getaddrinfo.c revision 160593
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: head/lib/libc/net/getaddrinfo.c 160593 2006-07-23 15:31:03Z 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 <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 SUCCESS 0 106#define ANY 0 107#define YES 1 108#define NO 0 109 110static const char in_addrany[] = { 0, 0, 0, 0 }; 111static const char in_loopback[] = { 127, 0, 0, 1 }; 112#ifdef INET6 113static const char in6_addrany[] = { 114 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 115}; 116static const char in6_loopback[] = { 117 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 118}; 119#endif 120 121struct policyqueue { 122 TAILQ_ENTRY(policyqueue) pc_entry; 123#ifdef INET6 124 struct in6_addrpolicy pc_policy; 125#endif 126}; 127TAILQ_HEAD(policyhead, policyqueue); 128 129static const struct afd { 130 int a_af; 131 int a_addrlen; 132 socklen_t a_socklen; 133 int a_off; 134 const char *a_addrany; 135 const char *a_loopback; 136 int a_scoped; 137} afdl [] = { 138#ifdef INET6 139#define N_INET6 0 140 {PF_INET6, sizeof(struct in6_addr), 141 sizeof(struct sockaddr_in6), 142 offsetof(struct sockaddr_in6, sin6_addr), 143 in6_addrany, in6_loopback, 1}, 144#define N_INET 1 145#else 146#define N_INET 0 147#endif 148 {PF_INET, sizeof(struct in_addr), 149 sizeof(struct sockaddr_in), 150 offsetof(struct sockaddr_in, sin_addr), 151 in_addrany, in_loopback, 0}, 152 {0, 0, 0, 0, NULL, NULL, 0}, 153}; 154 155struct explore { 156 int e_af; 157 int e_socktype; 158 int e_protocol; 159 const char *e_protostr; 160 int e_wild; 161#define WILD_AF(ex) ((ex)->e_wild & 0x01) 162#define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 163#define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 164}; 165 166static const struct explore explore[] = { 167#if 0 168 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 169#endif 170#ifdef INET6 171 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 172 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 173 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 174#endif 175 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 176 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 177 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 178 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 179 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 180 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, 181 { -1, 0, 0, NULL, 0 }, 182}; 183 184#ifdef INET6 185#define PTON_MAX 16 186#else 187#define PTON_MAX 4 188#endif 189 190#define AIO_SRCFLAG_DEPRECATED 0x1 191 192struct ai_order { 193 union { 194 struct sockaddr_storage aiou_ss; 195 struct sockaddr aiou_sa; 196 } aio_src_un; 197#define aio_srcsa aio_src_un.aiou_sa 198 u_int32_t aio_srcflag; 199 int aio_srcscope; 200 int aio_dstscope; 201 struct policyqueue *aio_srcpolicy; 202 struct policyqueue *aio_dstpolicy; 203 struct addrinfo *aio_ai; 204 int aio_matchlen; 205}; 206 207static const ns_src default_dns_files[] = { 208 { NSSRC_FILES, NS_SUCCESS }, 209 { NSSRC_DNS, NS_SUCCESS }, 210 { 0 } 211}; 212 213struct res_target { 214 struct res_target *next; 215 const char *name; /* domain name */ 216 int qclass, qtype; /* class and type of query */ 217 u_char *answer; /* buffer to put answer */ 218 int anslen; /* size of answer buffer */ 219 int n; /* result length */ 220}; 221 222#define MAXPACKET (64*1024) 223 224typedef union { 225 HEADER hdr; 226 u_char buf[MAXPACKET]; 227} querybuf; 228 229static int str2number(const char *, int *); 230static int explore_null(const struct addrinfo *, 231 const char *, struct addrinfo **); 232static int explore_numeric(const struct addrinfo *, const char *, 233 const char *, struct addrinfo **, const char *); 234static int explore_numeric_scope(const struct addrinfo *, const char *, 235 const char *, struct addrinfo **); 236static int get_canonname(const struct addrinfo *, 237 struct addrinfo *, const char *); 238static struct addrinfo *get_ai(const struct addrinfo *, 239 const struct afd *, const char *); 240static int get_portmatch(const struct addrinfo *, const char *); 241static int get_port(struct addrinfo *, const char *, int); 242static const struct afd *find_afd(int); 243static int addrconfig(struct addrinfo *); 244static void set_source(struct ai_order *, struct policyhead *); 245static int comp_dst(const void *, const void *); 246#ifdef INET6 247static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 248#endif 249static int gai_addr2scopetype(struct sockaddr *); 250 251static int explore_fqdn(const struct addrinfo *, const char *, 252 const char *, struct addrinfo **); 253 254static int reorder(struct addrinfo *); 255static int get_addrselectpolicy(struct policyhead *); 256static void free_addrselectpolicy(struct policyhead *); 257static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 258 struct policyhead *); 259static int matchlen(struct sockaddr *, struct sockaddr *); 260 261static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 262 const struct addrinfo *, res_state); 263#if defined(RESOLVSORT) 264static int addr4sort(struct addrinfo *, res_state); 265#endif 266static int _dns_getaddrinfo(void *, void *, va_list); 267static void _sethtent(FILE **); 268static void _endhtent(FILE **); 269static struct addrinfo *_gethtent(FILE **, const char *, 270 const struct addrinfo *); 271static int _files_getaddrinfo(void *, void *, va_list); 272#ifdef YP 273static struct addrinfo *_yphostent(char *, const struct addrinfo *); 274static int _yp_getaddrinfo(void *, void *, va_list); 275#endif 276#ifdef NS_CACHING 277static int addrinfo_id_func(char *, size_t *, va_list, void *); 278static int addrinfo_marshal_func(char *, size_t *, void *, va_list, void *); 279static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, void *); 280#endif 281 282static int res_queryN(const char *, struct res_target *, res_state); 283static int res_searchN(const char *, struct res_target *, res_state); 284static int res_querydomainN(const char *, const char *, 285 struct res_target *, res_state); 286 287/* XXX macros that make external reference is BAD. */ 288 289#define GET_AI(ai, afd, addr) \ 290do { \ 291 /* external reference: pai, error, and label free */ \ 292 (ai) = get_ai(pai, (afd), (addr)); \ 293 if ((ai) == NULL) { \ 294 error = EAI_MEMORY; \ 295 goto free; \ 296 } \ 297} while (/*CONSTCOND*/0) 298 299#define GET_PORT(ai, serv) \ 300do { \ 301 /* external reference: error and label free */ \ 302 error = get_port((ai), (serv), 0); \ 303 if (error != 0) \ 304 goto free; \ 305} while (/*CONSTCOND*/0) 306 307#define GET_CANONNAME(ai, str) \ 308do { \ 309 /* external reference: pai, error and label free */ \ 310 error = get_canonname(pai, (ai), (str)); \ 311 if (error != 0) \ 312 goto free; \ 313} while (/*CONSTCOND*/0) 314 315#define ERR(err) \ 316do { \ 317 /* external reference: error, and label bad */ \ 318 error = (err); \ 319 goto bad; \ 320 /*NOTREACHED*/ \ 321} while (/*CONSTCOND*/0) 322 323#define MATCH_FAMILY(x, y, w) \ 324 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 325#define MATCH(x, y, w) \ 326 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 327 328void 329freeaddrinfo(struct addrinfo *ai) 330{ 331 struct addrinfo *next; 332 333 do { 334 next = ai->ai_next; 335 if (ai->ai_canonname) 336 free(ai->ai_canonname); 337 /* no need to free(ai->ai_addr) */ 338 free(ai); 339 ai = next; 340 } while (ai); 341} 342 343static int 344str2number(const char *p, int *portp) 345{ 346 char *ep; 347 unsigned long v; 348 349 if (*p == '\0') 350 return -1; 351 ep = NULL; 352 errno = 0; 353 v = strtoul(p, &ep, 10); 354 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) { 355 *portp = v; 356 return 0; 357 } else 358 return -1; 359} 360 361int 362getaddrinfo(const char *hostname, const char *servname, 363 const struct addrinfo *hints, struct addrinfo **res) 364{ 365 struct addrinfo sentinel; 366 struct addrinfo *cur; 367 int error = 0; 368 struct addrinfo ai; 369 struct addrinfo ai0; 370 struct addrinfo *pai; 371 const struct explore *ex; 372 int numeric = 0; 373 374 memset(&sentinel, 0, sizeof(sentinel)); 375 cur = &sentinel; 376 pai = &ai; 377 pai->ai_flags = 0; 378 pai->ai_family = PF_UNSPEC; 379 pai->ai_socktype = ANY; 380 pai->ai_protocol = ANY; 381 pai->ai_addrlen = 0; 382 pai->ai_canonname = NULL; 383 pai->ai_addr = NULL; 384 pai->ai_next = NULL; 385 386 if (hostname == NULL && servname == NULL) 387 return EAI_NONAME; 388 if (hints) { 389 /* error check for hints */ 390 if (hints->ai_addrlen || hints->ai_canonname || 391 hints->ai_addr || hints->ai_next) 392 ERR(EAI_BADHINTS); /* xxx */ 393 if (hints->ai_flags & ~AI_MASK) 394 ERR(EAI_BADFLAGS); 395 switch (hints->ai_family) { 396 case PF_UNSPEC: 397 case PF_INET: 398#ifdef INET6 399 case PF_INET6: 400#endif 401 break; 402 default: 403 ERR(EAI_FAMILY); 404 } 405 memcpy(pai, hints, sizeof(*pai)); 406 407 /* 408 * if both socktype/protocol are specified, check if they 409 * are meaningful combination. 