getaddrinfo.c revision 156946
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 156946 2006-03-21 12:39:29Z delphij $"); 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 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1356 p = (char *)(void *)(ai->ai_addr); 1357#ifdef FAITH 1358 if (translate == 1) 1359 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1360 else 1361#endif 1362 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1363 return ai; 1364} 1365 1366static int 1367get_portmatch(ai, servname) 1368 const struct addrinfo *ai; 1369 const char *servname; 1370{ 1371 1372 /* get_port does not touch first argument when matchonly == 1. */ 1373 /* LINTED const cast */ 1374 return get_port((struct addrinfo *)ai, servname, 1); 1375} 1376 1377static int 1378get_port(ai, servname, matchonly) 1379 struct addrinfo *ai; 1380 const char *servname; 1381 int matchonly; 1382{ 1383 const char *proto; 1384 struct servent *sp; 1385 int port; 1386 int allownumeric; 1387 1388 if (servname == NULL) 1389 return 0; 1390 switch (ai->ai_family) { 1391 case AF_INET: 1392#ifdef AF_INET6 1393 case AF_INET6: 1394#endif 1395 break; 1396 default: 1397 return 0; 1398 } 1399 1400 switch (ai->ai_socktype) { 1401 case SOCK_RAW: 1402 return EAI_SERVICE; 1403 case SOCK_DGRAM: 1404 case SOCK_STREAM: 1405 allownumeric = 1; 1406 break; 1407 case ANY: 1408 allownumeric = 0; 1409 break; 1410 default: 1411 return EAI_SOCKTYPE; 1412 } 1413 1414 port = str2number(servname); 1415 if (port >= 0) { 1416 if (!allownumeric) 1417 return EAI_SERVICE; 1418 if (port < 0 || port > 65535) 1419 return EAI_SERVICE; 1420 port = htons(port); 1421 } else { 1422 if (ai->ai_flags & AI_NUMERICSERV) 1423 return EAI_NONAME; 1424 switch (ai->ai_socktype) { 1425 case SOCK_DGRAM: 1426 proto = "udp"; 1427 break; 1428 case SOCK_STREAM: 1429 proto = "tcp"; 1430 break; 1431 default: 1432 proto = NULL; 1433 break; 1434 } 1435 1436 if ((sp = getservbyname(servname, proto)) == NULL) 1437 return EAI_SERVICE; 1438 port = sp->s_port; 1439 } 1440 1441 if (!matchonly) { 1442 switch (ai->ai_family) { 1443 case AF_INET: 1444 ((struct sockaddr_in *)(void *) 1445 ai->ai_addr)->sin_port = port; 1446 break; 1447#ifdef INET6 1448 case AF_INET6: 1449 ((struct sockaddr_in6 *)(void *) 1450 ai->ai_addr)->sin6_port = port; 1451 break; 1452#endif 1453 } 1454 } 1455 1456 return 0; 1457} 1458 1459static const struct afd * 1460find_afd(af) 1461 int af; 1462{ 1463 const struct afd *afd; 1464 1465 if (af == PF_UNSPEC) 1466 return NULL; 1467 for (afd = afdl; afd->a_af; afd++) { 1468 if (afd->a_af == af) 1469 return afd; 1470 } 1471 return NULL; 1472} 1473 1474/* 1475 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1476 * will take care of it. 1477 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1478 * if the code is right or not. 1479 * 1480 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1481 * _dns_getaddrinfo. 1482 */ 1483static int 1484addrconfig(pai) 1485 struct addrinfo *pai; 1486{ 1487 int s, af; 1488 1489 /* 1490 * TODO: 1491 * Note that implementation dependent test for address 1492 * configuration should be done everytime called 1493 * (or apropriate interval), 1494 * because addresses will be dynamically assigned or deleted. 1495 */ 1496 af = pai->ai_family; 1497 if (af == AF_UNSPEC) { 1498 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1499 af = AF_INET; 1500 else { 1501 _close(s); 1502 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1503 af = AF_INET6; 1504 else 1505 _close(s); 1506 } 1507 } 1508 if (af != AF_UNSPEC) { 1509 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1510 return 0; 1511 _close(s); 1512 } 1513 pai->ai_family = af; 1514 return 1; 1515} 1516 1517#ifdef INET6 1518/* convert a string to a scope identifier. XXX: IPv6 specific */ 1519static int 1520ip6_str2scopeid(scope, sin6, scopeid) 1521 char *scope; 1522 struct sockaddr_in6 *sin6; 1523 u_int32_t *scopeid; 1524{ 1525 u_long lscopeid; 1526 struct in6_addr *a6; 1527 char *ep; 1528 1529 a6 = &sin6->sin6_addr; 1530 1531 /* empty scopeid portion is invalid */ 1532 if (*scope == '\0') 1533 return -1; 1534 1535 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1536 /* 1537 * We currently assume a one-to-one mapping between links 1538 * and interfaces, so we simply use interface indices for 1539 * like-local scopes. 