getaddrinfo.c revision 146244
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 * - Thread safe-ness must be checked. 37 * - Return values. There are nonstandard return values defined and used 38 * in the source code. This is because RFC2553 is silent about which error 39 * code must be returned for which situation. 40 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 41 * invalid. current code - SEGV on freeaddrinfo(NULL) 42 * 43 * Note: 44 * - The code filters out AFs that are not supported by the kernel, 45 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 46 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 47 * in ai_flags? 48 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 49 * (1) what should we do against numeric hostname (2) what should we do 50 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 51 * non-loopback address configured? global address configured? 52 * 53 * OS specific notes for netbsd/openbsd/freebsd4/bsdi4: 54 * - To avoid search order issue, we have a big amount of code duplicate 55 * from gethnamaddr.c and some other places. The issues that there's no 56 * lower layer function to lookup "IPv4 or IPv6" record. Calling 57 * gethostbyname2 from getaddrinfo will end up in wrong search order, as 58 * presented above. 59 * 60 * OS specific notes for freebsd4: 61 * - FreeBSD supported $GAI. The code does not. 62 * - FreeBSD allowed classful IPv4 numeric (127.1), the code does not. 63 */ 64 65#include <sys/cdefs.h> 66__FBSDID("$FreeBSD: head/lib/libc/net/getaddrinfo.c 146244 2005-05-15 20:15:15Z ume $"); 67 68#include "namespace.h" 69#include <sys/types.h> 70#include <sys/param.h> 71#include <sys/socket.h> 72#include <net/if.h> 73#include <netinet/in.h> 74#include <sys/queue.h> 75#ifdef INET6 76#include <net/if_var.h> 77#include <sys/sysctl.h> 78#include <sys/ioctl.h> 79#include <netinet6/in6_var.h> /* XXX */ 80#endif 81#include <arpa/inet.h> 82#include <arpa/nameser.h> 83#include <rpc/rpc.h> 84#include <rpcsvc/yp_prot.h> 85#include <rpcsvc/ypclnt.h> 86#include <netdb.h> 87#include <resolv.h> 88#include <string.h> 89#include <stdlib.h> 90#include <stddef.h> 91#include <ctype.h> 92#include <unistd.h> 93#include <stdio.h> 94#include <errno.h> 95 96#include "res_config.h" 97 98#ifdef DEBUG 99#include <syslog.h> 100#endif 101 102#include <stdarg.h> 103#include <nsswitch.h> 104#include "un-namespace.h" 105#include "libc_private.h" 106 107#if defined(__KAME__) && defined(INET6) 108# define FAITH 109#endif 110 111#define SUCCESS 0 112#define ANY 0 113#define YES 1 114#define NO 0 115 116static const char in_addrany[] = { 0, 0, 0, 0 }; 117static const char in_loopback[] = { 127, 0, 0, 1 }; 118#ifdef INET6 119static const char in6_addrany[] = { 120 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 121}; 122static const char in6_loopback[] = { 123 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 124}; 125#endif 126 127struct policyqueue { 128 TAILQ_ENTRY(policyqueue) pc_entry; 129#ifdef INET6 130 struct in6_addrpolicy pc_policy; 131#endif 132}; 133TAILQ_HEAD(policyhead, policyqueue); 134 135static const struct afd { 136 int a_af; 137 int a_addrlen; 138 socklen_t a_socklen; 139 int a_off; 140 const char *a_addrany; 141 const char *a_loopback; 142 int a_scoped; 143} afdl [] = { 144#ifdef INET6 145#define N_INET6 0 146 {PF_INET6, sizeof(struct in6_addr), 147 sizeof(struct sockaddr_in6), 148 offsetof(struct sockaddr_in6, sin6_addr), 149 in6_addrany, in6_loopback, 1}, 150#define N_INET 1 151#else 152#define N_INET 0 153#endif 154 {PF_INET, sizeof(struct in_addr), 155 sizeof(struct sockaddr_in), 156 offsetof(struct sockaddr_in, sin_addr), 157 in_addrany, in_loopback, 0}, 158 {0, 0, 0, 0, NULL, NULL, 0}, 159}; 160 161struct explore { 162 int e_af; 163 int e_socktype; 164 int e_protocol; 165 const char *e_protostr; 166 int e_wild; 167#define WILD_AF(ex) ((ex)->e_wild & 0x01) 168#define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 169#define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 170}; 171 172static const struct explore explore[] = { 173#if 0 174 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 175#endif 176#ifdef INET6 177 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 178 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 179 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 180#endif 181 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 182 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 183 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 184 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 185 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 186 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, 187 { -1, 0, 0, NULL, 0 }, 188}; 189 190#ifdef INET6 191#define PTON_MAX 16 192#else 193#define PTON_MAX 4 194#endif 195 196#define AIO_SRCFLAG_DEPRECATED 0x1 197 198struct ai_order { 199 union { 200 struct sockaddr_storage aiou_ss; 201 struct sockaddr aiou_sa; 202 } aio_src_un; 203#define aio_srcsa aio_src_un.aiou_sa 204 u_int32_t aio_srcflag; 205 int aio_srcscope; 206 int aio_dstscope; 207 struct policyqueue *aio_srcpolicy; 208 struct policyqueue *aio_dstpolicy; 209 struct addrinfo *aio_ai; 210 int aio_matchlen; 211}; 212 213static const ns_src default_dns_files[] = { 214 { NSSRC_FILES, NS_SUCCESS }, 215 { NSSRC_DNS, NS_SUCCESS }, 216 { 0 } 217}; 218 219struct res_target { 220 struct res_target *next; 221 const char *name; /* domain name */ 222 int qclass, qtype; /* class and type of query */ 223 u_char *answer; /* buffer to put answer */ 224 int anslen; /* size of answer buffer */ 225 int n; /* result length */ 226}; 227 228#define MAXPACKET (64*1024) 229 230typedef union { 231 HEADER hdr; 232 u_char buf[MAXPACKET]; 233} querybuf; 234 235static int str2number(const char *); 236static int explore_null(const struct addrinfo *, 237 const char *, struct addrinfo **); 238static int explore_numeric(const struct addrinfo *, const char *, 239 const char *, struct addrinfo **, const char *); 240static int explore_numeric_scope(const struct addrinfo *, const char *, 241 const char *, struct addrinfo **); 242static int get_canonname(const struct addrinfo *, 243 struct addrinfo *, const char *); 244static struct addrinfo *get_ai(const struct addrinfo *, 245 const struct afd *, const char *); 246static int get_portmatch(const struct addrinfo *, const char *); 247static int get_port(struct addrinfo *, const char *, int); 248static const struct afd *find_afd(int); 249static int addrconfig(struct addrinfo *); 250static void set_source(struct ai_order *, struct policyhead *); 251static int comp_dst(const void *, const void *); 252#ifdef INET6 253static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 254#endif 255static int gai_addr2scopetype(struct sockaddr *); 256 257static int explore_fqdn(const struct addrinfo *, const char *, 258 const char *, struct addrinfo **); 259 260static int reorder(struct addrinfo *); 261static int get_addrselectpolicy(struct policyhead *); 262static void free_addrselectpolicy(struct policyhead *); 263static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 264 struct policyhead *); 265static int matchlen(struct sockaddr *, struct sockaddr *); 266 267static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 268 const struct addrinfo *); 269#if defined(RESOLVSORT) 270static int addr4sort(struct addrinfo *); 271#endif 272static int _dns_getaddrinfo(void *, void *, va_list); 273static void _sethtent(FILE **); 274static void _endhtent(FILE **); 275static struct addrinfo *_gethtent(FILE **, const char *, 276 const struct addrinfo *); 277static int _files_getaddrinfo(void *, void *, va_list); 278#ifdef YP 279static struct addrinfo *_yphostent(char *, const struct addrinfo *); 280static int _yp_getaddrinfo(void *, void *, va_list); 281#endif 282 283static int res_queryN(const char *, struct res_target *); 284static int res_searchN(const char *, struct res_target *); 285static int res_querydomainN(const char *, const char *, 286 struct res_target *); 287 288/* XXX macros that make external reference is BAD. */ 289 290#define GET_AI(ai, afd, addr) \ 291do { \ 292 /* external reference: pai, error, and