410 */ 411 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 412 for (ex = explore; ex->e_af >= 0; ex++) { 413 if (pai->ai_family != ex->e_af) 414 continue; 415 if (ex->e_socktype == ANY) 416 continue; 417 if (ex->e_protocol == ANY) 418 continue; 419 if (pai->ai_socktype == ex->e_socktype && 420 pai->ai_protocol != ex->e_protocol) { 421 ERR(EAI_BADHINTS); 422 } 423 } 424 } 425 } 426 427 /* 428 * post-2553: AI_ALL and AI_V4MAPPED are effective only against 429 * AF_INET6 query. They need to be ignored if specified in other 430 * occassions. 431 */ 432 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 433 case AI_V4MAPPED: 434 case AI_ALL | AI_V4MAPPED: 435 if (pai->ai_family != AF_INET6) 436 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 437 break; 438 case AI_ALL: 439#if 1 440 /* illegal */ 441 ERR(EAI_BADFLAGS); 442#else 443 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 444#endif 445 break; 446 } 447 448 /* 449 * check for special cases. (1) numeric servname is disallowed if 450 * socktype/protocol are left unspecified. (2) servname is disallowed 451 * for raw and other inet{,6} sockets. 452 */ 453 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 454#ifdef PF_INET6 455 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 456#endif 457 ) { 458 ai0 = *pai; /* backup *pai */ 459 460 if (pai->ai_family == PF_UNSPEC) { 461#ifdef PF_INET6 462 pai->ai_family = PF_INET6; 463#else 464 pai->ai_family = PF_INET; 465#endif 466 } 467 error = get_portmatch(pai, servname); 468 if (error) 469 ERR(error); 470 471 *pai = ai0; 472 } 473 474 ai0 = *pai; 475 476 /* NULL hostname, or numeric hostname */ 477 for (ex = explore; ex->e_af >= 0; ex++) { 478 *pai = ai0; 479 480 /* PF_UNSPEC entries are prepared for DNS queries only */ 481 if (ex->e_af == PF_UNSPEC) 482 continue; 483 484 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 485 continue; 486 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 487 continue; 488 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 489 continue; 490 491 if (pai->ai_family == PF_UNSPEC) 492 pai->ai_family = ex->e_af; 493 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 494 pai->ai_socktype = ex->e_socktype; 495 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 496 pai->ai_protocol = ex->e_protocol; 497 498 if (hostname == NULL) 499 error = explore_null(pai, servname, &cur->ai_next); 500 else 501 error = explore_numeric_scope(pai, hostname, servname, 502 &cur->ai_next); 503 504 if (error) 505 goto free; 506 507 while (cur && cur->ai_next) 508 cur = cur->ai_next; 509 } 510 511 /* 512 * XXX 513 * If numreic representation of AF1 can be interpreted as FQDN 514 * representation of AF2, we need to think again about the code below. 515 */ 516 if (sentinel.ai_next) { 517 numeric = 1; 518 goto good; 519 } 520 521 if (hostname == NULL) 522 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 523 if (pai->ai_flags & AI_NUMERICHOST) 524 ERR(EAI_NONAME); 525 526 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 527 ERR(EAI_FAIL); 528 529 /* 530 * hostname as alphabetical name. 531 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 532 * outer loop by AFs. 533 */ 534 for (ex = explore; ex->e_af >= 0; ex++) { 535 *pai = ai0; 536 537 /* require exact match for family field */ 538 if (pai->ai_family != ex->e_af) 539 continue; 540 541 if (!MATCH(pai->ai_socktype, ex->e_socktype, 542 WILD_SOCKTYPE(ex))) { 543 continue; 544 } 545 if (!MATCH(pai->ai_protocol, ex->e_protocol, 546 WILD_PROTOCOL(ex))) { 547 continue; 548 } 549 550 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 551 pai->ai_socktype = ex->e_socktype; 552 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 553 pai->ai_protocol = ex->e_protocol; 554 555 error = explore_fqdn(pai, hostname, servname, 556 &cur->ai_next); 557 558 while (cur && cur->ai_next) 559 cur = cur->ai_next; 560 } 561 562 /* XXX inhibit errors if we have the result */ 563 if (sentinel.ai_next) 564 error = 0; 565 566good: 567 /* 568 * ensure we return either: 569 * - error == 0, non-NULL *res 570 * - error != 0, NULL *res 571 */ 572 if (error == 0) { 573 if (sentinel.ai_next) { 574 /* 575 * If the returned entry is for an active connection, 576 * and the given name is not numeric, reorder the 577 * list, so that the application would try the list 578 * in the most efficient order. 579 */ 580 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 581 if (!numeric) 582 (void)reorder(&sentinel); 583 } 584 *res = sentinel.ai_next; 585 return SUCCESS; 586 } else 587 error = EAI_FAIL; 588 } 589free: 590bad: 591 if (sentinel.ai_next) 592 freeaddrinfo(sentinel.ai_next); 593 *res = NULL; 594 return error; 595} 596 597static int 598reorder(struct addrinfo *sentinel) 599{ 600 struct addrinfo *ai, **aip; 601 struct ai_order *aio; 602 int i, n; 603 struct policyhead policyhead; 604 605 /* count the number of addrinfo elements for sorting. */ 606 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 607 ; 608 609 /* 610 * If the number is small enough, we can skip the reordering process. 611 */ 612 if (n <= 1) 613 return(n); 614 615 /* allocate a temporary array for sort and initialization of it. */ 616 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 617 return(n); /* give up reordering */ 618 memset(aio, 0, sizeof(*aio) * n); 619 620 /* retrieve address selection policy from the kernel */ 621 TAILQ_INIT(&policyhead); 622 if (!get_addrselectpolicy(&policyhead)) { 623 /* no policy is installed into kernel, we don't sort. */ 624 free(aio); 625 return (n); 626 } 627 628 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 629 aio[i].aio_ai = ai; 630 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 631 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 632 &policyhead); 633 set_source(&aio[i], &policyhead); 634 } 635 636 /* perform sorting. */ 637 qsort(aio, n, sizeof(*aio), comp_dst); 638 639 /* reorder the addrinfo chain. */ 640 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 641 *aip = aio[i].aio_ai; 642 aip = &aio[i].aio_ai->ai_next; 643 } 644 *aip = NULL; 645 646 /* cleanup and return */ 647 free(aio); 648 free_addrselectpolicy(&policyhead); 649 return(n); 650} 651 652static int 653get_addrselectpolicy(struct policyhead *head) 654{ 655#ifdef INET6 656 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 657 size_t l; 658 char *buf; 659 struct in6_addrpolicy *pol, *ep; 660 661 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 662 return (0); 663 if ((buf = malloc(l)) == NULL) 664 return (0); 665 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 666 free(buf); 667 return (0); 668 } 669 670 ep = (struct in6_addrpolicy *)(buf + l); 671 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 672 struct policyqueue *new; 673 674 if ((new = malloc(sizeof(*new))) == NULL) { 675 free_addrselectpolicy(head); /* make the list empty */ 676 break; 677 } 678 new->pc_policy = *pol; 679 TAILQ_INSERT_TAIL(head, new, pc_entry); 680 } 681 682 free(buf); 683 return (1); 684#else 685 return (0); 686#endif 687} 688 689static void 690free_addrselectpolicy(struct policyhead *head) 691{ 692 struct policyqueue *ent, *nent; 693 694 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 695 nent = TAILQ_NEXT(ent, pc_entry); 696 TAILQ_REMOVE(head, ent, pc_entry); 697 free(ent); 698 } 699} 700 701static struct policyqueue * 702match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 703{ 704#ifdef INET6 705 struct policyqueue *ent, *bestent = NULL; 706 struct in6_addrpolicy *pol; 707 int matchlen, bestmatchlen = -1; 708 u_char *mp, *ep, *k, *p, m; 709 struct sockaddr_in6 key; 710 711 switch(addr->sa_family) { 712 case AF_INET6: 713 key = *(struct sockaddr_in6 *)addr; 714 break; 715 case AF_INET: 716 /* convert the address into IPv4-mapped IPv6 address. */ 717 memset(&key, 0, sizeof(key)); 718 key.sin6_family = AF_INET6; 719 key.sin6_len = sizeof(key); 720 key.sin6_addr.s6_addr[10] = 0xff; 721 key.sin6_addr.s6_addr[11] = 0xff; 722 memcpy(&key.sin6_addr.s6_addr[12], 723 &((struct sockaddr_in *)addr)->sin_addr, 4); 724 break; 725 default: 726 return(NULL); 727 } 728 729 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 730 pol = &ent->pc_policy; 731 matchlen = 0; 732 733 mp = (u_char *)&pol->addrmask.sin6_addr; 734 ep = mp + 16; /* XXX: scope field? */ 735 k = (u_char *)&key.sin6_addr; 736 p = (u_char *)&pol->addr.sin6_addr; 737 for (; mp < ep && *mp; mp++, k++, p++) { 738 m = *mp; 739 if ((*k & m) != *p) 740 goto next; /* not match */ 741 if (m == 0xff) /* short cut for a typical case */ 742 matchlen += 8; 743 else { 744 while (m >= 0x80) { 745 matchlen++; 746 m <<= 1; 747 } 748 } 749 } 750 751 /* matched. check if this is better than the current best. */ 752 if (matchlen > bestmatchlen) { 753 bestent = ent; 754 bestmatchlen = matchlen; 755 } 756 757 next: 758 continue; 759 } 760 761 return(bestent); 762#else 763 return(NULL); 764#endif 765 766} 767 768static void 769set_source(struct ai_order *aio, struct policyhead *ph) 770{ 771 struct addrinfo ai = *aio->aio_ai; 772 struct sockaddr_storage ss; 773 socklen_t srclen; 774 int s; 775 776 /* set unspec ("no source is available"), just in case */ 777 aio->aio_srcsa.sa_family = AF_UNSPEC; 778 aio->aio_srcscope = -1; 779 780 switch(ai.ai_family) { 781 case AF_INET: 782#ifdef INET6 783 case AF_INET6: 784#endif 785 break; 786 default: /* ignore unsupported AFs explicitly */ 787 return; 788 } 789 790 /* XXX: make a dummy addrinfo to call connect() */ 791 ai.ai_socktype = SOCK_DGRAM; 792 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 793 ai.ai_next = NULL; 794 memset(&ss, 0, sizeof(ss)); 795 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 796 ai.ai_addr = (struct sockaddr *)&ss; 797 get_port(&ai, "1", 0); 798 799 /* open a socket to get the source address for the given dst */ 800 if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0) 801 return; /* give up */ 802 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 803 goto cleanup; 804 srclen = ai.ai_addrlen; 805 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 806 aio->aio_srcsa.sa_family = AF_UNSPEC; 807 goto cleanup; 808 } 809 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 810 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 811 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 812#ifdef INET6 813 if (ai.ai_family == AF_INET6) { 814 struct in6_ifreq ifr6; 815 u_int32_t flags6; 816 817 /* XXX: interface name should not be hardcoded */ 818 strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name)); 819 memset(&ifr6, 0, sizeof(ifr6)); 820 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 821 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 822 flags6 = ifr6.ifr_ifru.ifru_flags6; 823 if ((flags6 & IN6_IFF_DEPRECATED)) 824 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 825 } 826 } 827#endif 828 829 cleanup: 830 _close(s); 831 return; 832} 833 834static int 835matchlen(struct sockaddr *src, struct sockaddr *dst) 836{ 837 int match = 0; 838 u_char *s, *d; 839 u_char *lim, r; 840 int addrlen; 841 842 switch (src->sa_family) { 843#ifdef INET6 844 case AF_INET6: 845 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 846 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 847 addrlen = sizeof(struct in6_addr); 848 lim = s + addrlen; 849 break; 850#endif 851 case AF_INET: 852 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; 853 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; 854 addrlen = sizeof(struct in_addr); 855 lim = s + addrlen; 856 break; 857 default: 858 return(0); 859 } 860 861 while (s < lim) 862 if ((r = (*d++ ^ *s++)) != 0) { 863 while (r < addrlen * 8) { 864 match++; 865 r <<= 1; 866 } 867 break; 868 } else 869 match += 8; 870 return(match); 871} 872 873static int 874comp_dst(const void *arg1, const void *arg2) 875{ 876 const struct ai_order *dst1 = arg1, *dst2 = arg2; 877 878 /* 879 * Rule 1: Avoid unusable destinations. 880 * XXX: we currently do not consider if an appropriate route exists. 881 */ 882 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 883 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 884 return(-1); 885 } 886 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 887 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 888 return(1); 889 } 890 891 /* Rule 2: Prefer matching scope. */ 892 if (dst1->aio_dstscope == dst1->aio_srcscope && 893 dst2->aio_dstscope != dst2->aio_srcscope) { 894 return(-1); 895 } 896 if (dst1->aio_dstscope != dst1->aio_srcscope && 897 dst2->aio_dstscope == dst2->aio_srcscope) { 898 return(1); 899 } 900 901 /* Rule 3: Avoid deprecated addresses. */ 902 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 903 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 904 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 905 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 906 return(-1); 907 } 908 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 909 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 910 return(1); 911 } 912 } 913 914 /* Rule 4: Prefer home addresses. */ 915 /* XXX: not implemented yet */ 916 917 /* Rule 5: Prefer matching label. */ 918#ifdef INET6 919 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 920 dst1->aio_srcpolicy->pc_policy.label == 921 dst1->aio_dstpolicy->pc_policy.label && 922 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 923 dst2->aio_srcpolicy->pc_policy.label != 924 dst2->aio_dstpolicy->pc_policy.label)) { 925 return(-1); 926 } 927 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 928 dst2->aio_srcpolicy->pc_policy.label == 929 dst2->aio_dstpolicy->pc_policy.label && 930 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 931 dst1->aio_srcpolicy->pc_policy.label != 932 dst1->aio_dstpolicy->pc_policy.label)) { 933 return(1); 934 } 935#endif 936 937 /* Rule 6: Prefer higher precedence. */ 938#ifdef INET6 939 if (dst1->aio_dstpolicy && 940 (dst2->aio_dstpolicy == NULL || 941 dst1->aio_dstpolicy->pc_policy.preced > 942 dst2->aio_dstpolicy->pc_policy.preced)) { 943 return(-1); 944 } 945 if (dst2->aio_dstpolicy && 946 (dst1->aio_dstpolicy == NULL || 947 dst2->aio_dstpolicy->pc_policy.preced > 948 dst1->aio_dstpolicy->pc_policy.preced)) { 949 return(1); 950 } 951#endif 952 953 /* Rule 7: Prefer native transport. */ 954 /* XXX: not implemented yet */ 955 956 /* Rule 8: Prefer smaller scope. */ 957 if (dst1->aio_dstscope >= 0 && 958 dst1->aio_dstscope < dst2->aio_dstscope) { 959 return(-1); 960 } 961 if (dst2->aio_dstscope >= 0 && 962 dst2->aio_dstscope < dst1->aio_dstscope) { 963 return(1); 964 } 965 966 /* 967 * Rule 9: Use longest matching prefix. 968 * We compare the match length in a same AF only. 969 */ 970 if (dst1->aio_ai->ai_addr->sa_family == 971 dst2->aio_ai->ai_addr->sa_family) { 972 if (dst1->aio_matchlen > dst2->aio_matchlen) { 973 return(-1); 974 } 975 if (dst1->aio_matchlen < dst2->aio_matchlen) { 976 return(1); 977 } 978 } 979 980 /* Rule 10: Otherwise, leave the order unchanged. */ 981 return(-1); 982} 983 984/* 985 * Copy from scope.c. 986 * XXX: we should standardize the functions and link them as standard 987 * library. 988 */ 989static int 990gai_addr2scopetype(struct sockaddr *sa) 991{ 992#ifdef INET6 993 struct sockaddr_in6 *sa6; 994#endif 995 struct sockaddr_in *sa4; 996 997 switch(sa->sa_family) { 998#ifdef INET6 999 case AF_INET6: 1000 sa6 = (struct sockaddr_in6 *)sa; 1001 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1002 /* just use the scope field of the multicast address */ 1003 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1004 } 1005 /* 1006 * Unicast addresses: map scope type to corresponding scope 1007 * value defined for multcast addresses. 1008 * XXX: hardcoded scope type values are bad... 1009 */ 1010 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1011 return(1); /* node local scope */ 1012 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1013 return(2); /* link-local scope */ 1014 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1015 return(5); /* site-local scope */ 1016 return(14); /* global scope */ 1017 break; 1018#endif 1019 case AF_INET: 1020 /* 1021 * IPv4 pseudo scoping according to RFC 3484. 1022 */ 1023 sa4 = (struct sockaddr_in *)sa; 1024 /* IPv4 autoconfiguration addresses have link-local scope. */ 1025 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1026 ((u_char *)&sa4->sin_addr)[1] == 254) 1027 return(2); 1028 /* Private addresses have site-local scope. */ 1029 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1030 (((u_char *)&sa4->sin_addr)[0] == 172 && 1031 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1032 (((u_char *)&sa4->sin_addr)[0] == 192 && 1033 ((u_char *)&sa4->sin_addr)[1] == 168)) 1034 return(14); /* XXX: It should be 5 unless NAT */ 1035 /* Loopback addresses have link-local scope. */ 1036 if (((u_char *)&sa4->sin_addr)[0] == 127) 1037 return(2); 1038 return(14); 1039 break; 1040 default: 1041 errno = EAFNOSUPPORT; /* is this a good error? */ 1042 return(-1); 1043 } 1044} 1045 1046/* 1047 * hostname == NULL. 1048 * passive socket -> anyaddr (0.0.0.0 or ::) 1049 * non-passive socket -> localhost (127.0.0.1 or ::1) 1050 */ 1051static int 1052explore_null(const struct addrinfo *pai, const char *servname, 1053 struct addrinfo **res) 1054{ 1055 int s; 1056 const struct afd *afd; 1057 struct addrinfo *ai; 1058 int error; 1059 1060 *res = NULL; 1061 ai = NULL; 1062 1063 /* 1064 * filter out AFs that are not supported by the kernel 1065 * XXX errno? 