743 free(buf); 744 return (1); 745#else 746 return (0); 747#endif 748} 749 750static void 751free_addrselectpolicy(struct policyhead *head) 752{ 753 struct policyqueue *ent, *nent; 754 755 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 756 nent = TAILQ_NEXT(ent, pc_entry); 757 TAILQ_REMOVE(head, ent, pc_entry); 758 free(ent); 759 } 760} 761 762static struct policyqueue * 763match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 764{ 765#ifdef INET6 766 struct policyqueue *ent, *bestent = NULL; 767 struct in6_addrpolicy *pol; 768 int matchlen, bestmatchlen = -1; 769 u_char *mp, *ep, *k, *p, m; 770 struct sockaddr_in6 key; 771 772 switch(addr->sa_family) { 773 case AF_INET6: 774 key = *(struct sockaddr_in6 *)addr; 775 break; 776 case AF_INET: 777 /* convert the address into IPv4-mapped IPv6 address. */ 778 memset(&key, 0, sizeof(key)); 779 key.sin6_family = AF_INET6; 780 key.sin6_len = sizeof(key); 781 _map_v4v6_address( 782 (char *)&((struct sockaddr_in *)addr)->sin_addr, 783 (char *)&key.sin6_addr); 784 break; 785 default: 786 return(NULL); 787 } 788 789 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 790 pol = &ent->pc_policy; 791 matchlen = 0; 792 793 mp = (u_char *)&pol->addrmask.sin6_addr; 794 ep = mp + 16; /* XXX: scope field? */ 795 k = (u_char *)&key.sin6_addr; 796 p = (u_char *)&pol->addr.sin6_addr; 797 for (; mp < ep && *mp; mp++, k++, p++) { 798 m = *mp; 799 if ((*k & m) != *p) 800 goto next; /* not match */ 801 if (m == 0xff) /* short cut for a typical case */ 802 matchlen += 8; 803 else { 804 while (m >= 0x80) { 805 matchlen++; 806 m <<= 1; 807 } 808 } 809 } 810 811 /* matched. check if this is better than the current best. */ 812 if (matchlen > bestmatchlen) { 813 bestent = ent; 814 bestmatchlen = matchlen; 815 } 816 817 next: 818 continue; 819 } 820 821 return(bestent); 822#else 823 return(NULL); 824#endif 825 826} 827 828static void 829set_source(struct ai_order *aio, struct policyhead *ph) 830{ 831 struct addrinfo ai = *aio->aio_ai; 832 struct sockaddr_storage ss; 833 socklen_t srclen; 834 int s; 835 836 /* set unspec ("no source is available"), just in case */ 837 aio->aio_srcsa.sa_family = AF_UNSPEC; 838 aio->aio_srcscope = -1; 839 840 switch(ai.ai_family) { 841 case AF_INET: 842#ifdef INET6 843 case AF_INET6: 844#endif 845 break; 846 default: /* ignore unsupported AFs explicitly */ 847 return; 848 } 849 850 /* XXX: make a dummy addrinfo to call connect() */ 851 ai.ai_socktype = SOCK_DGRAM; 852 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 853 ai.ai_next = NULL; 854 memset(&ss, 0, sizeof(ss)); 855 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 856 ai.ai_addr = (struct sockaddr *)&ss; 857 get_port(&ai, "1", 0); 858 859 /* open a socket to get the source address for the given dst */ 860 if ((s = _socket(ai.ai_family, ai.ai_socktype | SOCK_CLOEXEC, 861 ai.ai_protocol)) < 0) 862 return; /* give up */ 863#ifdef INET6 864 if (ai.ai_family == AF_INET6) { 865 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)ai.ai_addr; 866 int off = 0; 867 868 if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) 869 (void)_setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, 870 (char *)&off, sizeof(off)); 871 } 872#endif 873 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 874 goto cleanup; 875 srclen = ai.ai_addrlen; 876 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 877 aio->aio_srcsa.sa_family = AF_UNSPEC; 878 goto cleanup; 879 } 880 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 881 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 882 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 883#ifdef INET6 884 if (ai.ai_family == AF_INET6) { 885 struct in6_ifreq ifr6; 886 u_int32_t flags6; 887 888 memset(&ifr6, 0, sizeof(ifr6)); 889 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 890 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 891 flags6 = ifr6.ifr_ifru.ifru_flags6; 892 if ((flags6 & IN6_IFF_DEPRECATED)) 893 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 894 } 895 } 896#endif 897 898 cleanup: 899 _close(s); 900 return; 901} 902 903static int 904matchlen(struct sockaddr *src, struct sockaddr *dst) 905{ 906 int match = 0; 907 u_char *s, *d; 908 u_char *lim, r; 909 int addrlen; 910 911 switch (src->sa_family) { 912#ifdef INET6 913 case AF_INET6: 914 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 915 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 916 addrlen = sizeof(struct in6_addr); 917 lim = s + addrlen; 918 break; 919#endif 920 case AF_INET: 921 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; 922 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; 923 addrlen = sizeof(struct in_addr); 924 lim = s + addrlen; 925 break; 926 default: 927 return(0); 928 } 929 930 while (s < lim) 931 if ((r = (*d++ ^ *s++)) != 0) { 932 while (r < addrlen * 8) { 933 match++; 934 r <<= 1; 935 } 936 break; 937 } else 938 match += 8; 939 return(match); 940} 941 942static int 943comp_dst(const void *arg1, const void *arg2) 944{ 945 const struct ai_order *dst1 = arg1, *dst2 = arg2; 946 947 /* 948 * Rule 1: Avoid unusable destinations. 949 * XXX: we currently do not consider if an appropriate route exists. 950 */ 951 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 952 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 953 return(-1); 954 } 955 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 956 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 957 return(1); 958 } 959 960 /* Rule 2: Prefer matching scope. */ 961 if (dst1->aio_dstscope == dst1->aio_srcscope && 962 dst2->aio_dstscope != dst2->aio_srcscope) { 963 return(-1); 964 } 965 if (dst1->aio_dstscope != dst1->aio_srcscope && 966 dst2->aio_dstscope == dst2->aio_srcscope) { 967 return(1); 968 } 969 970 /* Rule 3: Avoid deprecated addresses. */ 971 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 972 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 973 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 974 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 975 return(-1); 976 } 977 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 978 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 979 return(1); 980 } 981 } 982 983 /* Rule 4: Prefer home addresses. */ 984 /* XXX: not implemented yet */ 985 986 /* Rule 5: Prefer matching label. */ 987#ifdef INET6 988 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 989 dst1->aio_srcpolicy->pc_policy.label == 990 dst1->aio_dstpolicy->pc_policy.label && 991 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 992 dst2->aio_srcpolicy->pc_policy.label != 993 dst2->aio_dstpolicy->pc_policy.label)) { 994 return(-1); 995 } 996 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 997 dst2->aio_srcpolicy->pc_policy.label == 998 dst2->aio_dstpolicy->pc_policy.label && 999 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 1000 dst1->aio_srcpolicy->pc_policy.label != 1001 dst1->aio_dstpolicy->pc_policy.label)) { 1002 return(1); 1003 } 1004#endif 1005 1006 /* Rule 6: Prefer higher precedence. */ 1007#ifdef INET6 1008 if (dst1->aio_dstpolicy && 1009 (dst2->aio_dstpolicy == NULL || 1010 dst1->aio_dstpolicy->pc_policy.preced > 1011 dst2->aio_dstpolicy->pc_policy.preced)) { 1012 return(-1); 1013 } 1014 if (dst2->aio_dstpolicy && 1015 (dst1->aio_dstpolicy == NULL || 1016 dst2->aio_dstpolicy->pc_policy.preced > 1017 dst1->aio_dstpolicy->pc_policy.preced)) { 1018 return(1); 1019 } 1020#endif 1021 1022 /* Rule 7: Prefer native transport. */ 1023 /* XXX: not implemented yet */ 1024 1025 /* Rule 8: Prefer smaller scope. */ 1026 if (dst1->aio_dstscope >= 0 && 1027 dst1->aio_dstscope < dst2->aio_dstscope) { 1028 return(-1); 1029 } 1030 if (dst2->aio_dstscope >= 0 && 1031 dst2->aio_dstscope < dst1->aio_dstscope) { 1032 return(1); 1033 } 1034 1035 /* 1036 * Rule 9: Use longest matching prefix. 