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