label free */ \ 293 (ai) = get_ai(pai, (afd), (addr)); \ 294 if ((ai) == NULL) { \ 295 error = EAI_MEMORY; \ 296 goto free; \ 297 } \ 298} while (/*CONSTCOND*/0) 299 300#define GET_PORT(ai, serv) \ 301do { \ 302 /* external reference: error and label free */ \ 303 error = get_port((ai), (serv), 0); \ 304 if (error != 0) \ 305 goto free; \ 306} while (/*CONSTCOND*/0) 307 308#define GET_CANONNAME(ai, str) \ 309do { \ 310 /* external reference: pai, error and label free */ \ 311 error = get_canonname(pai, (ai), (str)); \ 312 if (error != 0) \ 313 goto free; \ 314} while (/*CONSTCOND*/0) 315 316#define ERR(err) \ 317do { \ 318 /* external reference: error, and label bad */ \ 319 error = (err); \ 320 goto bad; \ 321 /*NOTREACHED*/ \ 322} while (/*CONSTCOND*/0) 323 324#define MATCH_FAMILY(x, y, w) \ 325 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 326#define MATCH(x, y, w) \ 327 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 328 329void 330freeaddrinfo(ai) 331 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(p) 347 const char *p; 348{ 349 char *ep; 350 unsigned long v; 351 352 if (*p == '\0') 353 return -1; 354 ep = NULL; 355 errno = 0; 356 v = strtoul(p, &ep, 10); 357 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) 358 return v; 359 else 360 return -1; 361} 362 363int 364getaddrinfo(hostname, servname, hints, res) 365 const char *hostname, *servname; 366 const struct addrinfo *hints; 367 struct addrinfo **res; 368{ 369 struct addrinfo sentinel; 370 struct addrinfo *cur; 371 int error = 0; 372 struct addrinfo ai; 373 struct addrinfo ai0; 374 struct addrinfo *pai; 375 const struct explore *ex; 376 int numeric = 0; 377 378 memset(&sentinel, 0, sizeof(sentinel)); 379 cur = &sentinel; 380 pai = &ai; 381 pai->ai_flags = 0; 382 pai->ai_family = PF_UNSPEC; 383 pai->ai_socktype = ANY; 384 pai->ai_protocol = ANY; 385 pai->ai_addrlen = 0; 386 pai->ai_canonname = NULL; 387 pai->ai_addr = NULL; 388 pai->ai_next = NULL; 389 390 if (hostname == NULL && servname == NULL) 391 return EAI_NONAME; 392 if (hints) { 393 /* error check for hints */ 394 if (hints->ai_addrlen || hints->ai_canonname || 395 hints->ai_addr || hints->ai_next) 396 ERR(EAI_BADHINTS); /* xxx */ 397 if (hints->ai_flags & ~AI_MASK) 398 ERR(EAI_BADFLAGS); 399 switch (hints->ai_family) { 400 case PF_UNSPEC: 401 case PF_INET: 402#ifdef INET6 403 case PF_INET6: 404#endif 405 break; 406 default: 407 ERR(EAI_FAMILY); 408 } 409 memcpy(pai, hints, sizeof(*pai)); 410 411 /* 412 * if both socktype/protocol are specified, check if they 413 * are meaningful combination. 414 */ 415 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 416 for (ex = explore; ex->e_af >= 0; ex++) { 417 if (pai->ai_family != ex->e_af) 418 continue; 419 if (ex->e_socktype == ANY) 420 continue; 421 if (ex->e_protocol == ANY) 422 continue; 423 if (pai->ai_socktype == ex->e_socktype && 424 pai->ai_protocol != ex->e_protocol) { 425 ERR(EAI_BADHINTS); 426 } 427 } 428 } 429 } 430 431 /* 432 * post-2553: AI_ALL and AI_V4MAPPED are effective only against 433 * AF_INET6 query. They need to be ignored if specified in other 434 * occassions. 435 */ 436 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 437 case AI_V4MAPPED: 438 case AI_ALL | AI_V4MAPPED: 439 if (pai->ai_family != AF_INET6) 440 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 441 break; 442 case AI_ALL: 443#if 1 444 /* illegal */ 445 ERR(EAI_BADFLAGS); 446#else 447 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 448#endif 449 break; 450 } 451 452 /* 453 * check for special cases. (1) numeric servname is disallowed if 454 * socktype/protocol are left unspecified. (2) servname is disallowed 455 * for raw and other inet{,6} sockets. 456 */ 457 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 458#ifdef PF_INET6 459 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 460#endif 461 ) { 462 ai0 = *pai; /* backup *pai */ 463 464 if (pai->ai_family == PF_UNSPEC) { 465#ifdef PF_INET6 466 pai->ai_family = PF_INET6; 467#else 468 pai->ai_family = PF_INET; 469#endif 470 } 471 error = get_portmatch(pai, servname); 472 if (error) 473 ERR(error); 474 475 *pai = ai0; 476 } 477 478 ai0 = *pai; 479 480 /* NULL hostname, or numeric hostname */ 481 for (ex = explore; ex->e_af >= 0; ex++) { 482 *pai = ai0; 483 484 /* PF_UNSPEC entries are prepared for DNS queries only */ 485 if (ex->e_af == PF_UNSPEC) 486 continue; 487 488 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 489 continue; 490 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 491 continue; 492 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 493 continue; 494 495 if (pai->ai_family == PF_UNSPEC) 496 pai->ai_family = ex->e_af; 497 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 498 pai->ai_socktype = ex->e_socktype; 499 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 500 pai->ai_protocol = ex->e_protocol; 501 502 if (hostname == NULL) 503 error = explore_null(pai, servname, &cur->ai_next); 504 else 505 error = explore_numeric_scope(pai, hostname, servname, 506 &cur->ai_next); 507 508 if (error) 509 goto free; 510 511 while (cur && cur->ai_next) 512 cur = cur->ai_next; 513 } 514 515 /* 516 * XXX 517 * If numreic representation of AF1 can be interpreted as FQDN 518 * representation of AF2, we need to think again about the code below. 519 */ 520 if (sentinel.ai_next) { 521 numeric = 1; 522 goto good; 523 } 524 525 if (hostname == NULL) 526 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 527 if (pai->ai_flags & AI_NUMERICHOST) 528 ERR(EAI_NONAME); 529 530 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 531 ERR(EAI_FAIL); 532 533 /* 534 * hostname as alphabetical name. 535 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 536 * outer loop by AFs. 537 */ 538 for (ex = explore; ex->e_af >= 0; ex++) { 539 *pai = ai0; 540 541 /* require exact match for family field */ 542 if (pai->ai_family != ex->e_af) 543 continue; 544 545 if (!MATCH(pai->ai_socktype, ex->e_socktype, 546 WILD_SOCKTYPE(ex))) { 547 continue; 548 } 549 if (!MATCH(pai->ai_protocol, ex->e_protocol, 550 WILD_PROTOCOL(ex))) { 551 continue; 552 } 553 554 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 555 pai->ai_socktype = ex->e_socktype; 556 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 557 pai->ai_protocol = ex->e_protocol; 558 559 error = explore_fqdn(pai, hostname, servname, 560 &cur->ai_next); 561 562 while (cur && cur->ai_next) 563 cur = cur->ai_next; 564 } 565 566 /* XXX inhibit errors if we have the result */ 567 if (sentinel.ai_next) 568 error = 0; 569 570good: 571 /* 572 * ensure we return either: 573 * - error == 0, non-NULL *res 574 * - error != 0, NULL *res 575 */ 576 if (error == 0) { 577 if (sentinel.ai_next) { 578 /* 579 * If the returned entry is for an active connection, 580 * and the given name is not numeric, reorder the 581 * list, so that the application would try the list 582 * in the most efficient order. 583 */ 584 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 585 if (!numeric) 586 (void)reorder(&sentinel); 587 } 588 *res = sentinel.ai_next; 589 return SUCCESS; 590 } else 591 error = EAI_FAIL; 592 } 593free: 594bad: 595 if (sentinel.ai_next) 596 freeaddrinfo(sentinel.ai_next); 597 *res = NULL; 598 return error; 599} 600 601static int 602reorder(sentinel) 603 struct addrinfo *sentinel; 604{ 605 struct addrinfo *ai, **aip; 606 struct ai_order *aio; 607 int i, n; 608 struct policyhead policyhead; 609 610 /* count the number of addrinfo elements for sorting. */ 611 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 612 ; 613 614 /* 615 * If the number is small enough, we can skip the reordering process. 