1037 * We compare the match length in a same AF only. 1038 */ 1039 if (dst1->aio_ai->ai_addr->sa_family == 1040 dst2->aio_ai->ai_addr->sa_family && 1041 dst1->aio_ai->ai_addr->sa_family != AF_INET) { 1042 if (dst1->aio_matchlen > dst2->aio_matchlen) { 1043 return(-1); 1044 } 1045 if (dst1->aio_matchlen < dst2->aio_matchlen) { 1046 return(1); 1047 } 1048 } 1049 1050 /* Rule 10: Otherwise, leave the order unchanged. */ 1051 return(-1); 1052} 1053 1054/* 1055 * Copy from scope.c. 1056 * XXX: we should standardize the functions and link them as standard 1057 * library. 1058 */ 1059static int 1060gai_addr2scopetype(struct sockaddr *sa) 1061{ 1062#ifdef INET6 1063 struct sockaddr_in6 *sa6; 1064#endif 1065 struct sockaddr_in *sa4; 1066 1067 switch(sa->sa_family) { 1068#ifdef INET6 1069 case AF_INET6: 1070 sa6 = (struct sockaddr_in6 *)sa; 1071 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1072 /* just use the scope field of the multicast address */ 1073 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1074 } 1075 /* 1076 * Unicast addresses: map scope type to corresponding scope 1077 * value defined for multcast addresses. 1078 * XXX: hardcoded scope type values are bad... 1079 */ 1080 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1081 return(1); /* node local scope */ 1082 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1083 return(2); /* link-local scope */ 1084 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1085 return(5); /* site-local scope */ 1086 return(14); /* global scope */ 1087 break; 1088#endif 1089 case AF_INET: 1090 /* 1091 * IPv4 pseudo scoping according to RFC 3484. 1092 */ 1093 sa4 = (struct sockaddr_in *)sa; 1094 /* IPv4 autoconfiguration addresses have link-local scope. */ 1095 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1096 ((u_char *)&sa4->sin_addr)[1] == 254) 1097 return(2); 1098 /* Private addresses have site-local scope. */ 1099 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1100 (((u_char *)&sa4->sin_addr)[0] == 172 && 1101 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1102 (((u_char *)&sa4->sin_addr)[0] == 192 && 1103 ((u_char *)&sa4->sin_addr)[1] == 168)) 1104 return(14); /* XXX: It should be 5 unless NAT */ 1105 /* Loopback addresses have link-local scope. */ 1106 if (((u_char *)&sa4->sin_addr)[0] == 127) 1107 return(2); 1108 return(14); 1109 break; 1110 default: 1111 errno = EAFNOSUPPORT; /* is this a good error? */ 1112 return(-1); 1113 } 1114} 1115 1116static int 1117explore_copy(const struct addrinfo *pai, const struct addrinfo *src0, 1118 struct addrinfo **res) 1119{ 1120 int error; 1121 struct addrinfo sentinel, *cur; 1122 const struct addrinfo *src; 1123 1124 error = 0; 1125 sentinel.ai_next = NULL; 1126 cur = &sentinel; 1127 1128 for (src = src0; src != NULL; src = src->ai_next) { 1129 if (src->ai_family != pai->ai_family) 1130 continue; 1131 1132 cur->ai_next = copy_ai(src); 1133 if (!cur->ai_next) { 1134 error = EAI_MEMORY; 1135 goto fail; 1136 } 1137 1138 cur->ai_next->ai_socktype = pai->ai_socktype; 1139 cur->ai_next->ai_protocol = pai->ai_protocol; 1140 cur = cur->ai_next; 1141 } 1142 1143 *res = sentinel.ai_next; 1144 return 0; 1145 1146fail: 1147 freeaddrinfo(sentinel.ai_next); 1148 return error; 1149} 1150 1151/* 1152 * hostname == NULL. 1153 * passive socket -> anyaddr (0.0.0.0 or ::) 1154 * non-passive socket -> localhost (127.0.0.1 or ::1) 1155 */ 1156static int 1157explore_null(const struct addrinfo *pai, const char *servname, 1158 struct addrinfo **res) 1159{ 1160 int s; 1161 const struct afd *afd; 1162 struct addrinfo *ai; 1163 int error; 1164 1165 *res = NULL; 1166 ai = NULL; 1167 1168 /* 1169 * filter out AFs that are not supported by the kernel 1170 * XXX errno? 1171 */ 1172 s = _socket(pai->ai_family, SOCK_DGRAM | SOCK_CLOEXEC, 0); 1173 if (s < 0) { 1174 if (errno != EMFILE) 1175 return 0; 1176 } else 1177 _close(s); 1178 1179 afd = find_afd(pai->ai_family); 1180 if (afd == NULL) 1181 return 0; 1182 1183 if (pai->ai_flags & AI_PASSIVE) { 1184 GET_AI(ai, afd, afd->a_addrany); 1185 GET_PORT(ai, servname); 1186 } else { 1187 GET_AI(ai, afd, afd->a_loopback); 1188 GET_PORT(ai, servname); 1189 } 1190 1191 *res = ai; 1192 return 0; 1193 1194free: 1195 if (ai != NULL) 1196 freeaddrinfo(ai); 1197 return error; 1198} 1199 1200/* 1201 * numeric hostname 1202 */ 1203static int 1204explore_numeric(const struct addrinfo *pai, const char *hostname, 1205 const char *servname, struct addrinfo **res, const char *canonname) 1206{ 1207 const struct afd *afd; 1208 struct addrinfo *ai, ai0; 1209 int error; 1210 char pton[PTON_MAX]; 1211 1212 *res = NULL; 1213 ai = NULL; 1214 1215 afd = find_afd(pai->ai_family); 1216 if (afd == NULL) 1217 return 0; 1218 1219 switch (afd->a_af) { 1220 case AF_INET: 1221 /* 1222 * RFC3493 requires getaddrinfo() to accept AF_INET formats 1223 * that are accepted by inet_addr() and its family. The 1224 * accepted forms includes the "classful" one, which inet_pton 1225 * does not accept. So we need to separate the case for 1226 * AF_INET. 1227 */ 1228 if (inet_aton(hostname, (struct in_addr *)pton) != 1) 1229 return 0; 1230 break; 1231 default: 1232 if (inet_pton(afd->a_af, hostname, pton) != 1) { 1233 if (pai->ai_family != AF_INET6 || 1234 (pai->ai_flags & AI_V4MAPPED) != AI_V4MAPPED) 1235 return 0; 1236 if (inet_aton(hostname, (struct in_addr *)pton) != 1) 1237 return 0; 1238 afd = &afdl[N_INET]; 1239 ai0 = *pai; 1240 ai0.ai_family = AF_INET; 1241 pai = &ai0; 1242 } 1243 break; 1244 } 1245 1246 if (pai->ai_family == afd->a_af) { 1247 GET_AI(ai, afd, pton); 1248 GET_PORT(ai, servname); 1249 if ((pai->ai_flags & AI_CANONNAME)) { 1250 /* 1251 * Set the numeric address itself as the canonical 1252 * name, based on a clarification in RFC3493. 