1540 */ 1541 *scopeid = if_nametoindex(scope); 1542 if (*scopeid == 0) 1543 goto trynumeric; 1544 return 0; 1545 } 1546 1547 /* still unclear about literal, allow numeric only - placeholder */ 1548 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1549 goto trynumeric; 1550 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1551 goto trynumeric; 1552 else 1553 goto trynumeric; /* global */ 1554 1555 /* try to convert to a numeric id as a last resort */ 1556 trynumeric: 1557 errno = 0; 1558 lscopeid = strtoul(scope, &ep, 10); 1559 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1560 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1561 return 0; 1562 else 1563 return -1; 1564} 1565#endif 1566 1567/* 1568 * FQDN hostname, DNS lookup 1569 */ 1570static int 1571explore_fqdn(pai, hostname, servname, res) 1572 const struct addrinfo *pai; 1573 const char *hostname; 1574 const char *servname; 1575 struct addrinfo **res; 1576{ 1577 struct addrinfo *result; 1578 struct addrinfo *cur; 1579 int error = 0; 1580 static const ns_dtab dtab[] = { 1581 NS_FILES_CB(_files_getaddrinfo, NULL) 1582 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1583 NS_NIS_CB(_yp_getaddrinfo, NULL) 1584 { 0 } 1585 }; 1586 1587 result = NULL; 1588 1589 /* 1590 * if the servname does not match socktype/protocol, ignore it. 1591 */ 1592 if (get_portmatch(pai, servname) != 0) 1593 return 0; 1594 1595 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1596 default_dns_files, hostname, pai)) { 1597 case NS_TRYAGAIN: 1598 error = EAI_AGAIN; 1599 goto free; 1600 case NS_UNAVAIL: 1601 error = EAI_FAIL; 1602 goto free; 1603 case NS_NOTFOUND: 1604 error = EAI_NONAME; 1605 goto free; 1606 case NS_SUCCESS: 1607 error = 0; 1608 for (cur = result; cur; cur = cur->ai_next) { 1609 GET_PORT(cur, servname); 1610 /* canonname should be filled already */ 1611 } 1612 break; 1613 } 1614 1615 *res = result; 1616 1617 return 0; 1618 1619free: 1620 if (result) 1621 freeaddrinfo(result); 1622 return error; 1623} 1624 1625#ifdef DEBUG 1626static const char AskedForGot[] = 1627 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1628#endif 1629 1630static struct addrinfo * 1631getanswer(answer, anslen, qname, qtype, pai) 1632 const querybuf *answer; 1633 int anslen; 1634 const char *qname; 1635 int qtype; 1636 const struct addrinfo *pai; 1637{ 1638 struct addrinfo sentinel, *cur; 1639 struct addrinfo ai; 1640 const struct afd *afd; 1641 char *canonname; 1642 const HEADER *hp; 1643 const u_char *cp; 1644 int n; 1645 const u_char *eom; 1646 char *bp, *ep; 1647 int type, class, ancount, qdcount; 1648 int haveanswer, had_error; 1649 char tbuf[MAXDNAME]; 1650 int (*name_ok)(const char *); 1651 char hostbuf[8*1024]; 1652 1653 memset(&sentinel, 0, sizeof(sentinel)); 1654 cur = &sentinel; 1655 1656 canonname = NULL; 1657 eom = answer->buf + anslen; 1658 switch (qtype) { 1659 case T_A: 1660 case T_AAAA: 1661 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1662 name_ok = res_hnok; 1663 break; 1664 default: 1665 return (NULL); /* XXX should be abort(); */ 1666 } 1667 /* 1668 * find first satisfactory answer 1669 */ 1670 hp = &answer->hdr; 1671 ancount = ntohs(hp->ancount); 1672 qdcount = ntohs(hp->qdcount); 1673 bp = hostbuf; 1674 ep = hostbuf + sizeof hostbuf; 1675 cp = answer->buf + HFIXEDSZ; 1676 if (qdcount != 1) { 1677 h_errno = NO_RECOVERY; 1678 return (NULL); 1679 } 1680 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1681 if ((n < 0) || !