616 */ 617 if (n <= 1) 618 return(n); 619 620 /* allocate a temporary array for sort and initialization of it. */ 621 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 622 return(n); /* give up reordering */ 623 memset(aio, 0, sizeof(*aio) * n); 624 625 /* retrieve address selection policy from the kernel */ 626 TAILQ_INIT(&policyhead); 627 if (!get_addrselectpolicy(&policyhead)) { 628 /* no policy is installed into kernel, we don't sort. */ 629 free(aio); 630 return (n); 631 } 632 633 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 634 aio[i].aio_ai = ai; 635 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 636 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 637 &policyhead); 638 set_source(&aio[i], &policyhead); 639 } 640 641 /* perform sorting. */ 642 qsort(aio, n, sizeof(*aio), comp_dst); 643 644 /* reorder the addrinfo chain. */ 645 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 646 *aip = aio[i].aio_ai; 647 aip = &aio[i].aio_ai->ai_next; 648 } 649 *aip = NULL; 650 651 /* cleanup and return */ 652 free(aio); 653 free_addrselectpolicy(&policyhead); 654 return(n); 655} 656 657static int 658get_addrselectpolicy(head) 659 struct policyhead *head; 660{ 661#ifdef INET6 662 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 663 size_t l; 664 char *buf; 665 struct in6_addrpolicy *pol, *ep; 666 667 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 668 return (0); 669 if ((buf = malloc(l)) == NULL) 670 return (0); 671 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 672 free(buf); 673 return (0); 674 } 675 676 ep = (struct in6_addrpolicy *)(buf + l); 677 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 678 struct policyqueue *new; 679 680 if ((new = malloc(sizeof(*new))) == NULL) { 681 free_addrselectpolicy(head); /* make the list empty */ 682 break; 683 } 684 new->pc_policy = *pol; 685 TAILQ_INSERT_TAIL(head, new, pc_entry); 686 } 687 688 free(buf); 689 return (1); 690#else 691 return (0); 692#endif 693} 694 695static void 696free_addrselectpolicy(head) 697 struct policyhead *head; 698{ 699 struct policyqueue *ent, *nent; 700 701 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 702 nent = TAILQ_NEXT(ent, pc_entry); 703 TAILQ_REMOVE(head, ent, pc_entry); 704 free(ent); 705 } 706} 707 708static struct policyqueue * 709match_addrselectpolicy(addr, head) 710 struct sockaddr *addr; 711 struct policyhead *head; 712{ 713#ifdef INET6 714 struct policyqueue *ent, *bestent = NULL; 715 struct in6_addrpolicy *pol; 716 int matchlen, bestmatchlen = -1; 717 u_char *mp, *ep, *k, *p, m; 718 struct sockaddr_in6 key; 719 720 switch(addr->sa_family) { 721 case AF_INET6: 722 key = *(struct sockaddr_in6 *)addr; 723 break; 724 case AF_INET: 725 /* convert the address into IPv4-mapped IPv6 address. */ 726 memset(&key, 0, sizeof(key)); 727 key.sin6_family = AF_INET6; 728 key.sin6_len = sizeof(key); 729 key.sin6_addr.s6_addr[10] = 0xff; 730 key.sin6_addr.s6_addr[11] = 0xff; 731 memcpy(&key.sin6_addr.s6_addr[12], 732 &((struct sockaddr_in *)addr)->sin_addr, 4); 733 break; 734 default: 735 return(NULL); 736 } 737 738 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 739 pol = &ent->pc_policy; 740 matchlen = 0; 741 742 mp = (u_char *)&pol->addrmask.sin6_addr; 743 ep = mp + 16; /* XXX: scope field? */ 744 k = (u_char *)&key.sin6_addr; 745 p = (u_char *)&pol->addr.sin6_addr; 746 for (; mp < ep && *mp; mp++, k++, p++) { 747 m = *mp; 748 if ((*k & m) != *p) 749 goto next; /* not match */ 750 if (m == 0xff) /* short cut for a typical case */ 751 matchlen += 8; 752 else { 753 while (m >= 0x80) { 754 matchlen++; 755 m <<= 1; 756 } 757 } 758 } 759 760 /* matched. check if this is better than the current best. */ 761 if (matchlen > bestmatchlen) { 762 bestent = ent; 763 bestmatchlen = matchlen; 764 } 765 766 next: 767 continue; 768 } 769 770 return(bestent); 771#else 772 return(NULL); 773#endif 774 775} 776 777static void 778set_source(aio, ph) 779 struct ai_order *aio; 780 struct policyhead *ph; 781{ 782 struct addrinfo ai = *aio->aio_ai; 783 struct sockaddr_storage ss; 784 socklen_t srclen; 785 int s; 786 787 /* set unspec ("no source is available"), just in case */ 788 aio->aio_srcsa.sa_family = AF_UNSPEC; 789 aio->aio_srcscope = -1; 790 791 switch(ai.ai_family) { 792 case AF_INET: 793#ifdef INET6 794 case AF_INET6: 795#endif 796 break; 797 default: /* ignore unsupported AFs explicitly */ 798 return; 799 } 800 801 /* XXX: make a dummy addrinfo to call connect() */ 802 ai.ai_socktype = SOCK_DGRAM; 803 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 804 ai.ai_next = NULL; 805 memset(&ss, 0, sizeof(ss)); 806 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 807 ai.ai_addr = (struct sockaddr *)&ss; 808 get_port(&ai, "1", 0); 809 810 /* open a socket to get the source address for the given dst */ 811 if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0) 812 return; /* give up */ 813 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 814 goto cleanup; 815 srclen = ai.ai_addrlen; 816 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 817 aio->aio_srcsa.sa_family = AF_UNSPEC; 818 goto cleanup; 819 } 820 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 821 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 822 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 823#ifdef INET6 824 if (ai.ai_family == AF_INET6) { 825 struct in6_ifreq ifr6; 826 u_int32_t flags6; 827 828 /* XXX: interface name should not be hardcoded */ 829 strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name)); 830 memset(&ifr6, 0, sizeof(ifr6)); 831 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 832 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 833 flags6 = ifr6.ifr_ifru.ifru_flags6; 834 if ((flags6 & IN6_IFF_DEPRECATED)) 835 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 836 } 837 } 838#endif 839 840 cleanup: 841 _close(s); 842 return; 843} 844 845static int 846matchlen(src, dst) 847 struct sockaddr *src, *dst; 848{ 849 int match = 0; 850 u_char *s, *d; 851 u_char *lim, r; 852 int addrlen; 853 854 switch (src->sa_family) { 855#ifdef INET6 856 case AF_INET6: 857 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 858 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 859 addrlen = sizeof(struct in6_addr); 860 lim = s + addrlen; 861 break; 862#endif 863 case AF_INET: 864 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; 865 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; 866 addrlen = sizeof(struct in_addr); 867 lim = s + addrlen; 868 break; 869 default: 870 return(0); 871 } 872 873 while (s < lim) 874 if ((r = (*d++ ^ *s++)) != 0) { 875 while (r < addrlen * 8) { 876 match++; 877 r <<= 1; 878 } 879 break; 880 } else 881 match += 8; 882 return(match); 883} 884 885static int 886comp_dst(arg1, arg2) 887 const void *arg1, *arg2; 888{ 889 const struct ai_order *dst1 = arg1, *dst2 = arg2; 890 891 /* 892 * Rule 1: Avoid unusable destinations. 893 * XXX: we currently do not consider if an appropriate route exists. 894 */ 895 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 896 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 897 return(-1); 898 } 899 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 900 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 901 return(1); 902 } 903 904 /* Rule 2: Prefer matching scope. */ 905 if (dst1->aio_dstscope == dst1->aio_srcscope && 906 dst2->aio_dstscope != dst2->aio_srcscope) { 907 return(-1); 908 } 909 if (dst1->aio_dstscope != dst1->aio_srcscope && 910 dst2->aio_dstscope == dst2->aio_srcscope) { 911 return(1); 912 } 913 914 /* Rule 3: Avoid deprecated addresses. */ 915 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 916 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 917 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 918 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 919 return(-1); 920 } 921 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 922 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 923 return(1); 924 } 925 } 926 927 /* Rule 4: Prefer home addresses. */ 928 /* XXX: not implemented yet */ 929 930 /* Rule 5: Prefer matching label. */ 931#ifdef INET6 932 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 933 dst1->aio_srcpolicy->pc_policy.label == 934 dst1->aio_dstpolicy->pc_policy.label && 935 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 936 dst2->aio_srcpolicy->pc_policy.label != 937 dst2->aio_dstpolicy->pc_policy.label)) { 938 return(-1); 939 } 940 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 941 dst2->aio_srcpolicy->pc_policy.label == 942 dst2->aio_dstpolicy->pc_policy.label && 943 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 944 dst1->aio_srcpolicy->pc_policy.label != 945 dst1->aio_dstpolicy->pc_policy.label)) { 946 return(1); 947 } 948#endif 949 950 /* Rule 6: Prefer higher precedence. */ 951#ifdef INET6 952 if (dst1->aio_dstpolicy && 953 (dst2->aio_dstpolicy == NULL || 954 dst1->aio_dstpolicy->pc_policy.preced > 955 dst2->aio_dstpolicy->pc_policy.preced)) { 956 return(-1); 957 } 958 if (dst2->aio_dstpolicy && 959 (dst1->aio_dstpolicy == NULL || 960 dst2->aio_dstpolicy->pc_policy.preced > 961 dst1->aio_dstpolicy->pc_policy.preced)) { 962 return(1); 963 } 964#endif 965 966 /* Rule 7: Prefer native transport. */ 967 /* XXX: not implemented yet */ 968 969 /* Rule 8: Prefer smaller scope. */ 970 if (dst1->aio_dstscope >= 0 && 971 dst1->aio_dstscope < dst2->aio_dstscope) { 972 return(-1); 973 } 974 if (dst2->aio_dstscope >= 0 && 975 dst2->aio_dstscope < dst1->aio_dstscope) { 976 return(1); 977 } 978 979 /* 980 * Rule 9: Use longest matching prefix. 