1253 */ 1254 GET_CANONNAME(ai, canonname); 1255 } 1256 } else { 1257 /* 1258 * XXX: This should not happen since we already matched the AF 1259 * by find_afd. 1260 */ 1261 ERR(EAI_FAMILY); 1262 } 1263 1264 *res = ai; 1265 return 0; 1266 1267free: 1268bad: 1269 if (ai != NULL) 1270 freeaddrinfo(ai); 1271 return error; 1272} 1273 1274/* 1275 * numeric hostname with scope 1276 */ 1277static int 1278explore_numeric_scope(const struct addrinfo *pai, const char *hostname, 1279 const char *servname, struct addrinfo **res) 1280{ 1281#if !defined(SCOPE_DELIMITER) || !defined(INET6) 1282 return explore_numeric(pai, hostname, servname, res, hostname); 1283#else 1284 const struct afd *afd; 1285 struct addrinfo *cur; 1286 int error; 1287 char *cp, *hostname2 = NULL, *scope, *addr; 1288 struct sockaddr_in6 *sin6; 1289 1290 afd = find_afd(pai->ai_family); 1291 if (afd == NULL) 1292 return 0; 1293 1294 if (!afd->a_scoped) 1295 return explore_numeric(pai, hostname, servname, res, hostname); 1296 1297 cp = strchr(hostname, SCOPE_DELIMITER); 1298 if (cp == NULL) 1299 return explore_numeric(pai, hostname, servname, res, hostname); 1300 1301 /* 1302 * Handle special case of <scoped_address><delimiter><scope id> 1303 */ 1304 hostname2 = strdup(hostname); 1305 if (hostname2 == NULL) 1306 return EAI_MEMORY; 1307 /* terminate at the delimiter */ 1308 hostname2[cp - hostname] = '\0'; 1309 addr = hostname2; 1310 scope = cp + 1; 1311 1312 error = explore_numeric(pai, addr, servname, res, hostname); 1313 if (error == 0) { 1314 u_int32_t scopeid; 1315 1316 for (cur = *res; cur; cur = cur->ai_next) { 1317 if (cur->ai_family != AF_INET6) 1318 continue; 1319 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1320 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1321 free(hostname2); 1322 freeaddrinfo(*res); 1323 *res = NULL; 1324 return(EAI_NONAME); /* XXX: is return OK? */ 1325 } 1326 sin6->sin6_scope_id = scopeid; 1327 } 1328 } 1329 1330 free(hostname2); 1331 1332 if (error && *res) { 1333 freeaddrinfo(*res); 1334 *res = NULL; 1335 } 1336 return error; 1337#endif 1338} 1339 1340static int 1341get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) 1342{ 1343 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1344 ai->ai_canonname = strdup(str); 1345 if (ai->ai_canonname == NULL) 1346 return EAI_MEMORY; 1347 } 1348 return 0; 1349} 1350 1351static struct addrinfo * 1352get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) 1353{ 1354 char *p; 1355 struct addrinfo *ai; 1356#ifdef FAITH 1357 struct in6_addr faith_prefix; 1358 char *fp_str; 1359 int translate = 0; 1360#endif 1361#ifdef INET6 1362 struct in6_addr mapaddr; 1363#endif 1364 1365#ifdef FAITH 1366 /* 1367 * Transfrom an IPv4 addr into a special IPv6 addr format for 1368 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1369 * 1370 * +-----------------------------------+------------+ 1371 * | faith prefix part (12 bytes) | embedded | 1372 * | | IPv4 addr part (4 bytes) 1373 * +-----------------------------------+------------+ 1374 * 1375 * faith prefix part is specified as ascii IPv6 addr format 1376 * in environmental variable GAI. 1377 * For FAITH to work correctly, routing to faith prefix must be 1378 * setup toward a machine where a FAITH daemon operates. 1379 * Also, the machine must enable some mechanizm 1380 * (e.g. faith interface hack) to divert those packet with 1381 * faith prefixed destination addr to user-land FAITH daemon. 1382 */ 1383 fp_str = getenv("GAI"); 1384 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1385 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1386 u_int32_t v4a; 1387 u_int8_t v4a_top; 1388 1389 memcpy(&v4a, addr, sizeof v4a); 1390 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1391 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1392 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1393 afd = &afdl[N_INET6]; 1394 memcpy(&faith_prefix.s6_addr[12], addr, 1395 sizeof(struct in_addr)); 1396 translate = 1; 1397 } 1398 } 1399#endif 1400 1401#ifdef INET6 1402 if (afd->a_af == AF_INET && (pai->ai_flags & AI_V4MAPPED) != 0) { 1403 afd = &afdl[N_INET6]; 1404 _map_v4v6_address(addr, (char *)&mapaddr); 1405 addr = (char *)&mapaddr; 1406 } 1407#endif 1408 1409 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1410 + (afd->a_socklen)); 1411 if (ai == NULL) 1412 return NULL; 1413 1414 memcpy(ai, pai, sizeof(struct addrinfo)); 1415 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1416 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1417 ai->ai_addr->sa_len = afd->a_socklen; 1418 ai->ai_addrlen = afd->a_socklen; 1419 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1420 p = (char *)(void *)(ai->ai_addr); 1421#ifdef FAITH 1422 if (translate == 1) 1423 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1424 else 1425#endif 1426 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1427 return ai; 1428} 1429 1430/* XXX need to malloc() the same way we do from other functions! */ 1431static struct addrinfo * 1432copy_ai(const struct addrinfo *pai) 1433{ 1434 struct addrinfo *ai; 1435 size_t l; 1436 1437 l = sizeof(*ai) + pai->ai_addrlen; 1438 if ((ai = (struct addrinfo *)malloc(l)) == NULL) 1439 return NULL; 1440 memset(ai, 0, l); 1441 memcpy(ai, pai, sizeof(*ai)); 1442 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1443 memcpy(ai->ai_addr, pai->ai_addr, pai->ai_addrlen); 1444 1445 if (pai->ai_canonname) { 1446 l = strlen(pai->ai_canonname) + 1; 1447 if ((ai->ai_canonname = malloc(l)) == NULL) { 1448 free(ai); 1449 return NULL; 1450 } 1451 strlcpy(ai->ai_canonname, pai->ai_canonname, l); 1452 } else { 1453 /* just to make sure */ 1454 ai->ai_canonname = NULL; 1455 } 1456 1457 ai->ai_next = NULL; 1458 1459 return ai; 1460} 1461 1462static int 1463get_portmatch(const struct addrinfo *ai, const char *servname) 1464{ 1465 1466 /* get_port does not touch first argument when matchonly == 1. */ 1467 /* LINTED const cast */ 1468 return get_port((struct addrinfo *)ai, servname, 1); 1469} 1470 1471static int 1472get_port(struct addrinfo *ai, const char *servname, int matchonly) 1473{ 1474 const char *proto; 1475 struct servent *sp; 1476 int port, error; 1477 int allownumeric; 1478 1479 if (servname == NULL) 1480 return 0; 1481 switch (ai->ai_family) { 1482 case AF_INET: 1483#ifdef AF_INET6 1484 case AF_INET6: 1485#endif 1486 break; 1487 default: 1488 return 0; 1489 } 1490 1491 switch (ai->ai_socktype) { 1492 case SOCK_RAW: 1493 return EAI_SERVICE; 1494 case SOCK_DGRAM: 1495 case SOCK_STREAM: 1496 case SOCK_SEQPACKET: 1497 allownumeric = 1; 1498 break; 1499 case ANY: 1500 switch (ai->ai_family) { 1501 case AF_INET: 1502#ifdef AF_INET6 1503 case AF_INET6: 1504#endif 1505 allownumeric = 1; 1506 break; 1507 default: 1508 allownumeric = 0; 1509 break; 1510 } 1511 break; 1512 default: 1513 return EAI_SOCKTYPE; 1514 } 1515 1516 error = str2number(servname, &port); 1517 if (error == 0) { 1518 if (!allownumeric) 1519 return EAI_SERVICE; 1520 if (port < 0 || port > 65535) 1521 return EAI_SERVICE; 1522 port = htons(port); 1523 } else { 1524 if (ai->ai_flags & AI_NUMERICSERV) 1525 return EAI_NONAME; 1526 1527 switch (ai->ai_protocol) { 1528 case IPPROTO_UDP: 1529 proto = "udp"; 1530 break; 1531 case IPPROTO_TCP: 1532 proto = "tcp"; 1533 break; 1534 case IPPROTO_SCTP: 1535 proto = "sctp"; 1536 break; 1537 case IPPROTO_UDPLITE: 1538 proto = "udplite"; 1539 break; 1540 default: 1541 proto = NULL; 1542 break; 1543 } 1544 1545 if ((sp = getservbyname(servname, proto)) == NULL) 1546 return EAI_SERVICE; 1547 port = sp->s_port; 1548 } 1549 1550 if (!matchonly) { 1551 switch (ai->ai_family) { 1552 case AF_INET: 1553 ((struct sockaddr_in *)(void *) 1554 ai->ai_addr)->sin_port = port; 1555 break; 1556#ifdef INET6 1557 case AF_INET6: 1558 ((struct sockaddr_in6 *)(void *) 1559 ai->ai_addr)->sin6_port = port; 1560 break; 1561#endif 1562 } 1563 } 1564 1565 return 0; 1566} 1567 1568static const struct afd * 1569find_afd(int af) 1570{ 1571 const struct afd *afd; 1572 1573 if (af == PF_UNSPEC) 1574 return NULL; 1575 for (afd = afdl; afd->a_af; afd++) { 1576 if (afd->a_af == af) 1577 return afd; 1578 } 1579 return NULL; 1580} 1581 1582/* 1583 * RFC 3493: AI_ADDRCONFIG check. Determines which address families are 1584 * configured on the local system and correlates with pai->ai_family value. 1585 * If an address family is not configured on the system, it will not be 1586 * queried for. For this purpose, loopback addresses are not considered 1587 * configured addresses. 