(*name_ok)(bp)) { 1682 h_errno = NO_RECOVERY; 1683 return (NULL); 1684 } 1685 cp += n + QFIXEDSZ; 1686 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1687 /* res_send() has already verified that the query name is the 1688 * same as the one we sent; this just gets the expanded name 1689 * (i.e., with the succeeding search-domain tacked on). 1690 */ 1691 n = strlen(bp) + 1; /* for the \0 */ 1692 if (n >= MAXHOSTNAMELEN) { 1693 h_errno = NO_RECOVERY; 1694 return (NULL); 1695 } 1696 canonname = bp; 1697 bp += n; 1698 /* The qname can be abbreviated, but h_name is now absolute. */ 1699 qname = canonname; 1700 } 1701 haveanswer = 0; 1702 had_error = 0; 1703 while (ancount-- > 0 && cp < eom && !had_error) { 1704 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1705 if ((n < 0) || !(*name_ok)(bp)) { 1706 had_error++; 1707 continue; 1708 } 1709 cp += n; /* name */ 1710 type = _getshort(cp); 1711 cp += INT16SZ; /* type */ 1712 class = _getshort(cp); 1713 cp += INT16SZ + INT32SZ; /* class, TTL */ 1714 n = _getshort(cp); 1715 cp += INT16SZ; /* len */ 1716 if (class != C_IN) { 1717 /* XXX - debug? syslog? */ 1718 cp += n; 1719 continue; /* XXX - had_error++ ? */ 1720 } 1721 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1722 type == T_CNAME) { 1723 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1724 if ((n < 0) || !(*name_ok)(tbuf)) { 1725 had_error++; 1726 continue; 1727 } 1728 cp += n; 1729 /* Get canonical name. */ 1730 n = strlen(tbuf) + 1; /* for the \0 */ 1731 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1732 had_error++; 1733 continue; 1734 } 1735 strlcpy(bp, tbuf, ep - bp); 1736 canonname = bp; 1737 bp += n; 1738 continue; 1739 } 1740 if (qtype == T_ANY) { 1741 if (!(type == T_A || type == T_AAAA)) { 1742 cp += n; 1743 continue; 1744 } 1745 } else if (type != qtype) { 1746#ifdef DEBUG 1747 if (type != T_KEY && type != T_SIG) 1748 syslog(LOG_NOTICE|LOG_AUTH, 1749 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1750 qname, p_class(C_IN), p_type(qtype), 1751 p_type(type)); 1752#endif 1753 cp += n; 1754 continue; /* XXX - had_error++ ? */ 1755 } 1756 switch (type) { 1757 case T_A: 1758 case T_AAAA: 1759 if (strcasecmp(canonname, bp) != 0) { 1760#ifdef DEBUG 1761 syslog(LOG_NOTICE|LOG_AUTH, 1762 AskedForGot, canonname, bp); 1763#endif 1764 cp += n; 1765 continue; /* XXX - had_error++ ? */ 1766 } 1767 if (type == T_A && n != INADDRSZ) { 1768 cp += n; 1769 continue; 1770 } 1771 if (type == T_AAAA && n != IN6ADDRSZ) { 1772 cp += n; 1773 continue; 1774 } 1775#ifdef FILTER_V4MAPPED 1776 if (type == T_AAAA) { 1777 struct in6_addr in6; 1778 memcpy(&in6, cp, sizeof(in6)); 1779 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1780 cp += n; 1781 continue; 1782 } 1783 } 1784#endif 1785 if (!haveanswer) { 1786 int nn; 1787 1788 canonname = bp; 1789 nn = strlen(bp) + 1; /* for the \0 */ 1790 bp += nn; 1791 } 1792 1793 /* don't overwrite pai */ 1794 ai = *pai; 1795 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1796 afd = find_afd(ai.ai_family); 1797 if (afd == NULL) { 1798 cp += n; 1799 continue; 1800 } 1801 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1802 if (cur->ai_next == NULL) 1803 had_error++; 1804 while (cur && cur->ai_next) 1805 cur = cur->ai_next; 1806 cp += n; 1807 break; 1808 default: 1809 abort(); 1810 } 1811 if (!had_error) 1812 haveanswer++; 1813 } 1814 if (haveanswer) { 1815#if defined(RESOLVSORT) 1816 /* 1817 * We support only IPv4 address for backward 1818 * compatibility against gethostbyname(3). 