1066 */ 1067 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1068 if (s < 0) { 1069 if (errno != EMFILE) 1070 return 0; 1071 } else 1072 _close(s); 1073 1074 /* 1075 * if the servname does not match socktype/protocol, ignore it. 1076 */ 1077 if (get_portmatch(pai, servname) != 0) 1078 return 0; 1079 1080 afd = find_afd(pai->ai_family); 1081 if (afd == NULL) 1082 return 0; 1083 1084 if (pai->ai_flags & AI_PASSIVE) { 1085 GET_AI(ai, afd, afd->a_addrany); 1086 GET_PORT(ai, servname); 1087 } else { 1088 GET_AI(ai, afd, afd->a_loopback); 1089 GET_PORT(ai, servname); 1090 } 1091 1092 *res = ai; 1093 return 0; 1094 1095free: 1096 if (ai != NULL) 1097 freeaddrinfo(ai); 1098 return error; 1099} 1100 1101/* 1102 * numeric hostname 1103 */ 1104static int 1105explore_numeric(const struct addrinfo *pai, const char *hostname, 1106 const char *servname, struct addrinfo **res, const char *canonname) 1107{ 1108 const struct afd *afd; 1109 struct addrinfo *ai; 1110 int error; 1111 char pton[PTON_MAX]; 1112 1113 *res = NULL; 1114 ai = NULL; 1115 1116 /* 1117 * if the servname does not match socktype/protocol, ignore it. 1118 */ 1119 if (get_portmatch(pai, servname) != 0) 1120 return 0; 1121 1122 afd = find_afd(pai->ai_family); 1123 if (afd == NULL) 1124 return 0; 1125 1126 switch (afd->a_af) { 1127 case AF_INET: 1128 /* 1129 * RFC3493 requires getaddrinfo() to accept AF_INET formats 1130 * that are accepted by inet_addr() and its family. The 1131 * accepted forms includes the "classful" one, which inet_pton 1132 * does not accept. So we need to separate the case for 1133 * AF_INET. 1134 */ 1135 if (inet_aton(hostname, (struct in_addr *)pton) != 1) 1136 return 0; 1137 break; 1138 default: 1139 if (inet_pton(afd->a_af, hostname, pton) != 1) 1140 return 0; 1141 break; 1142 } 1143 1144 if (pai->ai_family == afd->a_af) { 1145 GET_AI(ai, afd, pton); 1146 GET_PORT(ai, servname); 1147 if ((pai->ai_flags & AI_CANONNAME)) { 1148 /* 1149 * Set the numeric address itself as the canonical 1150 * name, based on a clarification in RFC3493. 1151 */ 1152 GET_CANONNAME(ai, canonname); 1153 } 1154 } else { 1155 /* 1156 * XXX: This should not happen since we already matched the AF 1157 * by find_afd. 1158 */ 1159 ERR(EAI_FAMILY); 1160 } 1161 1162 *res = ai; 1163 return 0; 1164 1165free: 1166bad: 1167 if (ai != NULL) 1168 freeaddrinfo(ai); 1169 return error; 1170} 1171 1172/* 1173 * numeric hostname with scope 1174 */ 1175static int 1176explore_numeric_scope(const struct addrinfo *pai, const char *hostname, 1177 const char *servname, struct addrinfo **res) 1178{ 1179#if !defined(SCOPE_DELIMITER) || !defined(INET6) 1180 return explore_numeric(pai, hostname, servname, res, hostname); 1181#else 1182 const struct afd *afd; 1183 struct addrinfo *cur; 1184 int error; 1185 char *cp, *hostname2 = NULL, *scope, *addr; 1186 struct sockaddr_in6 *sin6; 1187 1188 /* 1189 * if the servname does not match socktype/protocol, ignore it. 1190 */ 1191 if (get_portmatch(pai, servname) != 0) 1192 return 0; 1193 1194 afd = find_afd(pai->ai_family); 1195 if (afd == NULL) 1196 return 0; 1197 1198 if (!afd->a_scoped) 1199 return explore_numeric(pai, hostname, servname, res, hostname); 1200 1201 cp = strchr(hostname, SCOPE_DELIMITER); 1202 if (cp == NULL) 1203 return explore_numeric(pai, hostname, servname, res, hostname); 1204 1205 /* 1206 * Handle special case of <scoped_address><delimiter><scope id> 1207 */ 1208 hostname2 = strdup(hostname); 1209 if (hostname2 == NULL) 1210 return EAI_MEMORY; 1211 /* terminate at the delimiter */ 1212 hostname2[cp - hostname] = '\0'; 1213 addr = hostname2; 1214 scope = cp + 1; 1215 1216 error = explore_numeric(pai, addr, servname, res, hostname); 1217 if (error == 0) { 1218 u_int32_t scopeid; 1219 1220 for (cur = *res; cur; cur = cur->ai_next) { 1221 if (cur->ai_family != AF_INET6) 1222 continue; 1223 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1224 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1225 free(hostname2); 1226 return(EAI_NONAME); /* XXX: is return OK? */ 1227 } 1228 sin6->sin6_scope_id = scopeid; 1229 } 1230 } 1231 1232 free(hostname2); 1233 1234 return error; 1235#endif 1236} 1237 1238static int 1239get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) 1240{ 1241 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1242 ai->ai_canonname = strdup(str); 1243 if (ai->ai_canonname == NULL) 1244 return EAI_MEMORY; 1245 } 1246 return 0; 1247} 1248 1249static struct addrinfo * 1250get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) 1251{ 1252 char *p; 1253 struct addrinfo *ai; 1254#ifdef FAITH 1255 struct in6_addr faith_prefix; 1256 char *fp_str; 1257 int translate = 0; 1258#endif 1259 1260#ifdef FAITH 1261 /* 1262 * Transfrom an IPv4 addr into a special IPv6 addr format for 1263 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1264 * 1265 * +-----------------------------------+------------+ 1266 * | faith prefix part (12 bytes) | embedded | 1267 * | | IPv4 addr part (4 bytes) 1268 * +-----------------------------------+------------+ 1269 * 1270 * faith prefix part is specified as ascii IPv6 addr format 1271 * in environmental variable GAI. 1272 * For FAITH to work correctly, routing to faith prefix must be 1273 * setup toward a machine where a FAITH daemon operates. 1274 * Also, the machine must enable some mechanizm 1275 * (e.g. faith interface hack) to divert those packet with 1276 * faith prefixed destination addr to user-land FAITH daemon. 1277 */ 1278 fp_str = getenv("GAI"); 1279 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1280 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1281 u_int32_t v4a; 1282 u_int8_t v4a_top; 1283 1284 memcpy(&v4a, addr, sizeof v4a); 1285 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1286 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1287 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1288 afd = &afdl[N_INET6]; 1289 memcpy(&faith_prefix.s6_addr[12], addr, 1290 sizeof(struct in_addr)); 1291 translate = 1; 1292 } 1293 } 1294#endif 1295 1296 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1297 + (afd->a_socklen)); 1298 if (ai == NULL) 1299 return NULL; 1300 1301 memcpy(ai, pai, sizeof(struct addrinfo)); 1302 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1303 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1304 ai->ai_addr->sa_len = afd->a_socklen; 1305 ai->ai_addrlen = afd->a_socklen; 1306 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1307 p = (char *)(void *)(ai->ai_addr); 1308#ifdef FAITH 1309 if (translate == 1) 1310 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1311 else 1312#endif 1313 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1314 return ai; 1315} 1316 1317static int 1318get_portmatch(const struct addrinfo *ai, const char *servname) 1319{ 1320 1321 /* get_port does not touch first argument when matchonly == 1. */ 1322 /* LINTED const cast */ 1323 return get_port((struct addrinfo *)ai, servname, 1); 1324} 1325 1326static int 1327get_port(struct addrinfo *ai, const char *servname, int matchonly) 1328{ 1329 const char *proto; 1330 struct servent *sp; 1331 int port, error; 1332 int allownumeric; 1333 1334 if (servname == NULL) 1335 return 0; 1336 switch (ai->ai_family) { 1337 case AF_INET: 1338#ifdef AF_INET6 1339 case AF_INET6: 1340#endif 1341 break; 1342 default: 1343 return 0; 1344 } 1345 1346 switch (ai->ai_socktype) { 1347 case SOCK_RAW: 1348 return EAI_SERVICE; 1349 case SOCK_DGRAM: 1350 case SOCK_STREAM: 1351 allownumeric = 1; 1352 break; 1353 case ANY: 1354 allownumeric = 0; 1355 break; 1356 default: 1357 return EAI_SOCKTYPE; 1358 } 1359 1360 error = str2number(servname, &port); 1361 if (error == 0) { 1362 if (!allownumeric) 1363 return EAI_SERVICE; 1364 if (port < 0 || port > 65535) 1365 return EAI_SERVICE; 1366 port = htons(port); 1367 } else { 1368 if (ai->ai_flags & AI_NUMERICSERV) 1369 return EAI_NONAME; 1370 switch (ai->ai_socktype) { 1371 case SOCK_DGRAM: 1372 proto = "udp"; 1373 break; 1374 case SOCK_STREAM: 1375 proto = "tcp"; 1376 break; 1377 default: 1378 proto = NULL; 1379 break; 1380 } 1381 1382 if ((sp = getservbyname(servname, proto)) == NULL) 1383 return EAI_SERVICE; 1384 port = sp->s_port; 1385 } 1386 1387 if (!matchonly) { 1388 switch (ai->ai_family) { 1389 case AF_INET: 1390 ((struct sockaddr_in *)(void *) 1391 ai->ai_addr)->sin_port = port; 1392 break; 1393#ifdef INET6 1394 case AF_INET6: 1395 ((struct sockaddr_in6 *)(void *) 1396 ai->ai_addr)->sin6_port = port; 1397 break; 1398#endif 1399 } 1400 } 1401 1402 return 0; 1403} 1404 1405static const struct afd * 1406find_afd(int af) 1407{ 1408 const struct afd *afd; 1409 1410 if (af == PF_UNSPEC) 1411 return NULL; 1412 for (afd = afdl; afd->a_af; afd++) { 1413 if (afd->a_af == af) 1414 return afd; 1415 } 1416 return NULL; 1417} 1418 1419/* 1420 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1421 * will take care of it. 1422 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1423 * if the code is right or not. 1424 * 1425 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1426 * _dns_getaddrinfo. 