1588 * 1589 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1590 * _dns_getaddrinfo. 1591 */ 1592static int 1593addrconfig(struct addrinfo *pai) 1594{ 1595 struct ifaddrs *ifaddrs, *ifa; 1596 struct sockaddr_in *sin; 1597#ifdef INET6 1598 struct sockaddr_in6 *sin6; 1599#endif 1600 int seen_inet = 0, seen_inet6 = 0; 1601 1602 if (getifaddrs(&ifaddrs) != 0) 1603 return (0); 1604 1605 for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) { 1606 if (ifa->ifa_addr == NULL || (ifa->ifa_flags & IFF_UP) == 0) 1607 continue; 1608 switch (ifa->ifa_addr->sa_family) { 1609 case AF_INET: 1610 if (seen_inet) 1611 continue; 1612 sin = (struct sockaddr_in *)(ifa->ifa_addr); 1613 if (htonl(sin->sin_addr.s_addr) == INADDR_LOOPBACK) 1614 continue; 1615 seen_inet = 1; 1616 break; 1617#ifdef INET6 1618 case AF_INET6: 1619 if (seen_inet6) 1620 continue; 1621 sin6 = (struct sockaddr_in6 *)(ifa->ifa_addr); 1622 if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr)) 1623 continue; 1624 if ((ifa->ifa_flags & IFT_LOOP) != 0 && 1625 IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) 1626 continue; 1627 if (is_ifdisabled(ifa->ifa_name)) 1628 continue; 1629 seen_inet6 = 1; 1630 break; 1631#endif 1632 } 1633 } 1634 freeifaddrs(ifaddrs); 1635 1636 switch(pai->ai_family) { 1637 case AF_INET6: 1638 return (seen_inet6); 1639 case AF_INET: 1640 return (seen_inet); 1641 case AF_UNSPEC: 1642 if (seen_inet == seen_inet6) 1643 return (seen_inet); 1644 pai->ai_family = seen_inet ? AF_INET : AF_INET6; 1645 return (1); 1646 } 1647 return (1); 1648} 1649 1650#ifdef INET6 1651static int 1652is_ifdisabled(char *name) 1653{ 1654 struct in6_ndireq nd; 1655 int fd; 1656 1657 if ((fd = _socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, 0)) < 0) 1658 return (-1); 1659 memset(&nd, 0, sizeof(nd)); 1660 strlcpy(nd.ifname, name, sizeof(nd.ifname)); 1661 if (_ioctl(fd, SIOCGIFINFO_IN6, &nd) < 0) { 1662 _close(fd); 1663 return (-1); 1664 } 1665 _close(fd); 1666 return ((nd.ndi.flags & ND6_IFF_IFDISABLED) != 0); 1667} 1668 1669/* convert a string to a scope identifier. XXX: IPv6 specific */ 1670static int 1671ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid) 1672{ 1673 u_long lscopeid; 1674 struct in6_addr *a6; 1675 char *ep; 1676 1677 a6 = &sin6->sin6_addr; 1678 1679 /* empty scopeid portion is invalid */ 1680 if (*scope == '\0') 1681 return -1; 1682 1683 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6) || 1684 IN6_IS_ADDR_MC_NODELOCAL(a6)) { 1685 /* 1686 * We currently assume a one-to-one mapping between links 1687 * and interfaces, so we simply use interface indices for 1688 * like-local scopes. 1689 */ 1690 *scopeid = if_nametoindex(scope); 1691 if (*scopeid == 0) 1692 goto trynumeric; 1693 return 0; 1694 } 1695 1696 /* still unclear about literal, allow numeric only - placeholder */ 1697 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1698 goto trynumeric; 1699 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1700 goto trynumeric; 1701 else 1702 goto trynumeric; /* global */ 1703 1704 /* try to convert to a numeric id as a last resort */ 1705 trynumeric: 1706 errno = 0; 1707 lscopeid = strtoul(scope, &ep, 10); 1708 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1709 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1710 return 0; 1711 else 1712 return -1; 1713} 1714#endif 1715 1716 1717#ifdef NS_CACHING 1718static int 1719addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap, 1720 void *cache_mdata) 1721{ 1722 res_state statp; 1723 u_long res_options; 1724 1725 const int op_id = 0; /* identifies the getaddrinfo for the cache */ 1726 char *hostname; 1727 struct addrinfo *hints; 1728 1729 char *p; 1730 int ai_flags, ai_family, ai_socktype, ai_protocol; 1731 size_t desired_size, size; 1732 1733 statp = __res_state(); 1734 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES | 1735 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6); 1736 1737 hostname = va_arg(ap, char *); 1738 hints = va_arg(ap, struct addrinfo *); 1739 1740 desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4; 1741 if (hostname != NULL) { 1742 size = strlen(hostname); 1743 desired_size += size + 1; 1744 } else 1745 size = 0; 1746 1747 if (desired_size > *buffer_size) { 1748 *buffer_size = desired_size; 1749 return (NS_RETURN); 1750 } 1751 1752 if (hints == NULL) 1753 ai_flags = ai_family = ai_socktype = ai_protocol = 0; 1754 else { 1755 ai_flags = hints->ai_flags; 1756 ai_family = hints->ai_family; 1757 ai_socktype = hints->ai_socktype; 1758 ai_protocol = hints->ai_protocol; 1759 } 1760 1761 p = buffer; 1762 memcpy(p, &res_options, sizeof(res_options)); 1763 p += sizeof(res_options); 1764 1765 memcpy(p, &op_id, sizeof(int)); 1766 p += sizeof(int); 1767 1768 memcpy(p, &ai_flags, sizeof(int)); 1769 p += sizeof(int); 1770 1771 memcpy(p, &ai_family, sizeof(int)); 1772 p += sizeof(int); 1773 1774 memcpy(p, &ai_socktype, sizeof(int)); 1775 p += sizeof(int); 1776 1777 memcpy(p, &ai_protocol, sizeof(int)); 1778 p += sizeof(int); 1779 1780 if (hostname != NULL) 1781 memcpy(p, hostname, size); 1782 1783 *buffer_size = desired_size; 1784 return (NS_SUCCESS); 1785} 1786 1787static int 1788addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval, 1789 va_list ap, void *cache_mdata) 1790{ 1791 struct addrinfo *ai, *cai; 1792 char *p; 1793 size_t desired_size, size, ai_size; 1794 1795 ai = *((struct addrinfo **)retval); 1796 1797 desired_size = sizeof(size_t); 1798 ai_size = 0; 1799 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1800 desired_size += sizeof(struct addrinfo) + cai->ai_addrlen; 1801 if (cai->ai_canonname != NULL) 1802 desired_size += sizeof(size_t) + 1803 strlen(cai->ai_canonname); 1804 ++ai_size; 1805 } 1806 1807 if (desired_size > *buffer_size) { 1808 /* this assignment is here for future use */ 1809 errno = ERANGE; 1810 *buffer_size = desired_size; 1811 return (NS_RETURN); 1812 } 1813 1814 memset(buffer, 0, desired_size); 1815 p = buffer; 1816 1817 memcpy(p, &ai_size, sizeof(size_t)); 1818 p += sizeof(size_t); 1819 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1820 memcpy(p, cai, sizeof(struct addrinfo)); 1821 p += sizeof(struct addrinfo); 1822 1823 memcpy(p, cai->ai_addr, cai->ai_addrlen); 1824 p += cai->ai_addrlen; 1825 1826 if (cai->ai_canonname != NULL) { 1827 size = strlen(cai->ai_canonname); 1828 memcpy(p, &size, sizeof(size_t)); 1829 p += sizeof(size_t); 1830 1831 memcpy(p, cai->ai_canonname, size); 1832 p += size; 1833 } 1834 } 1835 1836 return (NS_SUCCESS); 1837} 1838 1839static int 1840addrinfo_unmarshal_func(char *buffer, size_t buffer_size, void *retval, 1841 va_list ap, void *cache_mdata) 1842{ 1843 struct addrinfo new_ai, *result, *sentinel, *lasts; 1844 1845 char *p; 1846 size_t ai_size, ai_i, size; 1847 1848 p = buffer; 1849 memcpy(&ai_size, p, sizeof(size_t)); 1850 p += sizeof(size_t); 1851 1852 result = NULL; 1853 lasts = NULL; 1854 for (ai_i = 0; ai_i < ai_size; ++ai_i) { 1855 memcpy(&new_ai, p, sizeof(struct addrinfo)); 1856 p += sizeof(struct addrinfo); 1857 size = new_ai.ai_addrlen + sizeof(struct addrinfo) + 1858 _ALIGNBYTES; 1859 1860 sentinel = (struct addrinfo *)malloc(size); 1861 memset(sentinel, 0, size); 1862 1863 memcpy(sentinel, &new_ai, sizeof(struct addrinfo)); 1864 sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel + 1865 sizeof(struct addrinfo)); 1866 1867 memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen); 1868 p += new_ai.ai_addrlen; 1869 1870 if (new_ai.ai_canonname != NULL) { 1871 memcpy(&size, p, sizeof(size_t)); 1872 p += sizeof(size_t); 1873 1874 sentinel->ai_canonname = (char *)malloc(size + 1); 1875 memset(sentinel->ai_canonname, 0, size + 1); 1876 1877 memcpy(sentinel->ai_canonname, p, size); 1878 p += size; 1879 } 1880 1881 if (result == NULL) { 1882 result = sentinel; 1883 lasts = sentinel; 1884 } else { 1885 lasts->ai_next = sentinel; 1886 lasts = sentinel; 1887 } 1888 } 1889 1890 *((struct addrinfo **)retval) = result; 1891 return (NS_SUCCESS); 1892} 1893#endif /* NS_CACHING */ 1894 1895/* 1896 * FQDN hostname, DNS lookup 1897 */ 1898static int 1899explore_fqdn(const struct addrinfo *pai, const char *hostname, 1900 const char *servname, struct addrinfo **res) 1901{ 1902 struct addrinfo *result; 1903 struct addrinfo *cur; 1904 int error = 0; 1905 1906#ifdef NS_CACHING 1907 static const nss_cache_info cache_info = 1908 NS_COMMON_CACHE_INFO_INITIALIZER( 1909 hosts, NULL, addrinfo_id_func, addrinfo_marshal_func, 1910 addrinfo_unmarshal_func); 1911#endif 1912 static const ns_dtab dtab[] = { 1913 NS_FILES_CB(_files_getaddrinfo, NULL) 1914 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1915 NS_NIS_CB(_yp_getaddrinfo, NULL) 1916#ifdef NS_CACHING 1917 NS_CACHE_CB(&cache_info) 1918#endif 1919 { 0 } 1920 }; 1921 1922 result = NULL; 1923 1924 /* 1925 * if the servname does not match socktype/protocol, ignore it. 1926 */ 1927 if (get_portmatch(pai, servname) != 0) 1928 return 0; 1929 1930 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1931 default_dns_files, hostname, pai)) { 1932 case NS_TRYAGAIN: 1933 error = EAI_AGAIN; 1934 goto free; 1935 case NS_UNAVAIL: 1936 error = EAI_FAIL; 1937 goto free; 1938 case NS_NOTFOUND: 1939 error = EAI_NONAME; 1940 goto free; 1941 case NS_SUCCESS: 1942 error = 0; 1943 for (cur = result; cur; cur = cur->ai_next) { 1944 GET_PORT(cur, servname); 1945 /* canonname should be filled already */ 1946 } 1947 break; 1948 } 1949 1950 *res = result; 1951 1952 return 0; 1953 1954free: 1955 if (result) 1956 freeaddrinfo(result); 1957 return error; 1958} 1959 1960#ifdef DEBUG 1961static const char AskedForGot[] = 1962 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1963#endif 1964 1965static struct addrinfo * 1966getanswer(const querybuf *answer, int anslen, const char *qname, int qtype, 1967 const struct addrinfo *pai, res_state res) 1968{ 1969 struct addrinfo sentinel, *cur; 1970 struct addrinfo ai; 1971 const struct afd *afd; 1972 char *canonname; 1973 const HEADER *hp; 1974 const u_char *cp; 1975 int n; 1976 const u_char *eom; 1977 char *bp, *ep; 1978 int type, class, ancount, qdcount; 1979 int haveanswer, had_error; 1980 char tbuf[MAXDNAME]; 1981 int (*name_ok)(const char *); 1982 char hostbuf[8*1024]; 1983 1984 memset(&sentinel, 0, sizeof(sentinel)); 1985 cur = &sentinel; 1986 1987 canonname = NULL; 1988 eom = answer->buf + anslen; 1989 switch (qtype) { 1990 case T_A: 1991 case T_AAAA: 1992 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1993 name_ok = res_hnok; 1994 break; 1995 default: 1996 return (NULL); /* XXX should be abort(); */ 1997 } 1998 /* 1999 * find first satisfactory answer 2000 */ 2001 hp = &answer->hdr; 2002 ancount = ntohs(hp->ancount); 2003 qdcount = ntohs(hp->qdcount); 2004 bp = hostbuf; 2005 ep = hostbuf + sizeof hostbuf; 2006 cp = answer->buf + HFIXEDSZ; 2007 if (qdcount != 1) { 2008 RES_SET_H_ERRNO(res, NO_RECOVERY); 2009 return (NULL); 2010 } 2011 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 2012 if ((n < 0) || !(*name_ok)(bp)) { 2013 RES_SET_H_ERRNO(res, NO_RECOVERY); 2014 return (NULL); 2015 } 2016 cp += n + QFIXEDSZ; 2017 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 2018 /* res_send() has already verified that the query name is the 2019 * same as the one we sent; this just gets the expanded name 2020 * (i.e., with the succeeding search-domain tacked on). 2021 */ 2022 n = strlen(bp) + 1; /* for the \0 */ 2023 if (n >= MAXHOSTNAMELEN) { 2024 RES_SET_H_ERRNO(res, NO_RECOVERY); 2025 return (NULL); 2026 } 2027 canonname = bp; 2028 bp += n; 2029 /* The qname can be abbreviated, but h_name is now absolute. */ 2030 qname = canonname; 2031 } 2032 haveanswer = 0; 2033 had_error = 0; 2034 while (ancount-- > 0 && cp < eom && !had_error) { 2035 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 2036 if ((n < 0) || !(*name_ok)(bp)) { 2037 had_error++; 2038 continue; 2039 } 2040 cp += n; /* name */ 2041 type = _getshort(cp); 2042 cp += INT16SZ; /* type */ 2043 class = _getshort(cp); 2044 cp += INT16SZ + INT32SZ; /* class, TTL */ 2045 n = _getshort(cp); 2046 cp += INT16SZ; /* len */ 2047 if (class != C_IN) { 2048 /* XXX - debug? syslog? */ 2049 cp += n; 2050 continue; /* XXX - had_error++ ? */ 2051 } 2052 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 2053 type == T_CNAME) { 2054 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 2055 if ((n < 0) || !(*name_ok)(tbuf)) { 2056 had_error++; 2057 continue; 2058 } 2059 cp += n; 2060 /* Get canonical name. */ 2061 n = strlen(tbuf) + 1; /* for the \0 */ 2062 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 2063 had_error++; 2064 continue; 2065 } 2066 strlcpy(bp, tbuf, ep - bp); 2067 canonname = bp; 2068 bp += n; 2069 continue; 2070 } 2071 if (qtype == T_ANY) { 2072 if (!(type == T_A || type == T_AAAA)) { 2073 cp += n; 2074 continue; 2075 } 2076 } else if (type != qtype) { 2077#ifdef DEBUG 2078 if (type != T_KEY && type != T_SIG && 2079 type != ns_t_dname) 2080 syslog(LOG_NOTICE|LOG_AUTH, 2081 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 2082 qname, p_class(C_IN), p_type(qtype), 2083 p_type(type)); 2084#endif 2085 cp += n; 2086 continue; /* XXX - had_error++ ? */ 2087 } 2088 switch (type) { 2089 case T_A: 2090 case T_AAAA: 2091 if (strcasecmp(canonname, bp) != 0) { 2092#ifdef DEBUG 2093 syslog(LOG_NOTICE|LOG_AUTH, 2094 AskedForGot, canonname, bp); 2095#endif 2096 cp += n; 2097 continue; /* XXX - had_error++ ? */ 2098 } 2099 if (type == T_A && n != INADDRSZ) { 2100 cp += n; 2101 continue; 2102 } 2103 if (type == T_AAAA && n != IN6ADDRSZ) { 2104 cp += n; 2105 continue; 2106 } 2107#ifdef FILTER_V4MAPPED 2108 if (type == T_AAAA) { 2109 struct in6_addr in6; 2110 memcpy(&in6, cp, sizeof(in6)); 2111 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 2112 cp += n; 2113 continue; 2114 } 2115 } 2116#endif 2117 if (!haveanswer) { 2118 int nn; 2119 2120 canonname = bp; 2121 nn = strlen(bp) + 1; /* for the \0 */ 2122 bp += nn; 2123 } 2124 2125 /* don't overwrite pai */ 2126 ai = *pai; 2127 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 2128 afd = find_afd(ai.ai_family); 2129 if (afd == NULL) { 2130 cp += n; 2131 continue; 2132 } 2133 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 2134 if (cur->ai_next == NULL) 2135 had_error++; 2136 while (cur && cur->ai_next) 2137 cur = cur->ai_next; 2138 cp += n; 2139 break; 2140 default: 2141 abort(); 2142 } 2143 if (!had_error) 2144 haveanswer++; 2145 } 2146 if (haveanswer) { 2147#if defined(RESOLVSORT) 2148 /* 2149 * We support only IPv4 address for backward 2150 * compatibility against gethostbyname(3). 