1819 */ 1820 if (_res.nsort && qtype == T_A) { 1821 if (addr4sort(&sentinel) < 0) { 1822 freeaddrinfo(sentinel.ai_next); 1823 h_errno = NO_RECOVERY; 1824 return NULL; 1825 } 1826 } 1827#endif /*RESOLVSORT*/ 1828 if (!canonname) 1829 (void)get_canonname(pai, sentinel.ai_next, qname); 1830 else 1831 (void)get_canonname(pai, sentinel.ai_next, canonname); 1832 h_errno = NETDB_SUCCESS; 1833 return sentinel.ai_next; 1834 } 1835 1836 h_errno = NO_RECOVERY; 1837 return NULL; 1838} 1839 1840#ifdef RESOLVSORT 1841struct addr_ptr { 1842 struct addrinfo *ai; 1843 int aval; 1844}; 1845 1846static int 1847addr4sort(struct addrinfo *sentinel) 1848{ 1849 struct addrinfo *ai; 1850 struct addr_ptr *addrs, addr; 1851 struct sockaddr_in *sin; 1852 int naddrs, i, j; 1853 int needsort = 0; 1854 1855 if (!sentinel) 1856 return -1; 1857 naddrs = 0; 1858 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1859 naddrs++; 1860 if (naddrs < 2) 1861 return 0; /* We don't need sorting. */ 1862 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1863 return -1; 1864 i = 0; 1865 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1866 sin = (struct sockaddr_in *)ai->ai_addr; 1867 for (j = 0; (unsigned)j < _res.nsort; j++) { 1868 if (_res.sort_list[j].addr.s_addr == 1869 (sin->sin_addr.s_addr & _res.sort_list[j].mask)) 1870 break; 1871 } 1872 addrs[i].ai = ai; 1873 addrs[i].aval = j; 1874 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1875 needsort = i; 1876 i++; 1877 } 1878 if (!needsort) { 1879 free(addrs); 1880 return 0; 1881 } 1882 1883 while (needsort < naddrs) { 1884 for (j = needsort - 1; j >= 0; j--) { 1885 if (addrs[j].aval > addrs[j+1].aval) { 1886 addr = addrs[j]; 1887 addrs[j] = addrs[j + 1]; 1888 addrs[j + 1] = addr; 1889 } else 1890 break; 1891 } 1892 needsort++; 1893 } 1894 1895 ai = sentinel; 1896 for (i = 0; i < naddrs; ++i) { 1897 ai->ai_next = addrs[i].ai; 1898 ai = ai->ai_next; 1899 } 1900 ai->ai_next = NULL; 1901 free(addrs); 1902 return 0; 1903} 1904#endif /*RESOLVSORT*/ 1905 1906/*ARGSUSED*/ 1907static int 1908_dns_getaddrinfo(rv, cb_data, ap) 1909 void *rv; 1910 void *cb_data; 1911 va_list ap; 1912{ 1913 struct addrinfo *ai; 1914 querybuf *buf, *buf2; 1915 const char *hostname; 1916 const struct addrinfo *pai; 1917 struct addrinfo sentinel, *cur; 1918 struct res_target q, q2; 1919 1920 hostname = va_arg(ap, char *); 1921 pai = va_arg(ap, const struct addrinfo *); 1922 1923 memset(&q, 0, sizeof(q)); 1924 memset(&q2, 0, sizeof(q2)); 1925 memset(&sentinel, 0, sizeof(sentinel)); 1926 cur = &sentinel; 1927 1928 buf = malloc(sizeof(*buf)); 1929 if (!buf) { 1930 h_errno = NETDB_INTERNAL; 1931 return NS_NOTFOUND; 1932 } 1933 buf2 = malloc(sizeof(*buf2)); 1934 if (!buf2) { 1935 free(buf); 1936 h_errno = NETDB_INTERNAL; 1937 return NS_NOTFOUND; 1938 } 1939 1940 switch (pai->ai_family) { 1941 case AF_UNSPEC: 1942 q.name = hostname; 1943 q.qclass = C_IN; 1944 q.qtype = T_A; 1945 q.answer = buf->buf; 1946 q.anslen = sizeof(buf->buf); 1947 q.next = &q2; 1948 q2.name = hostname; 1949 q2.qclass = C_IN; 1950 q2.qtype = T_AAAA; 1951 q2.answer = buf2->buf; 1952 q2.anslen = sizeof(buf2->buf); 1953 break; 1954 case AF_INET: 1955 q.name = hostname; 1956 q.qclass = C_IN; 1957 q.qtype = T_A; 1958 q.answer = buf->buf; 1959 q.anslen = sizeof(buf->buf); 1960 break; 1961 case AF_INET6: 1962 q.name = hostname; 1963 q.qclass = C_IN; 1964 q.qtype = T_AAAA; 1965 q.answer = buf->buf; 1966 q.anslen = sizeof(buf->buf); 1967 break; 1968 default: 1969 free(buf); 1970 free(buf2); 1971 return NS_UNAVAIL; 1972 } 1973 if (res_searchN(hostname, &q) < 0) { 1974 free(buf); 1975 free(buf2); 1976 return NS_NOTFOUND; 1977 } 1978 /* prefer IPv6 */ 1979 if (q.next) { 1980 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai); 1981 if (ai) { 1982 cur->ai_next = ai; 1983 while (cur && cur->ai_next) 1984 cur = cur->ai_next; 1985 } 1986 } 1987 ai = getanswer(buf, q.n, q.name, q.qtype, pai); 1988 if (ai) 1989 cur->ai_next = ai; 1990 free(buf); 1991 free(buf2); 1992 if (sentinel.ai_next == NULL) 1993 switch (h_errno) { 1994 case HOST_NOT_FOUND: 1995 return NS_NOTFOUND; 1996 case TRY_AGAIN: 1997 return NS_TRYAGAIN; 1998 default: 1999 return NS_UNAVAIL; 2000 } 2001 *((struct addrinfo **)rv) = sentinel.ai_next; 2002 return NS_SUCCESS; 2003} 2004 2005static void 2006_sethtent(FILE **hostf) 2007{ 2008 if (!