1427 */ 1428static int 1429addrconfig(struct addrinfo *pai) 1430{ 1431 int s, af; 1432 1433 /* 1434 * TODO: 1435 * Note that implementation dependent test for address 1436 * configuration should be done everytime called 1437 * (or apropriate interval), 1438 * because addresses will be dynamically assigned or deleted. 1439 */ 1440 af = pai->ai_family; 1441 if (af == AF_UNSPEC) { 1442 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1443 af = AF_INET; 1444 else { 1445 _close(s); 1446 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1447 af = AF_INET6; 1448 else 1449 _close(s); 1450 } 1451 } 1452 if (af != AF_UNSPEC) { 1453 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1454 return 0; 1455 _close(s); 1456 } 1457 pai->ai_family = af; 1458 return 1; 1459} 1460 1461#ifdef INET6 1462/* convert a string to a scope identifier. XXX: IPv6 specific */ 1463static int 1464ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid) 1465{ 1466 u_long lscopeid; 1467 struct in6_addr *a6; 1468 char *ep; 1469 1470 a6 = &sin6->sin6_addr; 1471 1472 /* empty scopeid portion is invalid */ 1473 if (*scope == '\0') 1474 return -1; 1475 1476 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1477 /* 1478 * We currently assume a one-to-one mapping between links 1479 * and interfaces, so we simply use interface indices for 1480 * like-local scopes. 1481 */ 1482 *scopeid = if_nametoindex(scope); 1483 if (*scopeid == 0) 1484 goto trynumeric; 1485 return 0; 1486 } 1487 1488 /* still unclear about literal, allow numeric only - placeholder */ 1489 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1490 goto trynumeric; 1491 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1492 goto trynumeric; 1493 else 1494 goto trynumeric; /* global */ 1495 1496 /* try to convert to a numeric id as a last resort */ 1497 trynumeric: 1498 errno = 0; 1499 lscopeid = strtoul(scope, &ep, 10); 1500 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1501 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1502 return 0; 1503 else 1504 return -1; 1505} 1506#endif 1507 1508 1509#ifdef NS_CACHING 1510static int 1511addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap, 1512 void *cache_mdata) 1513{ 1514 res_state statp; 1515 u_long res_options; 1516 1517 const int op_id = 0; /* identifies the getaddrinfo for the cache */ 1518 char *hostname; 1519 struct addrinfo *hints; 1520 1521 char *p; 1522 int ai_flags, ai_family, ai_socktype, ai_protocol; 1523 size_t desired_size, size; 1524 1525 statp = __res_state(); 1526 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES | 1527 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6); 1528 1529 hostname = va_arg(ap, char *); 1530 hints = va_arg(ap, struct addrinfo *); 1531 1532 desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4; 1533 if (hostname != NULL) { 1534 size = strlen(hostname); 1535 desired_size += size + 1; 1536 } else 1537 size = 0; 1538 1539 if (desired_size > *buffer_size) { 1540 *buffer_size = desired_size; 1541 return (NS_RETURN); 1542 } 1543 1544 if (hints == NULL) 1545 ai_flags = ai_family = ai_socktype = ai_protocol = 0; 1546 else { 1547 ai_flags = hints->ai_flags; 1548 ai_family = hints->ai_family; 1549 ai_socktype = hints->ai_socktype; 1550 ai_protocol = hints->ai_protocol; 1551 } 1552 1553 p = buffer; 1554 memcpy(p, &res_options, sizeof(res_options)); 1555 p += sizeof(res_options); 1556 1557 memcpy(p, &op_id, sizeof(int)); 1558 p += sizeof(int); 1559 1560 memcpy(p, &ai_flags, sizeof(int)); 1561 p += sizeof(int); 1562 1563 memcpy(p, &ai_family, sizeof(int)); 1564 p += sizeof(int); 1565 1566 memcpy(p, &ai_socktype, sizeof(int)); 1567 p += sizeof(int); 1568 1569 memcpy(p, &ai_protocol, sizeof(int)); 1570 p += sizeof(int); 1571 1572 if (hostname != NULL) 1573 memcpy(p, hostname, size); 1574 1575 *buffer_size = desired_size; 1576 return (NS_SUCCESS); 1577} 1578 1579static int 1580addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval, 1581 va_list ap, void *cache_mdata) 1582{ 1583 struct addrinfo *ai, *cai; 1584 char *p; 1585 size_t desired_size, size, ai_size; 1586 1587 ai = *((struct addrinfo **)retval); 1588 1589 desired_size = sizeof(size_t); 1590 ai_size = 0; 1591 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1592 desired_size += sizeof(struct addrinfo) + cai->ai_addrlen; 1593 if (cai->ai_canonname != NULL) 1594 desired_size += sizeof(size_t) + 1595 strlen(cai->ai_canonname); 1596 ++ai_size; 1597 } 1598 1599 if (desired_size > *buffer_size) { 1600 /* this assignment is here for future use */ 1601 errno = ERANGE; 1602 *buffer_size = desired_size; 1603 return (NS_RETURN); 1604 } 1605 1606 memset(buffer, 0, desired_size); 1607 p = buffer; 1608 1609 memcpy(p, &ai_size, sizeof(size_t)); 1610 p += sizeof(size_t); 1611 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1612 memcpy(p, cai, sizeof(struct addrinfo)); 1613 p += sizeof(struct addrinfo); 1614 1615 memcpy(p, cai->ai_addr, cai->ai_addrlen); 1616 p += cai->ai_addrlen; 1617 1618 if (cai->ai_canonname != NULL) { 1619 size = strlen(cai->ai_canonname); 1620 memcpy(p, &size, sizeof(size_t)); 1621 p += sizeof(size_t); 1622 1623 memcpy(p, cai->ai_canonname, size); 1624 p += size; 1625 } 1626 } 1627 1628 return (NS_SUCCESS); 1629} 1630 1631static int 1632addrinfo_unmarshal_func(char *buffer, size_t buffer_size, void *retval, 1633 va_list ap, void *cache_mdata) 1634{ 1635 struct addrinfo new_ai, *result, *sentinel, *lasts; 1636 1637 char *p; 1638 size_t ai_size, ai_i, size; 1639 1640 p = buffer; 1641 memcpy(&ai_size, p, sizeof(size_t)); 1642 p += sizeof(size_t); 1643 1644 result = NULL; 1645 lasts = NULL; 1646 for (ai_i = 0; ai_i < ai_size; ++ai_i) { 1647 memcpy(&new_ai, p, sizeof(struct addrinfo)); 1648 p += sizeof(struct addrinfo); 1649 size = new_ai.ai_addrlen + sizeof(struct addrinfo) + 1650 _ALIGNBYTES; 1651 1652 sentinel = (struct addrinfo *)malloc(size); 1653 memset(sentinel, 0, size); 1654 1655 memcpy(sentinel, &new_ai, sizeof(struct addrinfo)); 1656 sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel + 1657 sizeof(struct addrinfo)); 1658 1659 memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen); 1660 p += new_ai.ai_addrlen; 1661 1662 if (new_ai.ai_canonname != NULL) { 1663 memcpy(&size, p, sizeof(size_t)); 1664 p += sizeof(size_t); 1665 1666 sentinel->ai_canonname = (char *)malloc(size + 1); 1667 memset(sentinel->ai_canonname, 0, size + 1); 1668 1669 memcpy(sentinel->ai_canonname, p, size); 1670 p += size; 1671 } 1672 1673 if (result == NULL) { 1674 result = sentinel; 1675 lasts = sentinel; 1676 } else { 1677 lasts->ai_next = sentinel; 1678 lasts = sentinel; 1679 } 1680 } 1681 1682 *((struct addrinfo **)retval) = result; 1683 return (NS_SUCCESS); 1684} 1685#endif /* NS_CACHING */ 1686 1687/* 1688 * FQDN hostname, DNS lookup 1689 */ 1690static int 1691explore_fqdn(const struct addrinfo *pai, const char *hostname, 1692 const char *servname, struct addrinfo **res) 1693{ 1694 struct addrinfo *result; 1695 struct addrinfo *cur; 1696 int error = 0; 1697 1698#ifdef NS_CACHING 1699 static const nss_cache_info cache_info = 1700 NS_COMMON_CACHE_INFO_INITIALIZER( 1701 hosts, NULL, addrinfo_id_func, addrinfo_marshal_func, 1702 addrinfo_unmarshal_func); 1703#endif 1704 static const ns_dtab dtab[] = { 1705 NS_FILES_CB(_files_getaddrinfo, NULL) 1706 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1707 NS_NIS_CB(_yp_getaddrinfo, NULL) 1708#ifdef NS_CACHING 1709 NS_CACHE_CB(&cache_info) 1710#endif 1711 { 0 } 1712 }; 1713 1714 result = NULL; 1715 1716 /* 1717 * if the servname does not match socktype/protocol, ignore