981 * We compare the match length in a same AF only. 982 */ 983 if (dst1->aio_ai->ai_addr->sa_family == 984 dst2->aio_ai->ai_addr->sa_family) { 985 if (dst1->aio_matchlen > dst2->aio_matchlen) { 986 return(-1); 987 } 988 if (dst1->aio_matchlen < dst2->aio_matchlen) { 989 return(1); 990 } 991 } 992 993 /* Rule 10: Otherwise, leave the order unchanged. */ 994 return(-1); 995} 996 997/* 998 * Copy from scope.c. 999 * XXX: we should standardize the functions and link them as standard 1000 * library. 1001 */ 1002static int 1003gai_addr2scopetype(sa) 1004 struct sockaddr *sa; 1005{ 1006#ifdef INET6 1007 struct sockaddr_in6 *sa6; 1008#endif 1009 struct sockaddr_in *sa4; 1010 1011 switch(sa->sa_family) { 1012#ifdef INET6 1013 case AF_INET6: 1014 sa6 = (struct sockaddr_in6 *)sa; 1015 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1016 /* just use the scope field of the multicast address */ 1017 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1018 } 1019 /* 1020 * Unicast addresses: map scope type to corresponding scope 1021 * value defined for multcast addresses. 1022 * XXX: hardcoded scope type values are bad... 1023 */ 1024 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1025 return(1); /* node local scope */ 1026 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1027 return(2); /* link-local scope */ 1028 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1029 return(5); /* site-local scope */ 1030 return(14); /* global scope */ 1031 break; 1032#endif 1033 case AF_INET: 1034 /* 1035 * IPv4 pseudo scoping according to RFC 3484. 1036 */ 1037 sa4 = (struct sockaddr_in *)sa; 1038 /* IPv4 autoconfiguration addresses have link-local scope. */ 1039 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1040 ((u_char *)&sa4->sin_addr)[1] == 254) 1041 return(2); 1042 /* Private addresses have site-local scope. */ 1043 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1044 (((u_char *)&sa4->sin_addr)[0] == 172 && 1045 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1046 (((u_char *)&sa4->sin_addr)[0] == 192 && 1047 ((u_char *)&sa4->sin_addr)[1] == 168)) 1048 return(14); /* XXX: It should be 5 unless NAT */ 1049 /* Loopback addresses have link-local scope. */ 1050 if (((u_char *)&sa4->sin_addr)[0] == 127) 1051 return(2); 1052 return(14); 1053 break; 1054 default: 1055 errno = EAFNOSUPPORT; /* is this a good error? */ 1056 return(-1); 1057 } 1058} 1059 1060/* 1061 * hostname == NULL. 1062 * passive socket -> anyaddr (0.0.0.0 or ::) 1063 * non-passive socket -> localhost (127.0.0.1 or ::1) 1064 */ 1065static int 1066explore_null(pai, servname, res) 1067 const struct addrinfo *pai; 1068 const char *servname; 1069 struct addrinfo **res; 1070{ 1071 int s; 1072 const struct afd *afd; 1073 struct addrinfo *cur; 1074 struct addrinfo sentinel; 1075 int error; 1076 1077 *res = NULL; 1078 sentinel.ai_next = NULL; 1079 cur = &sentinel; 1080 1081 /* 1082 * filter out AFs that are not supported by the kernel 1083 * XXX errno? 1084 */ 1085 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1086 if (s < 0) { 1087 if (errno != EMFILE) 1088 return 0; 1089 } else 1090 _close(s); 1091 1092 /* 1093 * if the servname does not match socktype/protocol, ignore it. 1094 */ 1095 if (get_portmatch(pai, servname) != 0) 1096 return 0; 1097 1098 afd = find_afd(pai->ai_family); 1099 if (afd == NULL) 1100 return 0; 1101 1102 if (pai->ai_flags & AI_PASSIVE) { 1103 GET_AI(cur->ai_next, afd, afd->a_addrany); 1104 /* xxx meaningless? 1105 * GET_CANONNAME(cur->ai_next, "anyaddr"); 1106 */ 1107 GET_PORT(cur->ai_next, servname); 1108 } else { 1109 GET_AI(cur->ai_next, afd, afd->a_loopback); 1110 /* xxx meaningless? 1111 * GET_CANONNAME(cur->ai_next, "localhost"); 1112 */ 1113 GET_PORT(cur->ai_next, servname); 1114 } 1115 cur = cur->ai_next; 1116 1117 *res = sentinel.ai_next; 1118 return 0; 1119 1120free: 1121 if (sentinel.ai_next) 1122 freeaddrinfo(sentinel.ai_next); 1123 return error; 1124} 1125 1126/* 1127 * numeric hostname 1128 */ 1129static int 1130explore_numeric(pai, hostname, servname, res, canonname) 1131 const struct addrinfo *pai; 1132 const char *hostname; 1133 const char *servname; 1134 struct addrinfo **res; 1135 const char *canonname; 1136{ 1137 const struct afd *afd; 1138 struct addrinfo *cur; 1139 struct addrinfo sentinel; 1140 int error; 1141 char pton[PTON_MAX]; 1142 1143 *res = NULL; 1144 sentinel.ai_next = NULL; 1145 cur = &sentinel; 1146 1147 /* 1148 * if the servname does not match socktype/protocol, ignore it. 1149 */ 1150 if (get_portmatch(pai, servname) != 0) 1151 return 0; 1152 1153 afd = find_afd(pai->ai_family); 1154 if (afd == NULL) 1155 return 0; 1156 1157 switch (afd->a_af) { 1158#if 1 /*X/Open spec*/ 1159 case AF_INET: 1160 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 1161 if (pai->ai_family == afd->a_af || 1162 pai->ai_family == PF_UNSPEC /*?*/) { 1163 GET_AI(cur->ai_next, afd, pton); 1164 GET_PORT(cur->ai_next, servname); 1165 if ((pai->ai_flags & AI_CANONNAME)) { 1166 /* 1167 * Set the numeric address itself as 1168 * the canonical name, based on a 1169 * clarification in rfc3493. 1170 */ 1171 GET_CANONNAME(cur->ai_next, canonname); 1172 } 1173 while (cur && cur->ai_next) 1174 cur = cur->ai_next; 1175 } else 1176 ERR(EAI_FAMILY); /*xxx*/ 1177 } 1178 break; 1179#endif 1180 default: 1181 if (inet_pton(afd->a_af, hostname, pton) == 1) { 1182 if (pai->ai_family == afd->a_af || 1183 pai->ai_family == PF_UNSPEC /*?*/) { 1184 GET_AI(cur->ai_next, afd, pton); 1185 GET_PORT(cur->ai_next, servname); 1186 if ((pai->ai_flags & AI_CANONNAME)) { 1187 /* 1188 * Set the numeric address itself as 1189 * the canonical name, based on a 1190 * clarification in rfc3493. 1191 */ 1192 GET_CANONNAME(cur->ai_next, canonname); 1193 } 1194 while (cur && cur->ai_next) 1195 cur = cur->ai_next; 1196 } else 1197 ERR(EAI_FAMILY); /* XXX */ 1198 } 1199 break; 1200 } 1201 1202 *res = sentinel.ai_next; 1203 return 0; 1204 1205free: 1206bad: 1207 if (sentinel.ai_next) 1208 freeaddrinfo(sentinel.ai_next); 1209 return error; 1210} 1211 1212/* 1213 * numeric hostname with scope 1214 */ 1215static int 1216explore_numeric_scope(pai, hostname, servname, res) 1217 const struct addrinfo *pai; 1218 const char *hostname; 1219 const char *servname; 1220 struct addrinfo **res; 1221{ 1222#if !defined(SCOPE_DELIMITER) || !defined(INET6) 1223 return explore_numeric(pai, hostname, servname, res, hostname); 1224#else 1225 const struct afd *afd; 1226 struct addrinfo *cur; 1227 int error; 1228 char *cp, *hostname2 = NULL, *scope, *addr; 1229 struct sockaddr_in6 *sin6; 1230 1231 /* 1232 * if the servname does not match socktype/protocol, ignore it. 1233 */ 1234 if (get_portmatch(pai, servname) != 0) 1235 return 0; 1236 1237 afd = find_afd(pai->ai_family); 1238 if (afd == NULL) 1239 return 0; 1240 1241 if (!afd->a_scoped) 1242 return explore_numeric(pai, hostname, servname, res, hostname); 1243 1244 cp = strchr(hostname, SCOPE_DELIMITER); 1245 if (cp == NULL) 1246 return explore_numeric(pai, hostname, servname, res, hostname); 1247 1248 /* 1249 * Handle special case of <scoped_address><delimiter><scope id> 1250 */ 1251 hostname2 = strdup(hostname); 1252 if (hostname2 == NULL) 1253 return EAI_MEMORY; 1254 /* terminate at the delimiter */ 1255 hostname2[cp - hostname] = '\0'; 