*hostf) 2009 *hostf = fopen(_PATH_HOSTS, "r"); 2010 else 2011 rewind(*hostf); 2012} 2013 2014static void 2015_endhtent(FILE **hostf) 2016{ 2017 if (*hostf) { 2018 (void) fclose(*hostf); 2019 *hostf = NULL; 2020 } 2021} 2022 2023static struct addrinfo * 2024_gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2025{ 2026 char *p; 2027 char *cp, *tname, *cname; 2028 struct addrinfo hints, *res0, *res; 2029 int error; 2030 const char *addr; 2031 char hostbuf[8*1024]; 2032 2033 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "r"))) 2034 return (NULL); 2035again: 2036 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 2037 return (NULL); 2038 if (*p == '#') 2039 goto again; 2040 cp = strpbrk(p, "#\n"); 2041 if (cp != NULL) 2042 *cp = '\0'; 2043 if (!(cp = strpbrk(p, " \t"))) 2044 goto again; 2045 *cp++ = '\0'; 2046 addr = p; 2047 cname = NULL; 2048 /* if this is not something we're looking for, skip it. */ 2049 while (cp && *cp) { 2050 if (*cp == ' ' || *cp == '\t') { 2051 cp++; 2052 continue; 2053 } 2054 tname = cp; 2055 if (cname == NULL) 2056 cname = cp; 2057 if ((cp = strpbrk(cp, " \t")) != NULL) 2058 *cp++ = '\0'; 2059 if (strcasecmp(name, tname) == 0) 2060 goto found; 2061 } 2062 goto again; 2063 2064found: 2065 /* we should not glob socktype/protocol here */ 2066 memset(&hints, 0, sizeof(hints)); 2067 hints.ai_family = pai->ai_family; 2068 hints.ai_socktype = SOCK_DGRAM; 2069 hints.ai_protocol = 0; 2070 hints.ai_flags = AI_NUMERICHOST; 2071 error = getaddrinfo(addr, "0", &hints, &res0); 2072 if (error) 2073 goto again; 2074#ifdef FILTER_V4MAPPED 2075 /* XXX should check all items in the chain */ 2076 if (res0->ai_family == AF_INET6 && 2077 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2078 freeaddrinfo(res0); 2079 goto again; 2080 } 2081#endif 2082 for (res = res0; res; res = res->ai_next) { 2083 /* cover it up */ 2084 res->ai_flags = pai->ai_flags; 2085 res->ai_socktype = pai->ai_socktype; 2086 res->ai_protocol = pai->ai_protocol; 2087 2088 if (pai->ai_flags & AI_CANONNAME) { 2089 if (get_canonname(pai, res, cname) != 0) { 2090 freeaddrinfo(res0); 2091 goto again; 2092 } 2093 } 2094 } 2095 return res0; 2096} 2097 2098/*ARGSUSED*/ 2099static int 2100_files_getaddrinfo(rv, cb_data, ap) 2101 void *rv; 2102 void *cb_data; 2103 va_list ap; 2104{ 2105 const char *name; 2106 const struct addrinfo *pai; 2107 struct addrinfo sentinel, *cur; 2108 struct addrinfo *p; 2109 FILE *hostf = NULL; 2110 2111 name = va_arg(ap, char *); 2112 pai = va_arg(ap, struct addrinfo *); 2113 2114 memset(&sentinel, 0, sizeof(sentinel)); 2115 cur = &sentinel; 2116 2117 _sethtent(&hostf); 2118 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2119 cur->ai_next = p; 2120 while (cur && cur->ai_next) 2121 cur = cur->ai_next; 2122 } 2123 _endhtent(&hostf); 2124 2125 *((struct addrinfo **)rv) = sentinel.ai_next; 2126 if (sentinel.ai_next == NULL) 2127 return NS_NOTFOUND; 2128 return NS_SUCCESS; 2129} 2130 2131#ifdef YP 2132/*ARGSUSED*/ 2133static struct addrinfo * 2134_yphostent(line, pai) 2135 char *line; 2136 const struct addrinfo *pai; 2137{ 2138 struct addrinfo sentinel, *cur; 2139 struct addrinfo hints, *res, *res0; 2140 int error; 2141 char *p = line; 2142 const char *addr, *canonname; 2143 char *nextline; 2144 char *cp; 2145 2146 addr = canonname = NULL; 2147 2148 memset(&sentinel, 0, sizeof(sentinel)); 2149 cur = &sentinel; 2150 2151nextline: 2152 /* terminate line */ 2153 cp = strchr(p, '\n'); 2154 if (cp) { 2155 *cp++ = '\0'; 2156 nextline = cp; 2157 } else 2158 nextline = NULL; 2159 2160 cp = strpbrk(p, " \t"); 2161 if (cp == NULL) { 2162 if (canonname == NULL) 2163 return (NULL); 2164 else 2165 goto done; 2166 } 2167 *cp++ = '\0'; 2168 2169 addr = p; 2170 2171 while (cp && *cp) { 2172 if (*cp == ' ' || *cp == '\t') { 2173 cp++; 2174 continue; 2175 } 2176 if (!canonname) 2177 canonname = cp; 2178 if ((cp = strpbrk(cp, " \t")) != NULL) 2179 *cp++ = '\0'; 2180 } 2181 2182 hints = *pai; 2183 hints.ai_flags = AI_NUMERICHOST; 2184 error = getaddrinfo(addr, NULL, &hints, &res0); 2185 if (error == 0) { 2186 for (res = res0; res; res = res->ai_next) { 2187 /* cover it up */ 2188 res->ai_flags = pai->ai_flags; 2189 2190 if (pai->ai_flags & AI_CANONNAME) 2191 (void)get_canonname(pai, res, canonname); 2192 } 2193 } else 2194 res0 = NULL; 2195 if (res0) { 2196 cur->ai_next = res0; 2197 while (cur && cur->ai_next) 2198 cur = cur->ai_next; 2199 } 2200 2201 if (nextline) { 2202 p = nextline; 2203 goto nextline; 2204 } 2205 2206done: 2207 return sentinel.ai_next; 2208} 2209 2210/*ARGSUSED*/ 2211static int 2212_yp_getaddrinfo(rv, cb_data, ap) 2213 void *rv; 2214 void *cb_data; 2215 va_list ap; 2216{ 2217 struct addrinfo sentinel, *cur; 2218 struct addrinfo *ai = NULL; 2219 char *ypbuf; 2220 int ypbuflen, r; 2221 const char *name; 2222 const struct addrinfo *pai; 2223 char *ypdomain; 2224 2225 if (_yp_check(&ypdomain) == 0) 2226 return NS_UNAVAIL; 2227 2228 name = va_arg(ap, char *); 2229 pai = va_arg(ap, const struct addrinfo *); 2230 2231 memset(&sentinel, 0, sizeof(sentinel)); 2232 cur = &sentinel; 2233 2234 /* hosts.byname is only for IPv4 (Solaris8) */ 2235 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2236 r = yp_match(ypdomain, "hosts.byname", name, 2237 (int)strlen(name), &ypbuf, &ypbuflen); 2238 if (r == 0) { 2239 struct addrinfo ai4; 2240 2241 ai4 = *pai; 2242 ai4.ai_family = AF_INET; 2243 ai = _yphostent(ypbuf, &ai4); 2244 if (ai) { 2245 cur->ai_next = ai; 2246 while (cur && cur->ai_next) 2247 cur = cur->ai_next; 2248 } 2249 free(ypbuf); 2250 } 2251 } 2252 2253 /* ipnodes.byname can hold both IPv4/v6 */ 2254 r = yp_match(ypdomain, "ipnodes.byname", name, 2255 (int)strlen(name), &ypbuf, &ypbuflen); 2256 if (r == 0) { 2257 ai = _yphostent(ypbuf, pai); 2258 if (ai) 2259 cur->ai_next = ai; 2260 free(ypbuf); 2261 } 2262 2263 if (sentinel.ai_next == NULL) { 2264 h_errno = HOST_NOT_FOUND; 2265 return NS_NOTFOUND; 2266 } 2267 *((struct addrinfo **)rv) = sentinel.ai_next; 2268 return NS_SUCCESS; 2269} 2270#endif 2271 2272/* resolver logic */ 2273 2274extern const char *_res_hostalias(const char *, char *, size_t); 2275 2276/* 2277 * Formulate a normal query, send, and await answer. 2278 * Returned answer is placed in supplied buffer "answer". 2279 * Perform preliminary check of answer, returning success only 2280 * if no error is indicated and the answer count is nonzero. 2281 * Return the size of the response on success, -1 on error. 2282 * Error number is left in h_errno. 2283 * 2284 * Caller must parse answer and determine whether it answers the question. 2285 */ 2286static int 2287res_queryN(name, target) 2288 const char *name; /* domain name */ 2289 struct res_target *target; 2290{ 2291 u_char *buf; 2292 HEADER *hp; 2293 int n; 2294 struct res_target *t; 2295 int rcode; 2296 int ancount; 2297 2298 rcode = NOERROR; 2299 ancount = 0; 2300 2301 buf = malloc(MAXPACKET); 2302 if (!buf) { 2303 h_errno = NETDB_INTERNAL; 2304 return -1; 2305 } 2306 2307 for (t = target; t; t = t->next) { 2308 int class, type; 2309 u_char *answer; 2310 int anslen; 2311 2312 hp = (HEADER *)(void *)t->answer; 2313 hp->rcode = NOERROR; /* default */ 2314 2315 /* make it easier... */ 2316 class = t->qclass; 2317 type = t->qtype; 2318 answer = t->answer; 