it. 1718 */ 1719 if (get_portmatch(pai, servname) != 0) 1720 return 0; 1721 1722 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1723 default_dns_files, hostname, pai)) { 1724 case NS_TRYAGAIN: 1725 error = EAI_AGAIN; 1726 goto free; 1727 case NS_UNAVAIL: 1728 error = EAI_FAIL; 1729 goto free; 1730 case NS_NOTFOUND: 1731 error = EAI_NONAME; 1732 goto free; 1733 case NS_SUCCESS: 1734 error = 0; 1735 for (cur = result; cur; cur = cur->ai_next) { 1736 GET_PORT(cur, servname); 1737 /* canonname should be filled already */ 1738 } 1739 break; 1740 } 1741 1742 *res = result; 1743 1744 return 0; 1745 1746free: 1747 if (result) 1748 freeaddrinfo(result); 1749 return error; 1750} 1751 1752#ifdef DEBUG 1753static const char AskedForGot[] = 1754 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1755#endif 1756 1757static struct addrinfo * 1758getanswer(const querybuf *answer, int anslen, const char *qname, int qtype, 1759 const struct addrinfo *pai, res_state res) 1760{ 1761 struct addrinfo sentinel, *cur; 1762 struct addrinfo ai; 1763 const struct afd *afd; 1764 char *canonname; 1765 const HEADER *hp; 1766 const u_char *cp; 1767 int n; 1768 const u_char *eom; 1769 char *bp, *ep; 1770 int type, class, ancount, qdcount; 1771 int haveanswer, had_error; 1772 char tbuf[MAXDNAME]; 1773 int (*name_ok)(const char *); 1774 char hostbuf[8*1024]; 1775 1776 memset(&sentinel, 0, sizeof(sentinel)); 1777 cur = &sentinel; 1778 1779 canonname = NULL; 1780 eom = answer->buf + anslen; 1781 switch (qtype) { 1782 case T_A: 1783 case T_AAAA: 1784 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1785 name_ok = res_hnok; 1786 break; 1787 default: 1788 return (NULL); /* XXX should be abort(); */ 1789 } 1790 /* 1791 * find first satisfactory answer 1792 */ 1793 hp = &answer->hdr; 1794 ancount = ntohs(hp->ancount); 1795 qdcount = ntohs(hp->qdcount); 1796 bp = hostbuf; 1797 ep = hostbuf + sizeof hostbuf; 1798 cp = answer->buf + HFIXEDSZ; 1799 if (qdcount != 1) { 1800 RES_SET_H_ERRNO(res, NO_RECOVERY); 1801 return (NULL); 1802 } 1803 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1804 if ((n < 0) || !(*name_ok)(bp)) { 1805 RES_SET_H_ERRNO(res, NO_RECOVERY); 1806 return (NULL); 1807 } 1808 cp += n + QFIXEDSZ; 1809 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1810 /* res_send() has already verified that the query name is the 1811 * same as the one we sent; this just gets the expanded name 1812 * (i.e., with the succeeding search-domain tacked on). 1813 */ 1814 n = strlen(bp) + 1; /* for the \0 */ 1815 if (n >= MAXHOSTNAMELEN) { 1816 RES_SET_H_ERRNO(res, NO_RECOVERY); 1817 return (NULL); 1818 } 1819 canonname = bp; 1820 bp += n; 1821 /* The qname can be abbreviated, but h_name is now absolute. */ 1822 qname = canonname; 1823 } 1824 haveanswer = 0; 1825 had_error = 0; 1826 while (ancount-- > 0 && cp < eom && !had_error) { 1827 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1828 if ((n < 0) || !(*name_ok)(bp)) { 1829 had_error++; 1830 continue; 1831 } 1832 cp += n; /* name */ 1833 type = _getshort(cp); 1834 cp += INT16SZ; /* type */ 1835 class = _getshort(cp); 1836 cp += INT16SZ + INT32SZ; /* class, TTL */ 1837 n = _getshort(cp); 1838 cp += INT16SZ; /* len */ 1839 if (class != C_IN) { 1840 /* XXX - debug? syslog? */ 1841 cp += n; 1842 continue; /* XXX - had_error++ ? */ 1843 } 1844 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1845 type == T_CNAME) { 1846 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1847 if ((n < 0) || !(*name_ok)(tbuf)) { 1848 had_error++; 1849 continue; 1850 } 1851 cp += n; 1852 /* Get canonical name. */ 1853 n = strlen(tbuf) + 1; /* for the \0 */ 1854 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1855 had_error++; 1856 continue; 1857 } 1858 strlcpy(bp, tbuf, ep - bp); 1859 canonname = bp; 1860 bp += n; 1861 continue; 1862 } 1863 if (qtype == T_ANY) { 1864 if (!(type == T_A || type == T_AAAA)) { 1865 cp += n; 1866 continue; 1867 } 1868 } else if (type != qtype) { 1869#ifdef DEBUG 1870 if (type != T_KEY && type != T_SIG) 1871 syslog(LOG_NOTICE|LOG_AUTH, 1872 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1873 qname, p_class(C_IN), p_type(qtype), 1874 p_type(type)); 1875#endif 1876 cp += n; 1877 continue; /* XXX - had_error++ ? */ 1878 } 1879 switch (type) { 1880 case T_A: 1881 case T_AAAA: 1882 if (strcasecmp(canonname, bp) != 0) { 1883#ifdef DEBUG 1884 syslog(LOG_NOTICE|LOG_AUTH, 1885 AskedForGot, canonname, bp); 1886#endif 1887 cp += n; 1888 continue; /* XXX - had_error++ ? */ 1889 } 1890 if (type == T_A && n != INADDRSZ) { 1891 cp += n; 1892 continue; 1893 } 1894 if (type == T_AAAA && n != IN6ADDRSZ) { 1895 cp += n; 1896 continue; 1897 } 1898#ifdef FILTER_V4MAPPED 1899 if (type == T_AAAA) { 1900 struct in6_addr in6; 1901 memcpy(&in6, cp, sizeof(in6)); 1902 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1903 cp += n; 1904 continue; 1905 } 1906 } 1907#endif 1908 if (!haveanswer) { 1909 int nn; 1910 1911 canonname = bp; 1912 nn = strlen(bp) + 1; /* for the \0 */ 1913 bp += nn; 1914 } 1915 1916 /* don't overwrite pai */ 1917 ai = *pai; 1918 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1919 afd = find_afd(ai.ai_family); 1920 if (afd == NULL) { 1921 cp += n; 1922 continue; 1923 } 1924 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1925 if (cur->ai_next == NULL) 1926 had_error++; 1927 while (cur && cur->ai_next) 1928 cur = cur->ai_next; 1929 cp += n; 1930 break; 1931 default: 1932 abort(); 1933 } 1934 if (!had_error) 1935 haveanswer++; 1936 } 1937 if (haveanswer) { 1938#if defined(RESOLVSORT) 1939 /* 1940 * We support only IPv4 address for backward 1941 * compatibility against gethostbyname(3). 1942 */ 1943 if (res->nsort && qtype == T_A) { 1944 if (addr4sort(&sentinel, res) < 0) { 1945 freeaddrinfo(sentinel.ai_next); 1946 RES_SET_H_ERRNO(res, NO_RECOVERY); 1947 return NULL; 1948 } 1949 } 1950#endif /*RESOLVSORT*/ 1951 if (!canonname) 1952 (void)get_canonname(pai, sentinel.ai_next, qname); 1953 else 1954 (void)get_canonname(pai, sentinel.ai_next, canonname); 1955 RES_SET_H_ERRNO(res, NETDB_SUCCESS); 1956 return sentinel.ai_next; 1957 } 1958 1959 RES_SET_H_ERRNO(res, NO_RECOVERY); 1960 return NULL; 1961} 1962 1963#ifdef RESOLVSORT 1964struct addr_ptr { 1965 struct addrinfo *ai; 1966 int aval; 1967}; 1968 1969static int 1970addr4sort(struct addrinfo *sentinel, res_state res) 1971{ 1972 struct addrinfo *ai; 1973 struct addr_ptr *addrs, addr; 1974 struct sockaddr_in *sin; 1975 int naddrs, i, j; 1976 int needsort = 0; 1977 1978 if (!sentinel) 1979 return -1; 1980 naddrs = 0; 1981 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1982 naddrs++; 1983 if (naddrs < 2) 1984 return 0; /* We don't need sorting. */ 1985 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1986 return -1; 1987 i = 0; 1988 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1989 sin = (struct sockaddr_in *)ai->ai_addr; 1990 for (j = 0; (unsigned)j < res->nsort; j++) { 1991 if (res->sort_list[j].addr.s_addr == 1992 (sin->sin_addr.s_addr & res->sort_list[j].mask)) 1993 break; 1994 } 1995 addrs[i].ai = ai; 1996 addrs[i].aval = j; 1997 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1998 needsort = i; 1999 i++; 2000 } 2001 if (!needsort) { 2002 free(addrs); 2003 return 0; 2004 } 2005 2006 while (needsort < naddrs) { 2007 for (j = needsort - 1; j >= 0; j--) { 2008 if (addrs[j].aval > addrs[j+1].aval) { 2009 addr = addrs[j]; 2010 addrs[j] = addrs[j + 1]; 2011 addrs[j + 1] = addr; 2012 } else 2013 break; 2014 } 2015 needsort++; 2016 } 2017 2018 ai = sentinel; 2019 for (i = 0; i < naddrs; ++i) { 2020 ai->ai_next = addrs[i].ai; 2021 ai = ai->ai_next; 2022 } 2023 ai->ai_next = NULL; 2024 free(addrs); 2025 return 0; 2026} 2027#endif /*RESOLVSORT*/ 2028 2029/*ARGSUSED*/ 2030static int 2031_dns_getaddrinfo(void *rv, void *cb_data, va_list ap) 2032{ 2033 struct addrinfo *ai; 2034 querybuf *buf, *buf2; 2035 const char *hostname; 2036 const struct addrinfo *pai; 2037 struct addrinfo sentinel, *cur; 2038 struct res_target q, q2; 2039 res_state res; 2040 2041 hostname = va_arg(ap, char *); 2042 pai = va_arg(ap, const struct addrinfo *); 2043 2044 memset(&q, 0, sizeof(q)); 2045 memset(&q2, 0, sizeof(q2)); 2046 memset(&sentinel, 0, sizeof(sentinel)); 2047 cur = &sentinel; 2048 2049 buf = malloc(sizeof(*buf)); 2050 if (!buf) { 2051 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2052 return NS_NOTFOUND; 2053 } 2054 buf2 = malloc(sizeof(*buf2)); 2055 if (!buf2) { 2056 free(buf); 2057 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2058 return NS_NOTFOUND; 2059 } 2060 2061 switch (pai->ai_family) { 2062 case AF_UNSPEC: 2063 q.name = hostname; 2064 q.qclass = C_IN; 2065 q.qtype = T_A; 2066 q.answer = buf->buf; 2067 q.anslen = sizeof(buf->buf); 2068 q.next = &q2; 2069 q2.name = hostname; 2070 q2.qclass = C_IN; 2071 q2.qtype = T_AAAA; 2072 q2.answer = buf2->buf; 2073 q2.anslen = sizeof(buf2->buf); 2074 break; 2075 case AF_INET: 2076 q.name = hostname; 2077 q.qclass = C_IN; 2078 q.qtype = T_A; 2079 q.answer = buf->buf; 2080 q.anslen = sizeof(buf->buf); 2081 break; 2082 case AF_INET6: 2083 q.name = hostname; 2084 q.qclass = C_IN; 2085 q.qtype = T_AAAA; 2086 q.answer = buf->buf; 2087 q.anslen = sizeof(buf->buf); 2088 break; 2089 default: 2090 free(buf); 2091 free(buf2); 2092 return NS_UNAVAIL; 2093 } 2094 2095 res = __res_state(); 2096 if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) { 2097 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2098 free(buf); 2099 free(buf2); 2100 return NS_NOTFOUND; 2101 } 2102 2103 if (res_searchN(hostname, &q, res) < 0) { 2104 free(buf); 2105 free(buf2); 2106 return NS_NOTFOUND; 2107 } 2108 /* prefer IPv6 */ 2109 if (q.next) { 2110 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res); 2111 if (ai) { 2112 cur->ai_next = ai; 2113 while (cur && cur->ai_next) 2114 cur = cur->ai_next; 2115 } 2116 } 2117 ai = getanswer(buf, q.n, q.name, q.qtype, pai, res); 2118 if (ai) 2119 cur->ai_next = ai; 2120 free(buf); 2121 free(buf2); 2122 if (sentinel.ai_next == NULL) 2123 switch (res->res_h_errno) { 2124 case HOST_NOT_FOUND: 2125 return NS_NOTFOUND; 2126 case TRY_AGAIN: 2127 return NS_TRYAGAIN; 2128 default: 2129 return NS_UNAVAIL; 2130 } 2131 *((struct addrinfo **)rv) = sentinel.ai_next; 2132 return NS_SUCCESS; 2133} 2134 2135static void 2136_sethtent(FILE **hostf) 2137{ 2138 if (!*hostf) 2139 *hostf = fopen(_PATH_HOSTS, "r"); 2140 else 2141 rewind(*hostf); 2142} 2143 2144static void 2145_endhtent(FILE **hostf) 2146{ 2147 if (*hostf) { 2148 (void) fclose(*hostf); 2149 *hostf = NULL; 2150 } 2151} 2152 2153static struct addrinfo * 2154_gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2155{ 2156 char *p; 2157 char *cp, *tname, *cname; 2158 struct addrinfo hints, *res0, *res; 2159 int error; 2160 const char *addr; 2161 char hostbuf[8*1024]; 2162 2163 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "r"))) 2164 return (NULL); 2165again: 2166 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 2167 return (NULL); 2168 if (*p == '#') 2169 goto again; 2170 cp = strpbrk(p, "#\n"); 2171 if (cp != NULL) 2172 *cp = '\0'; 2173 if (!(cp = strpbrk(p, " \t"))) 2174 goto again; 2175 *cp++ = '\0'; 2176 addr = p; 2177 cname = NULL; 2178 /* if this is not something we're looking for, skip it. */ 2179 while (cp && *cp) { 2180 if (*cp == ' ' || *cp == '\t') { 2181 cp++; 2182 continue; 2183 } 2184 tname = cp; 2185 if (cname == NULL) 2186 cname = cp; 2187 if ((cp = strpbrk(cp, " \t")) != NULL) 2188 *cp++ = '\0'; 2189 if (strcasecmp(name, tname) == 0) 2190 goto found; 2191 } 2192 goto again; 2193 2194found: 2195 /* we should not glob socktype/protocol here */ 2196 memset(&hints, 0, sizeof(hints)); 2197 hints.ai_family = pai->ai_family; 2198 hints.ai_socktype = SOCK_DGRAM; 2199 hints.ai_protocol = 0; 2200 hints.ai_flags = AI_NUMERICHOST; 2201 error = getaddrinfo(addr, "0", &hints, &res0); 2202 if (error) 2203 goto again; 2204#ifdef FILTER_V4MAPPED 2205 /* XXX should check all items in the chain */ 2206 if (res0->ai_family == AF_INET6 && 2207 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2208 freeaddrinfo(res0); 2209 goto again; 2210 } 2211#endif 2212 for (res = res0; res; res = res->ai_next) { 2213 /* cover it up */ 2214 res->ai_flags = pai->ai_flags; 2215 res->ai_socktype = pai->ai_socktype; 2216 res->ai_protocol = pai->ai_protocol; 2217 2218 if (pai->ai_flags & AI_CANONNAME) { 2219 if (get_canonname(pai, res, cname) != 0) { 2220 freeaddrinfo(res0); 2221 goto again; 2222 } 2223 } 2224 } 2225 return res0; 2226} 2227 2228/*ARGSUSED*/ 2229static int 2230_files_getaddrinfo(void *rv, void *cb_data, va_list ap) 2231{ 2232 const char *name; 2233 const struct addrinfo *pai; 2234 struct addrinfo sentinel, *cur; 2235 struct addrinfo *p; 2236 FILE *hostf = NULL; 2237 2238 name = va_arg(ap, char *); 2239 pai = va_arg(ap, struct addrinfo *); 2240 2241 memset(&sentinel, 0, sizeof(sentinel)); 2242 cur = &sentinel; 2243 2244 _sethtent(&hostf); 2245 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2246 cur->ai_next = p; 2247 while (cur && cur->ai_next) 2248 cur = cur->ai_next; 2249 } 2250 _endhtent(&hostf); 2251 2252 *((struct addrinfo **)rv) = sentinel.ai_next; 2253 if (sentinel.ai_next == NULL) 2254 return NS_NOTFOUND; 2255 return NS_SUCCESS; 2256} 2257 2258#ifdef YP 2259/*ARGSUSED*/ 2260static struct addrinfo * 2261_yphostent(char *line, const struct addrinfo *pai) 2262{ 2263 struct addrinfo sentinel, *cur; 2264 struct addrinfo hints, *res, *res0; 2265 int error; 2266 char *p = line; 2267 const char *addr, *canonname; 2268 char *nextline; 2269 char *cp; 2270 2271 addr = canonname = NULL; 2272 2273 memset(&sentinel, 0, sizeof(sentinel)); 2274 cur = &sentinel; 2275 2276nextline: 2277 /* terminate line */ 2278 cp = strchr(p, '\n'); 2279 if (cp) { 2280 *cp++ = '\0'; 2281 nextline = cp; 2282 } else 2283 nextline = NULL; 2284 2285 cp = strpbrk(p, " \t"); 2286 if (cp == NULL) { 2287 if (canonname == NULL) 2288 return (NULL); 2289 else 2290 goto done; 2291 } 2292 *cp++ = '\0'; 2293 2294 addr = p; 2295 2296 while (cp && *cp) { 2297 if (*cp == ' ' || *cp == '\t') { 2298 cp++; 2299 continue; 2300 } 2301 if (!canonname) 2302 canonname = cp; 2303 if ((cp = strpbrk(cp, " \t")) != NULL) 2304 *cp++ = '\0'; 2305 } 2306 2307 hints = *pai; 2308 hints.ai_flags = AI_NUMERICHOST; 2309 error = getaddrinfo(addr, NULL, &hints, &res0); 2310 if (error == 0) { 2311 for (res = res0; res; res = res->ai_next) { 2312 /* cover it up */ 2313 res->ai_flags = pai->ai_flags; 2314 2315 if (pai->ai_flags & AI_CANONNAME) 2316 (void)get_canonname(pai, res, canonname); 2317 } 2318 } else 2319 res0 = NULL; 2320 if (res0) { 2321 cur->ai_next = res0; 2322 while (cur && cur->ai_next) 2323 cur = cur->ai_next; 2324 } 2325 2326 if (nextline) { 2327 p = nextline; 2328 goto nextline; 2329 } 2330 2331done: 2332 return sentinel.ai_next; 2333} 2334 2335/*ARGSUSED*/ 2336static int 2337_yp_getaddrinfo(void *rv, void *cb_data, va_list ap) 2338{ 2339 struct addrinfo sentinel, *cur; 2340 struct addrinfo *ai = NULL; 2341 char *ypbuf; 2342 int ypbuflen, r; 2343 const char *name; 2344 const struct addrinfo *pai; 2345 char *ypdomain; 2346 2347 if (_yp_check(&ypdomain) == 0) 2348 return NS_UNAVAIL; 2349 2350 name = va_arg(ap, char *); 2351 pai = va_arg(ap, const struct addrinfo *); 2352 2353 memset(&sentinel, 0, sizeof(sentinel)); 2354 cur = &sentinel; 2355 2356 /* hosts.byname is only for IPv4 (Solaris8) */ 2357 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2358 r = yp_match(ypdomain, "hosts.byname", name, 2359 (int)strlen(name), &ypbuf, &ypbuflen); 2360 if (r == 0) { 2361 struct addrinfo ai4; 2362 2363 ai4 = *pai; 2364 ai4.ai_family = AF_INET; 2365 ai = _yphostent(ypbuf, &ai4); 2366 if (ai) { 2367 cur->ai_next = ai; 2368 while (cur && cur->ai_next) 2369 cur = cur->ai_next; 2370 } 2371 free(ypbuf); 2372 } 2373 } 2374 2375 /* ipnodes.byname can hold both IPv4/v6 */ 2376 r = yp_match(ypdomain, "ipnodes.byname", name, 2377 (int)strlen(name), &ypbuf, &ypbuflen); 2378 if (r == 0) { 2379 ai = _yphostent(ypbuf, pai); 2380 if (ai) 2381 cur->ai_next = ai; 2382 free(ypbuf); 2383 } 2384 2385 if (sentinel.ai_next == NULL) { 2386 RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND); 2387 return NS_NOTFOUND; 2388 } 2389 *((struct addrinfo **)rv) = sentinel.ai_next; 2390 return NS_SUCCESS; 2391} 2392#endif 2393 2394/* resolver logic */ 2395 2396/* 2397 * Formulate a normal query, send, and await answer. 2398 * Returned answer is placed in supplied buffer "answer". 2399 * Perform preliminary check of answer, returning success only 2400 * if no error is indicated and the answer count is nonzero. 2401 * Return the size of the response on success, -1 on error. 2402 * Error number is left in h_errno. 2403 * 2404 * Caller must parse answer and determine whether it answers the question. 