2151 */ 2152 if (res->nsort && qtype == T_A) { 2153 if (addr4sort(&sentinel, res) < 0) { 2154 freeaddrinfo(sentinel.ai_next); 2155 RES_SET_H_ERRNO(res, NO_RECOVERY); 2156 return NULL; 2157 } 2158 } 2159#endif /*RESOLVSORT*/ 2160 if (!canonname) 2161 (void)get_canonname(pai, sentinel.ai_next, qname); 2162 else 2163 (void)get_canonname(pai, sentinel.ai_next, canonname); 2164 RES_SET_H_ERRNO(res, NETDB_SUCCESS); 2165 return sentinel.ai_next; 2166 } 2167 2168 /* 2169 * We could have walked a CNAME chain, but the ultimate target 2170 * may not have what we looked for. 2171 */ 2172 RES_SET_H_ERRNO(res, ntohs(hp->ancount) > 0 ? NO_DATA : NO_RECOVERY); 2173 return NULL; 2174} 2175 2176#ifdef RESOLVSORT 2177struct addr_ptr { 2178 struct addrinfo *ai; 2179 int aval; 2180}; 2181 2182static int 2183addr4sort(struct addrinfo *sentinel, res_state res) 2184{ 2185 struct addrinfo *ai; 2186 struct addr_ptr *addrs, addr; 2187 struct sockaddr_in *sin; 2188 int naddrs, i, j; 2189 int needsort = 0; 2190 2191 if (!sentinel) 2192 return -1; 2193 naddrs = 0; 2194 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 2195 naddrs++; 2196 if (naddrs < 2) 2197 return 0; /* We don't need sorting. */ 2198 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 2199 return -1; 2200 i = 0; 2201 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 2202 sin = (struct sockaddr_in *)ai->ai_addr; 2203 for (j = 0; (unsigned)j < res->nsort; j++) { 2204 if (res->sort_list[j].addr.s_addr == 2205 (sin->sin_addr.s_addr & res->sort_list[j].mask)) 2206 break; 2207 } 2208 addrs[i].ai = ai; 2209 addrs[i].aval = j; 2210 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 2211 needsort = i; 2212 i++; 2213 } 2214 if (!needsort) { 2215 free(addrs); 2216 return 0; 2217 } 2218 2219 while (needsort < naddrs) { 2220 for (j = needsort - 1; j >= 0; j--) { 2221 if (addrs[j].aval > addrs[j+1].aval) { 2222 addr = addrs[j]; 2223 addrs[j] = addrs[j + 1]; 2224 addrs[j + 1] = addr; 2225 } else 2226 break; 2227 } 2228 needsort++; 2229 } 2230 2231 ai = sentinel; 2232 for (i = 0; i < naddrs; ++i) { 2233 ai->ai_next = addrs[i].ai; 2234 ai = ai->ai_next; 2235 } 2236 ai->ai_next = NULL; 2237 free(addrs); 2238 return 0; 2239} 2240#endif /*RESOLVSORT*/ 2241 2242/*ARGSUSED*/ 2243static int 2244_dns_getaddrinfo(void *rv, void *cb_data, va_list ap) 2245{ 2246 struct addrinfo *ai, ai0; 2247 querybuf *buf, *buf2; 2248 const char *hostname; 2249 const struct addrinfo *pai; 2250 struct addrinfo sentinel, *cur; 2251 struct res_target q, q2; 2252 res_state res; 2253 2254 hostname = va_arg(ap, char *); 2255 pai = va_arg(ap, const struct addrinfo *); 2256 2257 memset(&q, 0, sizeof(q)); 2258 memset(&q2, 0, sizeof(q2)); 2259 memset(&sentinel, 0, sizeof(sentinel)); 2260 cur = &sentinel; 2261 2262 res = __res_state(); 2263 2264 buf = malloc(sizeof(*buf)); 2265 if (!buf) { 2266 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2267 return NS_NOTFOUND; 2268 } 2269 buf2 = malloc(sizeof(*buf2)); 2270 if (!buf2) { 2271 free(buf); 2272 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2273 return NS_NOTFOUND; 2274 } 2275 2276 if (pai->ai_family == AF_INET6 && 2277 (pai->ai_flags & AI_V4MAPPED) == AI_V4MAPPED) { 2278 ai0 = *pai; 2279 ai0.ai_family = AF_UNSPEC; 2280 pai = &ai0; 2281 } 2282 2283 switch (pai->ai_family) { 2284 case AF_UNSPEC: 2285 q.name = hostname; 2286 q.qclass = C_IN; 2287 q.qtype = T_A; 2288 q.answer = buf->buf; 2289 q.anslen = sizeof(buf->buf); 2290 q.next = &q2; 2291 q2.name = hostname; 2292 q2.qclass = C_IN; 2293 q2.qtype = T_AAAA; 2294 q2.answer = buf2->buf; 2295 q2.anslen = sizeof(buf2->buf); 2296 break; 2297 case AF_INET: 2298 q.name = hostname; 2299 q.qclass = C_IN; 2300 q.qtype = T_A; 2301 q.answer = buf->buf; 2302 q.anslen = sizeof(buf->buf); 2303 break; 2304 case AF_INET6: 2305 q.name = hostname; 2306 q.qclass = C_IN; 2307 q.qtype = T_AAAA; 2308 q.answer = buf->buf; 2309 q.anslen = sizeof(buf->buf); 2310 break; 2311 default: 2312 free(buf); 2313 free(buf2); 2314 return NS_UNAVAIL; 2315 } 2316 2317 if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) { 2318 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2319 free(buf); 2320 free(buf2); 2321 return NS_NOTFOUND; 2322 } 2323 2324 if (res_searchN(hostname, &q, res) < 0) { 2325 free(buf); 2326 free(buf2); 2327 return NS_NOTFOUND; 2328 } 2329 /* prefer IPv6 */ 2330 if (q.next) { 2331 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res); 2332 if (ai) { 2333 cur->ai_next = ai; 2334 while (cur && cur->ai_next) 2335 cur = cur->ai_next; 2336 } 2337 } 2338 if (!ai || pai->ai_family != AF_UNSPEC || 2339 (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) != AI_V4MAPPED) { 2340 ai = getanswer(buf, q.n, q.name, q.qtype, pai, res); 2341 if (ai) 2342 cur->ai_next = ai; 2343 } 2344 free(buf); 2345 free(buf2); 2346 if (sentinel.ai_next == NULL) 2347 switch (res->res_h_errno) { 2348 case HOST_NOT_FOUND: 2349 case NO_DATA: 2350 return NS_NOTFOUND; 2351 case TRY_AGAIN: 2352 return NS_TRYAGAIN; 2353 default: 2354 return NS_UNAVAIL; 2355 } 2356 *((struct addrinfo **)rv) = sentinel.ai_next; 2357 return NS_SUCCESS; 2358} 2359 2360static void 2361_sethtent(FILE **hostf) 2362{ 2363 if (!*hostf) 2364 *hostf = fopen(_PATH_HOSTS, "re"); 2365 else 2366 rewind(*hostf); 2367} 2368 2369static void 2370_endhtent(FILE **hostf) 2371{ 2372 if (*hostf) { 2373 (void) fclose(*hostf); 2374 *hostf = NULL; 2375 } 2376} 2377 2378static struct addrinfo * 2379_gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2380{ 2381 char *p; 2382 char *cp, *tname, *cname; 2383 struct addrinfo hints, *res0, *res; 2384 int error; 2385 const char *addr; 2386 char hostbuf[8*1024]; 2387 2388 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "re"))) 2389 return (NULL); 2390again: 2391 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 2392 return (NULL); 2393 if (*p == '#') 2394 goto again; 2395 cp = strpbrk(p, "#\n"); 2396 if (cp != NULL) 2397 *cp = '\0'; 2398 if (!(cp = strpbrk(p, " \t"))) 2399 goto again; 2400 *cp++ = '\0'; 2401 addr = p; 2402 cname = NULL; 2403 /* if this is not something we're looking for, skip it. */ 2404 while (cp && *cp) { 2405 if (*cp == ' ' || *cp == '\t') { 2406 cp++; 2407 continue; 2408 } 2409 tname = cp; 2410 if (cname == NULL) 2411 cname = cp; 2412 if ((cp = strpbrk(cp, " \t")) != NULL) 2413 *cp++ = '\0'; 2414 if (strcasecmp(name, tname) == 0) 2415 goto found; 2416 } 2417 goto again; 2418 2419found: 2420 /* we should not glob socktype/protocol here */ 2421 memset(&hints, 0, sizeof(hints)); 2422 hints.ai_family = pai->ai_family; 2423 hints.ai_socktype = SOCK_DGRAM; 2424 hints.ai_protocol = 0; 2425 hints.ai_flags = AI_NUMERICHOST; 2426 if (pai->ai_family == AF_INET6 && 2427 (pai->ai_flags & AI_V4MAPPED) == AI_V4MAPPED) 2428 hints.ai_flags |= AI_V4MAPPED; 2429 error = getaddrinfo(addr, "0", &hints, &res0); 2430 if (error) 2431 goto again; 2432#ifdef FILTER_V4MAPPED 2433 /* XXX should check all items in the chain */ 2434 if (res0->ai_family == AF_INET6 && 2435 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2436 freeaddrinfo(res0); 2437 goto again; 2438 } 2439#endif 2440 for (res = res0; res; res = res->ai_next) { 2441 /* cover it up */ 2442 res->ai_flags = pai->ai_flags; 2443 res->ai_socktype = pai->ai_socktype; 2444 res->ai_protocol = pai->ai_protocol; 2445 2446 if (pai->ai_flags & AI_CANONNAME) { 2447 if (get_canonname(pai, res, cname) != 0) { 2448 freeaddrinfo(res0); 2449 goto again; 2450 } 2451 } 2452 } 2453 