2319 anslen = t->anslen; 2320#ifdef DEBUG 2321 if (_res.options & RES_DEBUG) 2322 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2323#endif 2324 2325 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, 2326 buf, MAXPACKET); 2327 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) 2328 n = res_opt(n, buf, MAXPACKET, anslen); 2329 if (n <= 0) { 2330#ifdef DEBUG 2331 if (_res.options & RES_DEBUG) 2332 printf(";; res_query: mkquery failed\n"); 2333#endif 2334 free(buf); 2335 h_errno = NO_RECOVERY; 2336 return (n); 2337 } 2338 n = res_send(buf, n, answer, anslen); 2339#if 0 2340 if (n < 0) { 2341#ifdef DEBUG 2342 if (_res.options & RES_DEBUG) 2343 printf(";; res_query: send error\n"); 2344#endif 2345 free(buf); 2346 h_errno = TRY_AGAIN; 2347 return (n); 2348 } 2349#endif 2350 2351 if (n < 0 || n > anslen) 2352 hp->rcode = FORMERR; /* XXX not very informative */ 2353 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2354 rcode = hp->rcode; /* record most recent error */ 2355#ifdef DEBUG 2356 if (_res.options & RES_DEBUG) 2357 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2358 ntohs(hp->ancount)); 2359#endif 2360 continue; 2361 } 2362 2363 ancount += ntohs(hp->ancount); 2364 2365 t->n = n; 2366 } 2367 2368 free(buf); 2369 2370 if (ancount == 0) { 2371 switch (rcode) { 2372 case NXDOMAIN: 2373 h_errno = HOST_NOT_FOUND; 2374 break; 2375 case SERVFAIL: 2376 h_errno = TRY_AGAIN; 2377 break; 2378 case NOERROR: 2379 h_errno = NO_DATA; 2380 break; 2381 case FORMERR: 2382 case NOTIMP: 2383 case REFUSED: 2384 default: 2385 h_errno = NO_RECOVERY; 2386 break; 2387 } 2388 return (-1); 2389 } 2390 return (ancount); 2391} 2392 2393/* 2394 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2395 * Return the size of the response on success, -1 on error. 2396 * If enabled, implement search rules until answer or unrecoverable failure 2397 * is detected. Error code, if any, is left in h_errno. 2398 */ 2399static int 2400res_searchN(name, target) 2401 const char *name; /* domain name */ 2402 struct res_target *target; 2403{ 2404 const char *cp, * const *domain; 2405 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2406 u_int dots; 2407 int trailing_dot, ret, saved_herrno; 2408 int got_nodata = 0, got_servfail = 0, root_on_list = 0; 2409 int tried_as_is = 0; 2410 int searched = 0; 2411 char abuf[MAXDNAME]; 2412 2413 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2414 h_errno = NETDB_INTERNAL; 2415 return (-1); 2416 } 2417 2418 errno = 0; 2419 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 2420 dots = 0; 2421 for (cp = name; *cp; cp++) 2422 dots += (*cp == '.'); 2423 trailing_dot = 0; 2424 if (cp > name && *--cp == '.') 2425 trailing_dot++; 2426 2427 /* 2428 * if there aren't any dots, it could be a user-level alias 2429 */ 2430 if (!dots && (cp = _res_hostalias(name, abuf, sizeof(abuf))) != NULL) 2431 return (res_queryN(cp, target)); 2432 2433 /* 2434 * If there are enough dots in the name, let's just give it a 2435 * try 'as is'. The threshold can be set with the "ndots" option. 2436 * Also, query 'as is', if there is a trailing dot in the name. 2437 */ 2438 saved_herrno = -1; 2439 if (dots >= _res.ndots || trailing_dot) { 2440 ret = res_querydomainN(name, NULL, target); 2441 if (ret > 0 || trailing_dot) 2442 return (ret); 2443 if (errno == ECONNREFUSED) { 2444 h_errno = TRY_AGAIN; 2445 return (-1); 2446 } 2447 switch (h_errno) { 2448 case NO_DATA: 2449 case HOST_NOT_FOUND: 2450 break; 2451 default: 2452 return (-1); 2453 } 2454 saved_herrno = h_errno; 2455 tried_as_is++; 2456 } 2457 2458 /* 2459 * We do at least one level of search if 2460 * - there is no dot and RES_DEFNAME is set, or 2461 * - there is at least one dot, there is no trailing dot, 2462 * and RES_DNSRCH is set. 2463 */ 2464 if ((!dots && (_res.options & RES_DEFNAMES)) || 