2405 */ 2406static int 2407res_queryN(const char *name, struct res_target *target, res_state res) 2408{ 2409 u_char *buf; 2410 HEADER *hp; 2411 int n; 2412 u_int oflags; 2413 struct res_target *t; 2414 int rcode; 2415 int ancount; 2416 2417 rcode = NOERROR; 2418 ancount = 0; 2419 2420 buf = malloc(MAXPACKET); 2421 if (!buf) { 2422 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2423 return -1; 2424 } 2425 2426 for (t = target; t; t = t->next) { 2427 int class, type; 2428 u_char *answer; 2429 int anslen; 2430 2431 hp = (HEADER *)(void *)t->answer; 2432 2433 /* make it easier... */ 2434 class = t->qclass; 2435 type = t->qtype; 2436 answer = t->answer; 2437 anslen = t->anslen; 2438 2439 oflags = res->_flags; 2440 2441again: 2442 hp->rcode = NOERROR; /* default */ 2443 2444#ifdef DEBUG 2445 if (res->options & RES_DEBUG) 2446 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2447#endif 2448 2449 n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL, 2450 buf, MAXPACKET); 2451 if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 && 2452 (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U) 2453 n = res_nopt(res, n, buf, MAXPACKET, anslen); 2454 if (n <= 0) { 2455#ifdef DEBUG 2456 if (res->options & RES_DEBUG) 2457 printf(";; res_query: mkquery failed\n"); 2458#endif 2459 free(buf); 2460 RES_SET_H_ERRNO(res, NO_RECOVERY); 2461 return (n); 2462 } 2463 n = res_nsend(res, buf, n, answer, anslen); 2464 if (n < 0) { 2465 /* 2466 * if the query choked with EDNS0, retry 2467 * without EDNS0 2468 */ 2469 if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) 2470 != 0U && 2471 ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) { 2472 res->_flags |= RES_F_EDNS0ERR; 2473 if (res->options & RES_DEBUG) 2474 printf(";; res_nquery: retry without EDNS0\n"); 2475 goto again; 2476 } 2477 rcode = hp->rcode; /* record most recent error */ 2478#ifdef DEBUG 2479 if (res->options & RES_DEBUG) 2480 printf(";; res_query: send error\n"); 2481#endif 2482 continue; 2483 } 2484 2485 if (n > anslen) 2486 hp->rcode = FORMERR; /* XXX not very informative */ 2487 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2488 rcode = hp->rcode; /* record most recent error */ 2489#ifdef DEBUG 2490 if (res->options & RES_DEBUG) 2491 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2492 ntohs(hp->ancount)); 2493#endif 2494 continue; 2495 } 2496 2497 ancount += ntohs(hp->ancount); 2498 2499 t->n = n; 2500 } 2501 2502 free(buf); 2503 2504 if (ancount == 0) { 2505 switch (rcode) { 2506 case NXDOMAIN: 2507 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); 2508 break; 2509 case SERVFAIL: 2510 RES_SET_H_ERRNO(res, TRY_AGAIN); 2511 break; 2512 case NOERROR: 2513 RES_SET_H_ERRNO(res, NO_DATA); 2514 break; 2515 case FORMERR: 2516 case NOTIMP: 2517 case REFUSED: 2518 default: 2519 RES_SET_H_ERRNO(res, NO_RECOVERY); 2520 break; 2521 } 2522 return (-1); 2523 } 2524 return (ancount); 2525} 2526 2527/* 2528 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2529 * Return the size of the response on success, -1 on error. 2530 * If enabled, implement search rules until answer or unrecoverable failure 2531 * is detected. Error code, if any, is left in h_errno. 2532 */ 2533static int 2534res_searchN(const char *name, struct res_target *target, res_state res) 2535{ 2536 const char *cp, * const *domain; 2537 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2538 u_int dots; 2539 int trailing_dot, ret, saved_herrno; 2540 int got_nodata = 0, got_servfail = 0, root_on_list = 0; 2541 int tried_as_is = 0; 2542 int searched = 0; 2543 char abuf[MAXDNAME]; 2544 2545 errno = 0; 2546 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */ 2547 dots = 0; 2548 for (cp = name; *cp; cp++) 2549 dots += (*cp == '.'); 2550 trailing_dot = 0; 2551 if (cp > name && *--cp == '.') 2552 trailing_dot++; 2553 2554 /* 2555 * if there aren't any dots, it could be a user-level alias 2556 */ 2557 if (!dots && 2558 (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL) 2559 return (res_queryN(cp, target, res)); 2560 2561 /* 2562 * If there are enough dots in the name, let's just give it a 2563 * try 'as is'. The threshold can be set with the "ndots" option. 2564 * Also, query 'as is', if there is a trailing dot in the name. 2565 */ 2566 saved_herrno = -1; 2567 if (dots >= res->ndots || trailing_dot) { 2568 ret = res_querydomainN(name, NULL, target, res); 2569 if (ret > 0 || trailing_dot) 2570 return (ret); 2571 if (errno == ECONNREFUSED) { 2572 RES_SET_H_ERRNO(res, TRY_AGAIN); 2573 return (-1); 2574 } 2575 switch (res->res_h_errno) { 2576 case NO_DATA: 2577 case HOST_NOT_FOUND: 2578 break; 2579 case TRY_AGAIN: 2580 if (hp->rcode == SERVFAIL) 2581 break; 2582 /* FALLTHROUGH */ 2583 default: 2584 return (-1); 2585 } 2586 saved_herrno = res->res_h_errno; 2587 tried_as_is++; 2588 } 2589 2590 /* 2591 * We do at least one level of search if 2592 * - there is no dot and RES_DEFNAME is set, or 2593 * - there is at least one dot, there is no trailing dot, 2594 * and RES_DNSRCH is set. 2595 */ 2596 if ((!dots && (res->options & RES_DEFNAMES)) || 2597 (dots && !trailing_dot && (res->options & RES_DNSRCH))) { 2598 int done = 0; 2599 2600 for (domain = (const char * const *)res->dnsrch; 2601 *domain && !done; 2602 domain++) { 2603 searched = 1; 2604 2605 if (domain[0][0] == '\0' || 2606 (domain[0][0] == '.' && domain[0][1] == '\0')) 2607 root_on_list++; 2608 2609 if (root_on_list && tried_as_is) 2610 continue; 2611 2612 ret = res_querydomainN(name, *domain, target, res); 2613 if (ret > 0) 2614 return (ret); 2615 2616 /* 2617 * If no server present, give up. 2618 * If name isn't found in this domain, 2619 * keep trying higher domains in the search list 2620 * (if that's enabled). 2621 * On a NO_DATA error, keep trying, otherwise 2622 * a wildcard entry of another type could keep us 2623 * from finding this entry higher in the domain. 2624 * If we get some other error (negative answer or 2625 * server failure), then stop searching up, 2626 * but try the input name below in case it's 2627 * fully-qualified. 2628 */ 2629 if (errno == ECONNREFUSED) { 2630 RES_SET_H_ERRNO(res, TRY_AGAIN); 2631 return (-1); 2632 } 2633 2634 switch (res->res_h_errno) { 2635 case NO_DATA: 2636 got_nodata++; 2637 /* FALLTHROUGH */ 2638 case HOST_NOT_FOUND: 2639 /* keep trying */ 2640 break; 2641 case TRY_AGAIN: 2642 got_servfail++; 2643 if (hp->rcode == SERVFAIL) { 2644 /* try next search element, if any */ 2645 break; 2646 } 2647 /* FALLTHROUGH */ 2648 default: 2649 /* anything else implies that we're done */ 2650 done++; 2651 } 2652 /* 2653 * if we got here for some reason other than DNSRCH, 2654 * we only wanted one iteration of the loop, so stop. 2655 */ 2656 if (!(res->options & RES_DNSRCH)) 2657 done++; 2658 } 2659 } 2660 2661 switch (res->res_h_errno) { 2662 case NO_DATA: 2663 case HOST_NOT_FOUND: 2664 break; 2665 case TRY_AGAIN: 2666 if (hp->rcode == SERVFAIL) 2667 break; 2668 /* FALLTHROUGH */ 2669 default: 2670 goto giveup; 2671 } 2672 2673 /* 2674 * If the query has not already been tried as is then try it 2675 * unless RES_NOTLDQUERY is set and there were no dots. 2676 */ 2677 if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) && 2678 !(tried_as_is || root_on_list)) { 2679 ret = res_querydomainN(name, NULL, target, res); 2680 if (ret > 0) 2681 return (ret); 2682 } 2683 2684 /* 2685 * if we got here, we didn't satisfy the search. 2686 * if we did an initial full query, return that query's h_errno 2687 * (note that we wouldn't be here if that query had succeeded). 2688 * else if we ever got a nodata, send that back as the reason. 2689 * else send back meaningless h_errno, that being the one from 2690 * the last DNSRCH we did. 2691 */ 2692giveup: 2693 if (saved_herrno != -1) 2694 RES_SET_H_ERRNO(res, saved_herrno); 2695 else if (got_nodata) 2696 RES_SET_H_ERRNO(res, NO_DATA); 2697 else if (got_servfail) 2698 RES_SET_H_ERRNO(res, TRY_AGAIN); 2699 return (-1); 2700} 2701 2702/* 2703 * Perform a call on res_query on the concatenation of name and domain, 2704 * removing a trailing dot from name if domain is NULL. 2705 */ 2706static int 2707res_querydomainN(const char *name, const char *domain, 2708 struct res_target *target, res_state res) 2709{ 2710 char nbuf[MAXDNAME]; 2711 const char *longname = nbuf; 2712 size_t n, d; 2713 2714#ifdef DEBUG 2715 if (res->options & RES_DEBUG) 2716 printf(";; res_querydomain(%s, %s)\n", 2717 name, domain?domain:"<Nil>"); 2718#endif 2719 if (domain == NULL) { 2720 /* 2721 * Check for trailing '.'; 2722 * copy without '.' if present. 2723 */ 2724 n = strlen(name); 2725 if (n >= MAXDNAME) { 2726 RES_SET_H_ERRNO(res, NO_RECOVERY); 2727 return (-1); 2728 } 2729 if (n > 0 && name[--n] == '.') { 2730 strncpy(nbuf, name, n); 2731 nbuf[n] = '\0'; 2732 } else 2733 longname = name; 2734 } else { 2735 n = strlen(name); 2736 d = strlen(domain); 2737 if (n + d + 1 >= MAXDNAME) { 2738 RES_SET_H_ERRNO(res, NO_RECOVERY); 2739 return (-1); 2740 } 2741 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2742 } 2743 return (res_queryN(longname, target, res)); 2744} 2745