return res0; 2454} 2455 2456static struct addrinfo * 2457_getht(FILE **hostf, const char *name, const struct addrinfo *pai, 2458 struct addrinfo *cur) 2459{ 2460 struct addrinfo *p; 2461 2462 while ((p = _gethtent(hostf, name, pai)) != NULL) { 2463 cur->ai_next = p; 2464 while (cur && cur->ai_next) 2465 cur = cur->ai_next; 2466 } 2467 return (cur); 2468} 2469 2470/*ARGSUSED*/ 2471static int 2472_files_getaddrinfo(void *rv, void *cb_data, va_list ap) 2473{ 2474 const char *name; 2475 const struct addrinfo *pai; 2476 struct addrinfo sentinel, *cur; 2477 FILE *hostf = NULL; 2478 2479 name = va_arg(ap, char *); 2480 pai = va_arg(ap, struct addrinfo *); 2481 2482 memset(&sentinel, 0, sizeof(sentinel)); 2483 cur = &sentinel; 2484 2485 _sethtent(&hostf); 2486 if (pai->ai_family == AF_INET6 && 2487 (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) == AI_V4MAPPED) { 2488 struct addrinfo ai0 = *pai; 2489 2490 ai0.ai_flags &= ~AI_V4MAPPED; 2491 cur = _getht(&hostf, name, &ai0, cur); 2492 if (sentinel.ai_next == NULL) { 2493 _sethtent(&hostf); 2494 ai0.ai_flags |= AI_V4MAPPED; 2495 cur = _getht(&hostf, name, &ai0, cur); 2496 } 2497 } else 2498 cur = _getht(&hostf, name, pai, cur); 2499 _endhtent(&hostf); 2500 2501 *((struct addrinfo **)rv) = sentinel.ai_next; 2502 if (sentinel.ai_next == NULL) 2503 return NS_NOTFOUND; 2504 return NS_SUCCESS; 2505} 2506 2507#ifdef YP 2508/*ARGSUSED*/ 2509static struct addrinfo * 2510_yphostent(char *line, const struct addrinfo *pai) 2511{ 2512 struct addrinfo sentinel, *cur; 2513 struct addrinfo hints, *res, *res0; 2514 int error; 2515 char *p = line; 2516 const char *addr, *canonname; 2517 char *nextline; 2518 char *cp; 2519 2520 addr = canonname = NULL; 2521 2522 memset(&sentinel, 0, sizeof(sentinel)); 2523 cur = &sentinel; 2524 2525nextline: 2526 /* terminate line */ 2527 cp = strchr(p, '\n'); 2528 if (cp) { 2529 *cp++ = '\0'; 2530 nextline = cp; 2531 } else 2532 nextline = NULL; 2533 2534 cp = strpbrk(p, " \t"); 2535 if (cp == NULL) { 2536 if (canonname == NULL) 2537 return (NULL); 2538 else 2539 goto done; 2540 } 2541 *cp++ = '\0'; 2542 2543 addr = p; 2544 2545 while (cp && *cp) { 2546 if (*cp == ' ' || *cp == '\t') { 2547 cp++; 2548 continue; 2549 } 2550 if (!canonname) 2551 canonname = cp; 2552 if ((cp = strpbrk(cp, " \t")) != NULL) 2553 *cp++ = '\0'; 2554 } 2555 2556 hints = *pai; 2557 hints.ai_flags = AI_NUMERICHOST; 2558 if (pai->ai_family == AF_INET6 && 2559 (pai->ai_flags & AI_V4MAPPED) == AI_V4MAPPED) 2560 hints.ai_flags |= AI_V4MAPPED; 2561 error = getaddrinfo(addr, NULL, &hints, &res0); 2562 if (error == 0) { 2563 for (res = res0; res; res = res->ai_next) { 2564 /* cover it up */ 2565 res->ai_flags = pai->ai_flags; 2566 2567 if (pai->ai_flags & AI_CANONNAME) 2568 (void)get_canonname(pai, res, canonname); 2569 } 2570 } else 2571 res0 = NULL; 2572 if (res0) { 2573 cur->ai_next = res0; 2574 while (cur && cur->ai_next) 2575 cur = cur->ai_next; 2576 } 2577 2578 if (nextline) { 2579 p = nextline; 2580 goto nextline; 2581 } 2582 2583done: 2584 return sentinel.ai_next; 2585} 2586 2587/*ARGSUSED*/ 2588static int 2589_yp_getaddrinfo(void *rv, void *cb_data, va_list ap) 2590{ 2591 struct addrinfo sentinel, *cur; 2592 struct addrinfo *ai = NULL; 2593 char *ypbuf; 2594 int ypbuflen, r; 2595 const char *name; 2596 const struct addrinfo *pai; 2597 char *ypdomain; 2598 2599 if (_yp_check(&ypdomain) == 0) 2600 return NS_UNAVAIL; 2601 2602 name = va_arg(ap, char *); 2603 pai = va_arg(ap, const struct addrinfo *); 2604 2605 memset(&sentinel, 0, sizeof(sentinel)); 2606 cur = &sentinel; 2607 2608 /* ipnodes.byname can hold both IPv4/v6 */ 2609 r = yp_match(ypdomain, "ipnodes.byname", name, 2610 (int)strlen(name), &ypbuf, &ypbuflen); 2611 if (r == 0) { 2612 ai = _yphostent(ypbuf, pai); 2613 if (ai) { 2614 cur->ai_next = ai; 2615 while (cur && cur->ai_next) 2616 cur = cur->ai_next; 2617 } 2618 free(ypbuf); 2619 } 2620 2621 if (ai != NULL) { 2622 struct sockaddr_in6 *sin6; 2623 2624 switch (ai->ai_family) { 2625 case AF_INET: 2626 goto done; 2627 case AF_INET6: 2628 sin6 = (struct sockaddr_in6 *)ai->ai_addr; 2629 if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) 2630 goto done; 2631 break; 2632 } 2633 } 2634 2635 /* hosts.byname is only for IPv4 (Solaris8) */ 2636 if (pai->ai_family == AF_UNSPEC || pai->ai_family == AF_INET || 2637 ((pai->ai_family == AF_INET6 && 2638 (pai->ai_flags & AI_V4MAPPED) == AI_V4MAPPED) && 2639 (ai == NULL || (pai->ai_flags & AI_ALL) == AI_ALL))) { 2640 r = yp_match(ypdomain, "hosts.byname", name, 2641 (int)strlen(name), &ypbuf, &ypbuflen); 2642 if (r == 0) { 2643 struct addrinfo ai4; 2644 2645 ai4 = *pai; 2646 if (pai->ai_family == AF_UNSPEC) 2647 ai4.ai_family = AF_INET; 2648 ai = _yphostent(ypbuf, &ai4); 2649 if (ai) { 2650 cur->ai_next = ai; 2651 while (cur && cur->ai_next) 2652 cur = cur->ai_next; 2653 } 2654 free(ypbuf); 2655 } 2656 } 2657 2658done: 2659 if (sentinel.ai_next == NULL) { 2660 RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND); 2661 return NS_NOTFOUND; 2662 } 2663 *((struct addrinfo **)rv) = sentinel.ai_next; 2664 return NS_SUCCESS; 2665} 2666#endif 2667 2668/* resolver logic */ 2669 2670/* 2671 * Formulate a normal query, send, and await answer. 2672 * Returned answer is placed in supplied buffer "answer". 2673 * Perform preliminary check of answer, returning success only 2674 * if no error is indicated and the answer count is nonzero. 2675 * Return the size of the response on success, -1 on error. 2676 * Error number is left in h_errno. 2677 * 2678 * Caller must parse answer and determine whether it answers the question. 2679 */ 2680static int 2681res_queryN(const char *name, struct res_target *target, res_state res) 2682{ 2683 u_char *buf; 2684 HEADER *hp; 2685 int n; 2686 u_int oflags; 2687 struct res_target *t; 2688 int rcode; 2689 int ancount; 2690 2691 rcode = NOERROR; 2692 ancount = 0; 2693 2694 buf = malloc(MAXPACKET); 2695 if (!buf) { 2696 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2697 return -1; 2698 } 2699 2700 for (t = target; t; t = t->next) { 2701 int class, type; 2702 u_char *answer; 2703 int anslen; 2704 2705 hp = (HEADER *)(void *)t->answer; 2706 2707 /* make it easier... */ 2708 class = t->qclass; 2709 type = t->qtype; 2710 answer = t->answer; 2711 anslen = t->anslen; 2712 2713 oflags = res->_flags; 2714 2715again: 2716 hp->rcode = NOERROR; /* default */ 2717 2718#ifdef DEBUG 2719 if (res->options & RES_DEBUG) 2720 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2721#endif 2722 2723 n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL, 2724 buf, MAXPACKET); 2725 if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 && 2726 (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U) 2727 n = res_nopt(res, n, buf, MAXPACKET, anslen); 2728 if (n <= 0) { 2729#ifdef DEBUG 2730 if (res->options & RES_DEBUG) 2731 printf(";; res_query: mkquery failed\n"); 2732#endif 2733 free(buf); 2734 RES_SET_H_ERRNO(res, NO_RECOVERY); 2735 return (n); 2736 } 2737 n = res_nsend(res, buf, n, answer, anslen); 2738 if (n < 0) { 2739 /* 2740 * if the query choked with EDNS0, retry 2741 * without EDNS0 2742 */ 2743 if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) 2744 != 0U && 2745 ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) { 2746 res->_flags |= RES_F_EDNS0ERR; 2747 if (res->options & RES_DEBUG) 