2465 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { 2466 int done = 0; 2467 2468 for (domain = (const char * const *)_res.dnsrch; 2469 *domain && !done; 2470 domain++) { 2471 searched = 1; 2472 2473 if (domain[0][0] == '\0' || 2474 (domain[0][0] == '.' && domain[0][1] == '\0')) 2475 root_on_list++; 2476 2477 if (root_on_list && tried_as_is) 2478 continue; 2479 2480 ret = res_querydomainN(name, *domain, target); 2481 if (ret > 0) 2482 return (ret); 2483 2484 /* 2485 * If no server present, give up. 2486 * If name isn't found in this domain, 2487 * keep trying higher domains in the search list 2488 * (if that's enabled). 2489 * On a NO_DATA error, keep trying, otherwise 2490 * a wildcard entry of another type could keep us 2491 * from finding this entry higher in the domain. 2492 * If we get some other error (negative answer or 2493 * server failure), then stop searching up, 2494 * but try the input name below in case it's 2495 * fully-qualified. 2496 */ 2497 if (errno == ECONNREFUSED) { 2498 h_errno = TRY_AGAIN; 2499 return (-1); 2500 } 2501 2502 switch (h_errno) { 2503 case NO_DATA: 2504 got_nodata++; 2505 /* FALLTHROUGH */ 2506 case HOST_NOT_FOUND: 2507 /* keep trying */ 2508 break; 2509 case TRY_AGAIN: 2510 if (hp->rcode == SERVFAIL) { 2511 /* try next search element, if any */ 2512 got_servfail++; 2513 break; 2514 } 2515 /* FALLTHROUGH */ 2516 default: 2517 /* anything else implies that we're done */ 2518 done++; 2519 } 2520 /* 2521 * if we got here for some reason other than DNSRCH, 2522 * we only wanted one iteration of the loop, so stop. 2523 */ 2524 if (!(_res.options & RES_DNSRCH)) 2525 done++; 2526 } 2527 } 2528 2529 switch (h_errno) { 2530 case NO_DATA: 2531 case HOST_NOT_FOUND: 2532 break; 2533 default: 2534 goto giveup; 2535 } 2536 2537 /* 2538 * If the query has not already been tried as is then try it 2539 * unless RES_NOTLDQUERY is set and there were no dots. 2540 */ 2541 if ((dots || !searched || !(_res.options & RES_NOTLDQUERY)) && 2542 !(tried_as_is || root_on_list)) { 2543 ret = res_querydomainN(name, NULL, target); 2544 if (ret > 0) 2545 return (ret); 2546 } 2547 2548 /* 2549 * if we got here, we didn't satisfy the search. 2550 * if we did an initial full query, return that query's h_errno 2551 * (note that we wouldn't be here if that query had succeeded). 2552 * else if we ever got a nodata, send that back as the reason. 2553 * else send back meaningless h_errno, that being the one from 2554 * the last DNSRCH we did. 2555 */ 2556giveup: 2557 if (saved_herrno != -1) 2558 h_errno = saved_herrno; 2559 else if (got_nodata) 2560 h_errno = NO_DATA; 2561 else if (got_servfail) 2562 h_errno = TRY_AGAIN; 2563 return (-1); 2564} 2565 2566/* 2567 * Perform a call on res_query on the concatenation of name and domain, 2568 * removing a trailing dot from name if domain is NULL. 2569 */ 2570static int 2571res_querydomainN(name, domain, target) 2572 const char *name, *domain; 2573 struct res_target *target; 2574{ 2575 char nbuf[MAXDNAME]; 2576 const char *longname = nbuf; 2577 size_t n, d; 2578 2579#ifdef DEBUG 2580 if (_res.options & RES_DEBUG) 2581 printf(";; res_querydomain(%s, %s)\n", 2582 name, domain?domain:"<Nil>"); 2583#endif 2584 if (domain == NULL) { 2585 /* 2586 * Check for trailing '.'; 2587 * copy without '.' if present. 2588 */ 2589 n = strlen(name); 2590 if (n >= MAXDNAME) { 2591 h_errno = NO_RECOVERY; 2592 return (-1); 2593 } 2594 if (n > 0 && name[--n] == '.') { 2595 strncpy(nbuf, name, n); 2596 nbuf[n] = '\0'; 2597 } else 2598 longname = name; 2599 } else { 2600 n = strlen(name); 2601 d = strlen(domain); 2602 if (n + d + 1 >= MAXDNAME) { 2603 h_errno = NO_RECOVERY; 2604 return (-1); 2605 } 2606 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2607 } 2608 return (res_queryN(longname, target)); 2609} 2610