1256 addr = hostname2; 1257 scope = cp + 1; 1258 1259 error = explore_numeric(pai, addr, servname, res, hostname); 1260 if (error == 0) { 1261 u_int32_t scopeid; 1262 1263 for (cur = *res; cur; cur = cur->ai_next) { 1264 if (cur->ai_family != AF_INET6) 1265 continue; 1266 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1267 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1268 free(hostname2); 1269 return(EAI_NONAME); /* XXX: is return OK? */ 1270 } 1271 sin6->sin6_scope_id = scopeid; 1272 } 1273 } 1274 1275 free(hostname2); 1276 1277 return error; 1278#endif 1279} 1280 1281static int 1282get_canonname(pai, ai, str) 1283 const struct addrinfo *pai; 1284 struct addrinfo *ai; 1285 const char *str; 1286{ 1287 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1288 ai->ai_canonname = strdup(str); 1289 if (ai->ai_canonname == NULL) 1290 return EAI_MEMORY; 1291 } 1292 return 0; 1293} 1294 1295static struct addrinfo * 1296get_ai(pai, afd, addr) 1297 const struct addrinfo *pai; 1298 const struct afd *afd; 1299 const char *addr; 1300{ 1301 char *p; 1302 struct addrinfo *ai; 1303#ifdef FAITH 1304 struct in6_addr faith_prefix; 1305 char *fp_str; 1306 int translate = 0; 1307#endif 1308 1309#ifdef FAITH 1310 /* 1311 * Transfrom an IPv4 addr into a special IPv6 addr format for 1312 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1313 * 1314 * +-----------------------------------+------------+ 1315 * | faith prefix part (12 bytes) | embedded | 1316 * | | IPv4 addr part (4 bytes) 1317 * +-----------------------------------+------------+ 1318 * 1319 * faith prefix part is specified as ascii IPv6 addr format 1320 * in environmental variable GAI. 1321 * For FAITH to work correctly, routing to faith prefix must be 1322 * setup toward a machine where a FAITH daemon operates. 1323 * Also, the machine must enable some mechanizm 1324 * (e.g. faith interface hack) to divert those packet with 1325 * faith prefixed destination addr to user-land FAITH daemon. 1326 */ 1327 fp_str = getenv("GAI"); 1328 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1329 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1330 u_int32_t v4a; 1331 u_int8_t v4a_top; 1332 1333 memcpy(&v4a, addr, sizeof v4a); 1334 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1335 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1336 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1337 afd = &afdl[N_INET6]; 1338 memcpy(&faith_prefix.s6_addr[12], addr, 1339 sizeof(struct in_addr)); 1340 translate = 1; 1341 } 1342 } 1343#endif 1344 1345 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1346 + (afd->a_socklen)); 1347 if (ai == NULL) 1348 return NULL; 1349 1350 memcpy(ai, pai, sizeof(struct addrinfo)); 1351 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1352 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1353 ai->ai_addr->sa_len = afd->a_socklen; 1354 ai->ai_addrlen = afd->a_socklen; 1355#if __LONG_BIT == 64 1356 ai->__ai_pad0 = 0; /* ABI compatibility */ 1357#endif 1358 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1359 p = (char *)(void *)(ai->ai_addr); 1360#ifdef FAITH 1361 if (translate == 1) 1362 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1363 else 1364#endif 1365 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1366 return ai; 1367} 1368 1369static int 1370get_portmatch(ai, servname) 1371 const struct addrinfo *ai; 1372 const char *servname; 1373{ 1374 1375 /* get_port does not touch first argument when matchonly == 1. */ 1376 /* LINTED const cast */ 1377 return get_port((struct addrinfo *)ai, servname, 1); 1378} 1379 1380static int 1381get_port(ai, servname, matchonly) 1382 struct addrinfo *ai; 1383 const char *servname; 1384 int matchonly; 1385{ 1386 const char *proto; 1387 struct servent *sp; 1388 int port; 1389 int allownumeric; 1390 1391 if (servname == NULL) 1392 return 0; 1393 switch (ai->ai_family) { 1394 case AF_INET: 1395#ifdef AF_INET6 1396 case AF_INET6: 1397#endif 1398 break; 1399 default: 1400 return 0; 1401 } 1402 1403 switch (ai->ai_socktype) { 1404 case SOCK_RAW: 1405 return EAI_SERVICE; 1406 case SOCK_DGRAM: 1407 case SOCK_STREAM: 1408 allownumeric = 1; 1409 break; 1410 case ANY: 1411 allownumeric = 0; 1412 break; 1413 default: 1414 return EAI_SOCKTYPE; 1415 } 1416 1417 port = str2number(servname); 1418 if (port >= 0) { 1419 if (!allownumeric) 1420 return EAI_SERVICE; 1421 if (port < 0 || port > 65535) 1422 return EAI_SERVICE; 1423 port = htons(port); 1424 } else { 1425 if (ai->ai_flags & AI_NUMERICSERV) 1426 return EAI_NONAME; 1427 switch (ai->ai_socktype) { 1428 case SOCK_DGRAM: 1429 proto = "udp"; 1430 break; 1431 case SOCK_STREAM: 1432 proto = "tcp"; 1433 break; 1434 default: 1435 proto = NULL; 1436 break; 1437 } 1438 1439 if ((sp = getservbyname(servname, proto)) == NULL) 1440 return EAI_SERVICE; 1441 port = sp->s_port; 1442 } 1443 1444 if (!matchonly) { 1445 switch (ai->ai_family) { 1446 case AF_INET: 1447 ((struct sockaddr_in *)(void *) 1448 ai->ai_addr)->sin_port = port; 1449 break; 1450#ifdef INET6 1451 case AF_INET6: 1452 ((struct sockaddr_in6 *)(void *) 1453 ai->ai_addr)->sin6_port = port; 1454 break; 1455#endif 1456 } 1457 } 1458 1459 return 0; 1460} 1461 1462static const struct afd * 1463find_afd(af) 1464 int af; 1465{ 1466 const struct afd *afd; 1467 1468 if (af == PF_UNSPEC) 1469 return NULL; 1470 for (afd = afdl; afd->a_af; afd++) { 1471 if (afd->a_af == af) 1472 return afd; 1473 } 1474 return NULL; 1475} 1476 1477/* 1478 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1479 * will take care of it. 1480 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1481 * if the code is right or not. 1482 * 1483 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1484 * _dns_getaddrinfo. 1485 */ 1486static int 1487addrconfig(pai) 1488 struct addrinfo *pai; 1489{ 1490 int s, af; 1491 1492 /* 1493 * TODO: 1494 * Note that implementation dependent test for address 1495 * configuration should be done everytime called 1496 * (or apropriate interval), 1497 * because addresses will be dynamically assigned or deleted. 1498 */ 1499 af = pai->ai_family; 1500 if (af == AF_UNSPEC) { 1501 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1502 af = AF_INET; 1503 else { 1504 _close(s); 1505 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1506 af = AF_INET6; 1507 else 1508 _close(s); 1509 } 1510 } 1511 if (af != AF_UNSPEC) { 1512 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1513 return 0; 1514 _close(s); 1515 } 1516 pai->ai_family = af; 1517 return 1; 1518} 1519 1520#ifdef INET6 1521/* convert a string to a scope identifier. XXX: IPv6 specific */ 1522static int 1523ip6_str2scopeid(scope, sin6, scopeid) 1524 char *scope; 1525 struct sockaddr_in6 *sin6; 1526 u_int32_t *scopeid; 1527{ 1528 u_long lscopeid; 1529 struct in6_addr *a6; 1530 char *ep; 1531 1532 a6 = &sin6->sin6_addr; 1533 1534 /* empty scopeid portion is invalid */ 1535 if (*scope == '\0') 1536 return -1; 1537 1538 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1539 /* 1540 * We currently assume a one-to-one mapping between links 1541 * and interfaces, so we simply use interface indices for 1542 * like-local scopes. 