2748 printf(";; res_nquery: retry without EDNS0\n"); 2749 goto again; 2750 } 2751 rcode = hp->rcode; /* record most recent error */ 2752#ifdef DEBUG 2753 if (res->options & RES_DEBUG) 2754 printf(";; res_query: send error\n"); 2755#endif 2756 continue; 2757 } 2758 2759 if (n > anslen) 2760 hp->rcode = FORMERR; /* XXX not very informative */ 2761 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2762 rcode = hp->rcode; /* record most recent error */ 2763#ifdef DEBUG 2764 if (res->options & RES_DEBUG) 2765 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2766 ntohs(hp->ancount)); 2767#endif 2768 continue; 2769 } 2770 2771 ancount += ntohs(hp->ancount); 2772 2773 t->n = n; 2774 } 2775 2776 free(buf); 2777 2778 if (ancount == 0) { 2779 switch (rcode) { 2780 case NXDOMAIN: 2781 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); 2782 break; 2783 case SERVFAIL: 2784 RES_SET_H_ERRNO(res, TRY_AGAIN); 2785 break; 2786 case NOERROR: 2787 RES_SET_H_ERRNO(res, NO_DATA); 2788 break; 2789 case FORMERR: 2790 case NOTIMP: 2791 case REFUSED: 2792 default: 2793 RES_SET_H_ERRNO(res, NO_RECOVERY); 2794 break; 2795 } 2796 return (-1); 2797 } 2798 return (ancount); 2799} 2800 2801/* 2802 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2803 * Return the size of the response on success, -1 on error. 2804 * If enabled, implement search rules until answer or unrecoverable failure 2805 * is detected. Error code, if any, is left in h_errno. 2806 */ 2807static int 2808res_searchN(const char *name, struct res_target *target, res_state res) 2809{ 2810 const char *cp, * const *domain; 2811 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2812 u_int dots; 2813 int trailing_dot, ret, saved_herrno; 2814 int got_nodata = 0, got_servfail = 0, root_on_list = 0; 2815 int tried_as_is = 0; 2816 int searched = 0; 2817 char abuf[MAXDNAME]; 2818 2819 errno = 0; 2820 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */ 2821 dots = 0; 2822 for (cp = name; *cp; cp++) 2823 dots += (*cp == '.'); 2824 trailing_dot = 0; 2825 if (cp > name && *--cp == '.') 2826 trailing_dot++; 2827 2828 /* 2829 * if there aren't any dots, it could be a user-level alias 2830 */ 2831 if (!dots && 2832 (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL) 2833 return (res_queryN(cp, target, res)); 2834 2835 /* 2836 * If there are enough dots in the name, let's just give it a 2837 * try 'as is'. The threshold can be set with the "ndots" option. 2838 * Also, query 'as is', if there is a trailing dot in the name. 2839 */ 2840 saved_herrno = -1; 2841 if (dots >= res->ndots || trailing_dot) { 2842 ret = res_querydomainN(name, NULL, target, res); 2843 if (ret > 0 || trailing_dot) 2844 return (ret); 2845 if (errno == ECONNREFUSED) { 2846 RES_SET_H_ERRNO(res, TRY_AGAIN); 2847 return (-1); 2848 } 2849 switch (res->res_h_errno) { 2850 case NO_DATA: 2851 case HOST_NOT_FOUND: 2852 break; 2853 case TRY_AGAIN: 2854 if (hp->rcode == SERVFAIL) 2855 break; 2856 /* FALLTHROUGH */ 2857 default: 2858 return (-1); 2859 } 2860 saved_herrno = res->res_h_errno; 2861 tried_as_is++; 2862 } 2863 2864 /* 2865 * We do at least one level of search if 2866 * - there is no dot and RES_DEFNAME is set, or 2867 * - there is at least one dot, there is no trailing dot, 2868 * and RES_DNSRCH is set. 2869 */ 2870 if ((!dots && (res->options & RES_DEFNAMES)) || 2871 (dots && !trailing_dot && (res->options & RES_DNSRCH))) { 2872 int done = 0; 2873 2874 for (domain = (const char * const *)res->dnsrch; 2875 *domain && !done; 2876 domain++) { 2877 searched = 1; 2878 2879 if (domain[0][0] == '\0' || 2880 (domain[0][0] == '.' && domain[0][1] == '\0')) 2881 root_on_list++; 2882 2883 if (root_on_list && tried_as_is) 2884 continue; 2885 2886 ret = res_querydomainN(name, *domain, target, res); 2887 if (ret > 0) 2888 return (ret); 2889 2890 /* 2891 * If no server present, give up. 2892 * If name isn't found in this domain, 2893 * keep trying higher domains in the search list 2894 * (if that's enabled). 2895 * On a NO_DATA error, keep trying, otherwise 2896 * a wildcard entry of another type could keep us 2897 * from finding this entry higher in the domain. 2898 * If we get some other error (negative answer or 2899 * server failure), then stop searching up, 2900 * but try the input name below in case it's 2901 * fully-qualified. 2902 */ 2903 if (errno == ECONNREFUSED) { 2904 RES_SET_H_ERRNO(res, TRY_AGAIN); 2905 return (-1); 2906 } 2907 2908 switch (res->res_h_errno) { 2909 case NO_DATA: 2910 got_nodata++; 2911 /* FALLTHROUGH */ 2912 case HOST_NOT_FOUND: 2913 /* keep trying */ 2914 break; 2915 case TRY_AGAIN: 2916 got_servfail++; 2917 if (hp->rcode == SERVFAIL) { 2918 /* try next search element, if any */ 2919 break; 2920 } 2921 /* FALLTHROUGH */ 2922 default: 2923 /* anything else implies that we're done */ 2924 done++; 2925 } 2926 /* 2927 * if we got here for some reason other than DNSRCH, 2928 * we only wanted one iteration of the loop, so stop. 2929 */ 2930 if (!(res->options & RES_DNSRCH)) 2931 done++; 2932 } 2933 } 2934 2935 switch (res->res_h_errno) { 2936 case NO_DATA: 2937 case HOST_NOT_FOUND: 2938 break; 2939 case TRY_AGAIN: 2940 if (hp->rcode == SERVFAIL) 2941 break; 2942 /* FALLTHROUGH */ 2943 default: 2944 goto giveup; 2945 } 2946 2947 /* 2948 * If the query has not already been tried as is then try it 2949 * unless RES_NOTLDQUERY is set and there were no dots. 2950 */ 2951 if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) && 2952 !(tried_as_is || root_on_list)) { 2953 ret = res_querydomainN(name, NULL, target, res); 2954 if (ret > 0) 2955 return (ret); 2956 } 2957 2958 /* 2959 * if we got here, we didn't satisfy the search. 2960 * if we did an initial full query, return that query's h_errno 2961 * (note that we wouldn't be here if that query had succeeded). 2962 * else if we ever got a nodata, send that back as the reason. 2963 * else send back meaningless h_errno, that being the one from 2964 * the last DNSRCH we did. 2965 */ 2966giveup: 2967 if (saved_herrno != -1) 2968 RES_SET_H_ERRNO(res, saved_herrno); 2969 else if (got_nodata) 2970 RES_SET_H_ERRNO(res, NO_DATA); 2971 else if (got_servfail) 2972 RES_SET_H_ERRNO(res, TRY_AGAIN); 2973 return (-1); 2974} 2975 2976/* 2977 * Perform a call on res_query on the concatenation of name and domain, 2978 * removing a trailing dot from name if domain is NULL. 2979 */ 2980static int 2981res_querydomainN(const char *name, const char *domain, 2982 struct res_target *target, res_state res) 2983{ 2984 char nbuf[MAXDNAME]; 2985 const char *longname = nbuf; 2986 size_t n, d; 2987 2988#ifdef DEBUG 2989 if (res->options & RES_DEBUG) 2990 printf(";; res_querydomain(%s, %s)\n", 2991 name, domain?domain:"<Nil>"); 2992#endif 2993 if (domain == NULL) { 2994 /* 2995 * Check for trailing '.'; 2996 * copy without '.' if present. 2997 */ 2998 n = strlen(name); 2999 if (n >= MAXDNAME) { 3000 RES_SET_H_ERRNO(res, NO_RECOVERY); 3001 return (-1); 3002 } 3003 if (n > 0 && name[--n] == '.') { 3004 strncpy(nbuf, name, n); 3005 nbuf[n] = '\0'; 3006 } else 3007 longname = name; 3008 } else { 3009 n = strlen(name); 3010 d = strlen(domain); 3011 if (n + d + 1 >= MAXDNAME) { 3012 RES_SET_H_ERRNO(res, NO_RECOVERY); 3013 return (-1); 3014 } 3015 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 3016 } 3017 return (res_queryN(longname, target, res)); 3018} 3019