1543 */ 1544 *scopeid = if_nametoindex(scope); 1545 if (*scopeid == 0) 1546 goto trynumeric; 1547 return 0; 1548 } 1549 1550 /* still unclear about literal, allow numeric only - placeholder */ 1551 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1552 goto trynumeric; 1553 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1554 goto trynumeric; 1555 else 1556 goto trynumeric; /* global */ 1557 1558 /* try to convert to a numeric id as a last resort */ 1559 trynumeric: 1560 errno = 0; 1561 lscopeid = strtoul(scope, &ep, 10); 1562 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1563 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1564 return 0; 1565 else 1566 return -1; 1567} 1568#endif 1569 1570/* 1571 * FQDN hostname, DNS lookup 1572 */ 1573static int 1574explore_fqdn(pai, hostname, servname, res) 1575 const struct addrinfo *pai; 1576 const char *hostname; 1577 const char *servname; 1578 struct addrinfo **res; 1579{ 1580 struct addrinfo *result; 1581 struct addrinfo *cur; 1582 int error = 0; 1583 static const ns_dtab dtab[] = { 1584 NS_FILES_CB(_files_getaddrinfo, NULL) 1585 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1586 NS_NIS_CB(_yp_getaddrinfo, NULL) 1587 { 0 } 1588 }; 1589 1590 result = NULL; 1591 1592 /* 1593 * if the servname does not match socktype/protocol, ignore it. 1594 */ 1595 if (get_portmatch(pai, servname) != 0) 1596 return 0; 1597 1598 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1599 default_dns_files, hostname, pai)) { 1600 case NS_TRYAGAIN: 1601 error = EAI_AGAIN; 1602 goto free; 1603 case NS_UNAVAIL: 1604 error = EAI_FAIL; 1605 goto free; 1606 case NS_NOTFOUND: 1607 error = EAI_NONAME; 1608 goto free; 1609 case NS_SUCCESS: 1610 error = 0; 1611 for (cur = result; cur; cur = cur->ai_next) { 1612 GET_PORT(cur, servname); 1613 /* canonname should be filled already */ 1614 } 1615 break; 1616 } 1617 1618 *res = result; 1619 1620 return 0; 1621 1622free: 1623 if (result) 1624 freeaddrinfo(result); 1625 return error; 1626} 1627 1628#ifdef DEBUG 1629static const char AskedForGot[] = 1630 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1631#endif 1632 1633static struct addrinfo * 1634getanswer(answer, anslen, qname, qtype, pai) 1635 const querybuf *answer; 1636 int anslen; 1637 const char *qname; 1638 int qtype; 1639 const struct addrinfo *pai; 1640{ 1641 struct addrinfo sentinel, *cur; 1642 struct addrinfo ai; 1643 const struct afd *afd; 1644 char *canonname; 1645 const HEADER *hp; 1646 const u_char *cp; 1647 int n; 1648 const u_char *eom; 1649 char *bp, *ep; 1650 int type, class, ancount, qdcount; 1651 int haveanswer, had_error; 1652 char tbuf[MAXDNAME]; 1653 int (*name_ok)(const char *); 1654 char hostbuf[8*1024]; 1655 1656 memset(&sentinel, 0, sizeof(sentinel)); 1657 cur = &sentinel; 1658 1659 canonname = NULL; 1660 eom = answer->buf + anslen; 1661 switch (qtype) { 1662 case T_A: 1663 case T_AAAA: 1664 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1665 name_ok = res_hnok; 1666 break; 1667 default: 1668 return (NULL); /* XXX should be abort(); */ 1669 } 1670 /* 1671 * find first satisfactory answer 1672 */ 1673 hp = &answer->hdr; 1674 ancount = ntohs(hp->ancount); 1675 qdcount = ntohs(hp->qdcount); 1676 bp = hostbuf; 1677 ep = hostbuf + sizeof hostbuf; 1678 cp = answer->buf + HFIXEDSZ; 1679 if (qdcount != 1) { 1680 h_errno = NO_RECOVERY; 1681 return (NULL); 1682 } 1683 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1684 if ((n < 0) || !(*name_ok)(bp)) { 1685 h_errno = NO_RECOVERY; 1686 return (NULL); 1687 } 1688 cp += n + QFIXEDSZ; 1689 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1690 /* res_send() has already verified that the query name is the 1691 * same as the one we sent; this just gets the expanded name 1692 * (i.e., with the succeeding search-domain tacked on). 1693 */ 1694 n = strlen(bp) + 1; /* for the \0 */ 1695 if (n >= MAXHOSTNAMELEN) { 1696 h_errno = NO_RECOVERY; 1697 return (NULL); 1698 } 1699 canonname = bp; 1700 bp += n; 1701 /* The qname can be abbreviated, but h_name is now absolute. */ 1702 qname = canonname; 1703 } 1704 haveanswer = 0; 1705 had_error = 0; 1706 while (ancount-- > 0 && cp < eom && !had_error) { 1707 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1708 if ((n < 0) || !(*name_ok)(bp)) { 1709 had_error++; 1710 continue; 1711 } 1712 cp += n; /* name */ 1713 type = _getshort(cp); 1714 cp += INT16SZ; /* type */ 1715 class = _getshort(cp); 1716 cp += INT16SZ + INT32SZ; /* class, TTL */ 1717 n = _getshort(cp); 1718 cp += INT16SZ; /* len */ 1719 if (class != C_IN) { 1720 /* XXX - debug? syslog? */ 1721 cp += n; 1722 continue; /* XXX - had_error++ ? */ 1723 } 1724 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1725 type == T_CNAME) { 1726 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1727 if ((n < 0) || !(*name_ok)(tbuf)) { 1728 had_error++; 1729 continue; 1730 } 1731 cp += n; 1732 /* Get canonical name. */ 1733 n = strlen(tbuf) + 1; /* for the \0 */ 1734 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1735 had_error++; 1736 continue; 1737 } 1738 strlcpy(bp, tbuf, ep - bp); 1739 canonname = bp; 1740 bp += n; 1741 continue; 1742 } 1743 if (qtype == T_ANY) { 1744 if (!(type == T_A || type == T_AAAA)) { 1745 cp += n; 1746 continue; 1747 } 1748 } else if (type != qtype) { 1749#ifdef DEBUG 1750 if (type != T_KEY && type != T_SIG) 1751 syslog(LOG_NOTICE|LOG_AUTH, 1752 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1753 qname, p_class(C_IN), p_type(qtype), 1754 p_type(type)); 1755#endif 1756 cp += n; 1757 continue; /* XXX - had_error++ ? */ 1758 } 1759 switch (type) { 1760 case T_A: 1761 case T_AAAA: 1762 if (strcasecmp(canonname, bp) != 0) { 1763#ifdef DEBUG 1764 syslog(LOG_NOTICE|LOG_AUTH, 1765 AskedForGot, canonname, bp); 1766#endif 1767 cp += n; 1768 continue; /* XXX - had_error++ ? */ 1769 } 1770 if (type == T_A && n != INADDRSZ) { 1771 cp += n; 1772 continue; 1773 } 1774 if (type == T_AAAA && n != IN6ADDRSZ) { 1775 cp += n; 1776 continue; 1777 } 1778#ifdef FILTER_V4MAPPED 1779 if (type == T_AAAA) { 1780 struct in6_addr in6; 1781 memcpy(&in6, cp, sizeof(in6)); 1782 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1783 cp += n; 1784 continue; 1785 } 1786 } 1787#endif 1788 if (!haveanswer) { 1789 int nn; 1790 1791 canonname = bp; 1792 nn = strlen(bp) + 1; /* for the \0 */ 1793 bp += nn; 1794 } 1795 1796 /* don't overwrite pai */ 1797 ai = *pai; 1798 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1799 afd = find_afd(ai.ai_family); 1800 if (afd == NULL) { 1801 cp += n; 1802 continue; 1803 } 1804 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1805 if (cur->ai_next == NULL) 1806 had_error++; 1807 while (cur && cur->ai_next) 1808 cur = cur->ai_next; 1809 cp += n; 1810 break; 1811 default: 1812 abort(); 1813 } 1814 if (!had_error) 1815 haveanswer++; 1816 } 1817 if (haveanswer) { 1818#if defined(RESOLVSORT) 1819 /* 1820 * We support only IPv4 address for backward 1821 * compatibility against gethostbyname(3). 1822 */ 1823 if (_res.nsort && qtype == T_A) { 1824 if (addr4sort(&sentinel) < 0) { 1825 freeaddrinfo(sentinel.ai_next); 1826 h_errno = NO_RECOVERY; 1827 return NULL; 1828 } 1829 } 1830#endif /*RESOLVSORT*/ 1831 if (!canonname) 1832 (void)get_canonname(pai, sentinel.ai_next, qname); 1833 else 1834 (void)get_canonname(pai, sentinel.ai_next, canonname); 1835 h_errno = NETDB_SUCCESS; 1836 return sentinel.ai_next; 1837 } 1838 1839 h_errno = NO_RECOVERY; 1840 return NULL; 1841} 1842 1843#ifdef RESOLVSORT 1844struct addr_ptr { 1845 struct addrinfo *ai; 1846 int aval; 1847}; 1848 1849static int 1850addr4sort(struct addrinfo *sentinel) 1851{ 1852 struct addrinfo *ai; 1853 struct addr_ptr *addrs, addr; 1854 struct sockaddr_in *sin; 1855 int naddrs, i, j; 1856 int needsort = 0; 1857 1858 if (!sentinel) 1859 return -1; 1860 naddrs = 0; 1861 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1862 naddrs++; 1863 if (naddrs < 2) 1864 return 0; /* We don't need sorting. */ 1865 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1866 return -1; 1867 i = 0; 1868 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1869 sin = (struct sockaddr_in *)ai->ai_addr; 1870 for (j = 0; (unsigned)j < _res.nsort; j++) { 1871 if (_res.sort_list[j].addr.s_addr == 1872 (sin->sin_addr.s_addr & _res.sort_list[j].mask)) 1873 break; 1874 } 1875 addrs[i].ai = ai; 1876 addrs[i].aval = j; 1877 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1878 needsort = i; 1879 i++; 1880 } 1881 if (!needsort) { 1882 free(addrs); 1883 return 0; 1884 } 1885 1886 while (needsort < naddrs) { 1887 for (j = needsort - 1; j >= 0; j--) { 1888 if (addrs[j].aval > addrs[j+1].aval) { 1889 addr = addrs[j]; 1890 addrs[j] = addrs[j + 1]; 1891 addrs[j + 1] = addr; 1892 } else 1893 break; 1894 } 1895 needsort++; 1896 } 1897 1898 ai = sentinel; 1899 for (i = 0; i < naddrs; ++i) { 1900 ai->ai_next = addrs[i].ai; 1901 ai = ai->ai_next; 1902 } 1903 ai->ai_next = NULL; 1904 free(addrs); 1905 return 0; 1906} 1907#endif /*RESOLVSORT*/ 1908 1909/*ARGSUSED*/ 1910static int 1911_dns_getaddrinfo(rv, cb_data, ap) 1912 void *rv; 1913 void *cb_data; 1914 va_list ap; 1915{ 1916 struct addrinfo *ai; 1917 querybuf *buf, *buf2; 1918 const char *hostname; 1919 const struct addrinfo *pai; 1920 struct addrinfo sentinel, *cur; 1921 struct res_target q, q2; 1922 1923 hostname = va_arg(ap, char *); 1924 pai = va_arg(ap, const struct addrinfo *); 1925 1926 memset(&q, 0, sizeof(q2)); 1927 memset(&q2, 0, sizeof(q2)); 1928 memset(&sentinel, 0, sizeof(sentinel)); 1929 cur = &sentinel; 1930 1931 buf = malloc(sizeof(*buf)); 1932 if (!buf) { 1933 h_errno = NETDB_INTERNAL; 1934 return NS_NOTFOUND; 1935 } 1936 buf2 = malloc(sizeof(*buf2)); 1937 if (!buf2) { 1938 free(buf); 1939 h_errno = NETDB_INTERNAL; 1940 return NS_NOTFOUND; 1941 } 1942 1943 switch (pai->ai_family) { 1944 case AF_UNSPEC: 1945 q.name = hostname; 1946 q.qclass = C_IN; 1947 q.qtype = T_A; 1948 q.answer = buf->buf; 1949 q.anslen = sizeof(buf->buf); 1950 q.next = &q2; 1951 q2.name = hostname; 1952 q2.qclass = C_IN; 1953 q2.qtype = T_AAAA; 1954 q2.answer = buf2->buf; 1955 q2.anslen = sizeof(buf2->buf); 1956 break; 1957 case AF_INET: 1958 q.name = hostname; 1959 q.qclass = C_IN; 1960 q.qtype = T_A; 1961 q.answer = buf->buf; 1962 q.anslen = sizeof(buf->buf); 1963 break; 1964 case AF_INET6: 1965 q.name = hostname; 1966 q.qclass = C_IN; 1967 q.qtype = T_AAAA; 1968 q.answer = buf->buf; 1969 q.anslen = sizeof(buf->buf); 1970 break; 1971 default: 1972 free(buf); 1973 free(buf2); 1974 return NS_UNAVAIL; 1975 } 1976 if (res_searchN(hostname, &q) < 0) { 1977 free(buf); 1978 free(buf2); 1979 return NS_NOTFOUND; 1980 } 1981 /* prefer IPv6 */ 1982 if (q.next) { 1983 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai); 1984 if (ai) { 1985 cur->ai_next = ai; 1986 while (cur && cur->ai_next) 1987 cur = cur->ai_next; 1988 } 1989 } 1990 ai = getanswer(buf, q.n, q.name, q.qtype, pai); 1991 if (ai) 1992 cur->ai_next = ai; 1993 free(buf); 1994 free(buf2); 1995 if (sentinel.ai_next == NULL) 1996 switch (h_errno) { 1997 case HOST_NOT_FOUND: 1998 return NS_NOTFOUND; 1999 case TRY_AGAIN: 2000 return NS_TRYAGAIN; 2001 default: 2002 return NS_UNAVAIL; 2003 } 2004 *((struct addrinfo **)rv) = sentinel.ai_next; 2005 return NS_SUCCESS; 2006} 2007 2008static void 2009_sethtent(FILE **hostf) 2010{ 2011 if (!*hostf) 2012 *hostf = fopen(_PATH_HOSTS, "r"); 2013 else 2014 rewind(*hostf); 2015} 2016 2017static void 2018_endhtent(FILE **hostf) 2019{ 2020 if (*hostf) { 2021 (void) fclose(*hostf); 2022 *hostf = NULL; 2023 } 2024} 2025 2026static struct addrinfo * 2027_gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2028{ 2029 char *p; 2030 char *cp, *tname, *cname; 2031 struct addrinfo hints, *res0, *res; 2032 int error; 2033 const char *addr; 2034 char hostbuf[8*1024]; 2035 2036 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "r"))) 2037 return (NULL); 2038again: 2039 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 2040 return (NULL); 2041 if (*p == '#') 2042 goto again; 2043 cp = strpbrk(p, "#\n"); 2044 if (cp != NULL) 2045 *cp = '\0'; 2046 if (!(cp = strpbrk(p, " \t"))) 2047 goto again; 2048 *cp++ = '\0'; 2049 addr = p; 2050 cname = NULL; 2051 /* if this is not something we're looking for, skip it. */ 2052 while (cp && *cp) { 2053 if (*cp == ' ' || *cp == '\t') { 2054 cp++; 2055 continue; 2056 } 2057 tname = cp; 2058 if (cname == NULL) 2059 cname = cp; 2060 if ((cp = strpbrk(cp, " \t")) != NULL) 2061 *cp++ = '\0'; 2062 if (strcasecmp(name, tname) == 0) 2063 goto found; 2064 } 2065 goto again; 2066 2067found: 2068 /* we should not glob socktype/protocol here */ 2069 memset(&hints, 0, sizeof(hints)); 2070 hints.ai_family = pai->ai_family; 2071 hints.ai_socktype = SOCK_DGRAM; 2072 hints.ai_protocol = 0; 2073 hints.ai_flags = AI_NUMERICHOST; 2074 error = getaddrinfo(addr, "0", &hints, &res0); 2075 if (error) 2076 goto again; 2077#ifdef FILTER_V4MAPPED 2078 /* XXX should check all items in the chain */ 2079 if (res0->ai_family == AF_INET6 && 2080 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2081 freeaddrinfo(res0); 2082 goto again; 2083 } 2084#endif 2085 for (res = res0; res; res = res->ai_next) { 2086 /* cover it up */ 2087 res->ai_flags = pai->ai_flags; 2088 res->ai_socktype = pai->ai_socktype; 2089 res->ai_protocol = pai->ai_protocol; 2090 2091 if (pai->ai_flags & AI_CANONNAME) { 2092 if (get_canonname(pai, res, cname) != 0) { 2093 freeaddrinfo(res0); 2094 goto again; 2095 } 2096 } 2097 } 2098 return res0; 2099} 2100 2101/*ARGSUSED*/ 2102static int 2103_files_getaddrinfo(rv, cb_data, ap) 2104 void *rv; 2105 void *cb_data; 2106 va_list ap; 2107{ 2108 const char *name; 2109 const struct addrinfo *pai; 2110 struct addrinfo sentinel, *cur; 2111 struct addrinfo *p; 2112 FILE *hostf = NULL; 2113 2114 name = va_arg(ap, char *); 2115 pai = va_arg(ap, struct addrinfo *); 2116 2117 memset(&sentinel, 0, sizeof(sentinel)); 2118 cur = &sentinel; 2119 2120 _sethtent(&hostf); 2121 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2122 cur->ai_next = p; 2123 while (cur && cur->ai_next) 2124 cur = cur->ai_next; 2125 } 2126 _endhtent(&hostf); 2127 2128 *((struct addrinfo **)rv) = sentinel.ai_next; 2129 if (sentinel.ai_next == NULL) 2130 return NS_NOTFOUND; 2131 return NS_SUCCESS; 2132} 2133 2134#ifdef YP 2135/*ARGSUSED*/ 2136static struct addrinfo * 2137_yphostent(line, pai) 2138 char *line; 2139 const struct addrinfo *pai; 2140{ 2141 struct addrinfo sentinel, *cur; 2142 struct addrinfo hints, *res, *res0; 2143 int error; 2144 char *p = line; 2145 const char *addr, *canonname; 2146 char *nextline; 2147 char *cp; 2148 2149 addr = canonname = NULL; 2150 2151 memset(&sentinel, 0, sizeof(sentinel)); 2152 cur = &sentinel; 2153 2154nextline: 2155 /* terminate line */ 2156 cp = strchr(p, '\n'); 2157 if (cp) { 2158 *cp++ = '\0'; 2159 nextline = cp; 2160 } else 2161 nextline = NULL; 2162 2163 cp = strpbrk(p, " \t"); 2164 if (cp == NULL) { 2165 if (canonname == NULL) 2166 return (NULL); 2167 else 2168 goto done; 2169 } 2170 *cp++ = '\0'; 2171 2172 addr = p; 2173 2174 while (cp && *cp) { 2175 if (*cp == ' ' || *cp == '\t') { 2176 cp++; 2177 continue; 2178 } 2179 if (!canonname) 2180 canonname = cp; 2181 if ((cp = strpbrk(cp, " \t")) != NULL) 2182 *cp++ = '\0'; 2183 } 2184 2185 hints = *pai; 2186 hints.ai_flags = AI_NUMERICHOST; 2187 error = getaddrinfo(addr, NULL, &hints, &res0); 2188 if (error == 0) { 2189 for (res = res0; res; res = res->ai_next) { 2190 /* cover it up */ 2191 res->ai_flags = pai->ai_flags; 2192 2193 if (pai->ai_flags & AI_CANONNAME) 2194 (void)get_canonname(pai, res, canonname); 2195 } 2196 } else 2197 res0 = NULL; 2198 if (res0) { 2199 cur->ai_next = res0; 2200 while (cur && cur->ai_next) 2201 cur = cur->ai_next; 2202 } 2203 2204 if (nextline) { 2205 p = nextline; 2206 goto nextline; 2207 } 2208 2209done: 2210 return sentinel.ai_next; 2211} 2212 2213/*ARGSUSED*/ 2214static int 2215_yp_getaddrinfo(rv, cb_data, ap) 2216 void *rv; 2217 void *cb_data; 2218 va_list ap; 2219{ 2220 struct addrinfo sentinel, *cur; 2221 struct addrinfo *ai = NULL; 2222 char *ypbuf; 2223 int ypbuflen, r; 2224 const char *name; 2225 const struct addrinfo *pai; 2226 char *ypdomain; 2227 2228 if (_yp_check(&ypdomain) == 0) 2229 return NS_UNAVAIL; 2230 2231 name = va_arg(ap, char *); 2232 pai = va_arg(ap, const struct addrinfo *); 2233 2234 memset(&sentinel, 0, sizeof(sentinel)); 2235 cur = &sentinel; 2236 2237 /* hosts.byname is only for IPv4 (Solaris8) */ 2238 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2239 r = yp_match(ypdomain, "hosts.byname", name, 2240 (int)strlen(name), &ypbuf, &ypbuflen); 2241 if (r == 0) { 2242 struct addrinfo ai4; 2243 2244 ai4 = *pai; 2245 ai4.ai_family = AF_INET; 2246 ai = _yphostent(ypbuf, &ai4); 2247 if (ai) { 2248 cur->ai_next = ai; 2249 while (cur && cur->ai_next) 2250 cur = cur->ai_next; 2251 } 2252 free(ypbuf); 2253 } 2254 } 2255 2256 /* ipnodes.byname can hold both IPv4/v6 */ 2257 r = yp_match(ypdomain, "ipnodes.byname", name, 2258 (int)strlen(name), &ypbuf, &ypbuflen); 2259 if (r == 0) { 2260 ai = _yphostent(ypbuf, pai); 2261 if (ai) 2262 cur->ai_next = ai; 2263 free(ypbuf); 2264 } 2265 2266 if (sentinel.ai_next == NULL) { 2267 h_errno = HOST_NOT_FOUND; 2268 return NS_NOTFOUND; 2269 } 2270 *((struct addrinfo **)rv) = sentinel.ai_next; 2271 return NS_SUCCESS; 2272} 2273#endif 2274 2275/* resolver logic */ 2276 2277extern const char *_res_hostalias(const char *, char *, size_t); 2278 2279/* 2280 * Formulate a normal query, send, and await answer. 2281 * Returned answer is placed in supplied buffer "answer". 2282 * Perform preliminary check of answer, returning success only 2283 * if no error is indicated and the answer count is nonzero. 2284 * Return the size of the response on success, -1 on error. 2285 * Error number is left in h_errno. 2286 * 2287 * Caller must parse answer and determine whether it answers the question. 2288 */ 2289static int 2290res_queryN(name, target) 2291 const char *name; /* domain name */ 2292 struct res_target *target; 2293{ 2294 u_char *buf; 2295 HEADER *hp; 2296 int n; 2297 struct res_target *t; 2298 int rcode; 2299 int ancount; 2300 2301 rcode = NOERROR; 2302 ancount = 0; 2303 2304 buf = malloc(MAXPACKET); 2305 if (!buf) { 2306 h_errno = NETDB_INTERNAL; 2307 return -1; 2308 } 2309 2310 for (t = target; t; t = t->next) { 2311 int class, type; 2312 u_char *answer; 2313 int anslen; 2314 2315 hp = (HEADER *)(void *)t->answer; 2316 hp->rcode = NOERROR; /* default */ 2317 2318 /* make it easier... */ 2319 class = t->qclass; 2320 type = t->qtype; 2321 answer = t->answer; 2322 anslen = t->anslen; 2323#ifdef DEBUG 2324 if (_res.options & RES_DEBUG) 2325 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2326#endif 2327 2328 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, 2329 buf, MAXPACKET); 2330 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) 2331 n = res_opt(n, buf, MAXPACKET, anslen); 2332 if (n <= 0) { 2333#ifdef DEBUG 2334 if (_res.options & RES_DEBUG) 2335 printf(";; res_query: mkquery failed\n"); 2336#endif 2337 free(buf); 2338 h_errno = NO_RECOVERY; 2339 return (n); 2340 } 2341 n = res_send(buf, n, answer, anslen); 2342#if 0 2343 if (n < 0) { 2344#ifdef DEBUG 2345 if (_res.options & RES_DEBUG) 2346 printf(";; res_query: send error\n"); 2347#endif 2348 free(buf); 2349 h_errno = TRY_AGAIN; 2350 return (n); 2351 } 2352#endif 2353 2354 if (n < 0 || n > anslen) 2355 hp->rcode = FORMERR; /* XXX not very informative */ 2356 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2357 rcode = hp->rcode; /* record most recent error */ 2358#ifdef DEBUG 2359 if (_res.options & RES_DEBUG) 2360 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2361 ntohs(hp->ancount)); 2362#endif 2363 continue; 2364 } 2365 2366 ancount += ntohs(hp->ancount); 2367 2368 t->n = n; 2369 } 2370 2371 free(buf); 2372 2373 if (ancount == 0) { 2374 switch (rcode) { 2375 case NXDOMAIN: 2376 h_errno = HOST_NOT_FOUND; 2377 break; 2378 case SERVFAIL: 2379 h_errno = TRY_AGAIN; 2380 break; 2381 case NOERROR: 2382 h_errno = NO_DATA; 2383 break; 2384 case FORMERR: 2385 case NOTIMP: 2386 case REFUSED: 2387 default: 2388 h_errno = NO_RECOVERY; 2389 break; 2390 } 2391 return (-1); 2392 } 2393 return (ancount); 2394} 2395 2396/* 2397 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2398 * Return the size of the response on success, -1 on error. 2399 * If enabled, implement search rules until answer or unrecoverable failure 2400 * is detected. Error code, if any, is left in h_errno. 2401 */ 2402static int 2403res_searchN(name, target) 2404 const char *name; /* domain name */ 2405 struct res_target *target; 2406{ 2407 const char *cp, * const *domain; 2408 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2409 u_int dots; 2410 int trailing_dot, ret, saved_herrno; 2411 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 2412 char abuf[MAXDNAME]; 2413 2414 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2415 h_errno = NETDB_INTERNAL; 2416 return (-1); 2417 } 2418 2419 errno = 0; 2420 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 2421 dots = 0; 2422 for (cp = name; *cp; cp++) 2423 dots += (*cp == '.'); 2424 trailing_dot = 0; 2425 if (cp > name && *--cp == '.') 2426 trailing_dot++; 2427 2428 /* 2429 * if there aren't any dots, it could be a user-level alias 2430 */ 2431 if (!dots && (cp = _res_hostalias(name, abuf, sizeof(abuf))) != NULL) 2432 return (res_queryN(cp, target)); 2433 2434 /* 2435 * If there are dots in the name already, let's just give it a try 2436 * 'as is'. The threshold can be set with the "ndots" option. 2437 */ 2438 saved_herrno = -1; 2439 if (dots >= _res.ndots) { 2440 ret = res_querydomainN(name, NULL, target); 2441 if (ret > 0) 2442 return (ret); 2443 saved_herrno = h_errno; 2444 tried_as_is++; 2445 } 2446 2447 /* 2448 * We do at least one level of search if 2449 * - there is no dot and RES_DEFNAME is set, or 2450 * - there is at least one dot, there is no trailing dot, 2451 * and RES_DNSRCH is set. 2452 */ 2453 if ((!dots && (_res.options & RES_DEFNAMES)) || 2454 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { 2455 int done = 0; 2456 2457 for (domain = (const char * const *)_res.dnsrch; 2458 *domain && !done; 2459 domain++) { 2460 2461 ret = res_querydomainN(name, *domain, target); 2462 if (ret > 0) 2463 return (ret); 2464 2465 /* 2466 * If no server present, give up. 2467 * If name isn't found in this domain, 2468 * keep trying higher domains in the search list 2469 * (if that's enabled). 2470 * On a NO_DATA error, keep trying, otherwise 2471 * a wildcard entry of another type could keep us 2472 * from finding this entry higher in the domain. 2473 * If we get some other error (negative answer or 2474 * server failure), then stop searching up, 2475 * but try the input name below in case it's 2476 * fully-qualified. 2477 */ 2478 if (errno == ECONNREFUSED) { 2479 h_errno = TRY_AGAIN; 2480 return (-1); 2481 } 2482 2483 switch (h_errno) { 2484 case NO_DATA: 2485 got_nodata++; 2486 /* FALLTHROUGH */ 2487 case HOST_NOT_FOUND: 2488 /* keep trying */ 2489 break; 2490 case TRY_AGAIN: 2491 if (hp->rcode == SERVFAIL) { 2492 /* try next search element, if any */ 2493 got_servfail++; 2494 break; 2495 } 2496 /* FALLTHROUGH */ 2497 default: 2498 /* anything else implies that we're done */ 2499 done++; 2500 } 2501 /* 2502 * if we got here for some reason other than DNSRCH, 2503 * we only wanted one iteration of the loop, so stop. 2504 */ 2505 if (!(_res.options & RES_DNSRCH)) 2506 done++; 2507 } 2508 } 2509 2510 /* 2511 * if we have not already tried the name "as is", do that now. 2512 * note that we do this regardless of how many dots were in the 2513 * name or whether it ends with a dot. 2514 */ 2515 if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) { 2516 ret = res_querydomainN(name, NULL, target); 2517 if (ret > 0) 2518 return (ret); 2519 } 2520 2521 /* 2522 * if we got here, we didn't satisfy the search. 2523 * if we did an initial full query, return that query's h_errno 2524 * (note that we wouldn't be here if that query had succeeded). 2525 * else if we ever got a nodata, send that back as the reason. 2526 * else send back meaningless h_errno, that being the one from 2527 * the last DNSRCH we did. 2528 */ 2529 if (saved_herrno != -1) 2530 h_errno = saved_herrno; 2531 else if (got_nodata) 2532 h_errno = NO_DATA; 2533 else if (got_servfail) 2534 h_errno = TRY_AGAIN; 2535 return (-1); 2536} 2537 2538/* 2539 * Perform a call on res_query on the concatenation of name and domain, 2540 * removing a trailing dot from name if domain is NULL. 2541 */ 2542static int 2543res_querydomainN(name, domain, target) 2544 const char *name, *domain; 2545 struct res_target *target; 2546{ 2547 char nbuf[MAXDNAME]; 2548 const char *longname = nbuf; 2549 size_t n, d; 2550 2551#ifdef DEBUG 2552 if (_res.options & RES_DEBUG) 2553 printf(";; res_querydomain(%s, %s)\n", 2554 name, domain?domain:"<Nil>"); 2555#endif 2556 if (domain == NULL) { 2557 /* 2558 * Check for trailing '.'; 2559 * copy without '.' if present. 2560 */ 2561 n = strlen(name); 2562 if (n >= MAXDNAME) { 2563 h_errno = NO_RECOVERY; 2564 return (-1); 2565 } 2566 if (n > 0 && name[--n] == '.') { 2567 strncpy(nbuf, name, n); 2568 nbuf[n] = '\0'; 2569 } else 2570 longname = name; 2571 } else { 2572 n = strlen(name); 2573 d = strlen(domain); 2574 if (n + d + 1 >= MAXDNAME) { 2575 h_errno = NO_RECOVERY; 2576 return (-1); 2577 } 2578 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2579 } 2580 return (res_queryN(longname, target)); 2581} 2582