getaddrinfo.c revision 121747
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 121747 2003-10-30 17:36:53Z 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 <netinet6/in6_var.h> /* XXX */ 79#endif 80#include <arpa/inet.h> 81#include <arpa/nameser.h> 82#include <rpc/rpc.h> 83#include <rpcsvc/yp_prot.h> 84#include <rpcsvc/ypclnt.h> 85#include <netdb.h> 86#include <pthread.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 int 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 str_isnumber(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 **); 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 int comp_dst(const void *, const void *); 251#ifdef INET6 252static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 253#endif 254static int gai_addr2scopetype(struct sockaddr *); 255 256static int explore_fqdn(const struct addrinfo *, const char *, 257 const char *, struct addrinfo **); 258 259static int reorder(struct addrinfo *); 260static int get_addrselectpolicy(struct policyhead *); 261static void free_addrselectpolicy(struct policyhead *); 262static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 263 struct policyhead *); 264 265static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 266 const struct addrinfo *); 267#if defined(RESOLVSORT) 268static int addr4sort(struct addrinfo *); 269#endif 270static int _dns_getaddrinfo(void *, void *, va_list); 271static void _sethtent(void); 272static void _endhtent(void); 273static struct addrinfo *_gethtent(const char *, const struct addrinfo *); 274static int _files_getaddrinfo(void *, void *, va_list); 275#ifdef YP 276static struct addrinfo *_yphostent(char *, const struct addrinfo *); 277static int _yp_getaddrinfo(void *, void *, va_list); 278#endif 279 280static int res_queryN(const char *, struct res_target *); 281static int res_searchN(const char *, struct res_target *); 282static int res_querydomainN(const char *, const char *, 283 struct res_target *); 284 285static struct ai_errlist { 286 const char *str; 287 int code; 288} ai_errlist[] = { 289 { "Success", 0, }, 290 { "Temporary failure in name resolution", EAI_AGAIN, }, 291 { "Invalid value for ai_flags", EAI_BADFLAGS, }, 292 { "Non-recoverable failure in name resolution", EAI_FAIL, }, 293 { "ai_family not supported", EAI_FAMILY, }, 294 { "Memory allocation failure", EAI_MEMORY, }, 295 { "hostname nor servname provided, or not known", EAI_NONAME, }, 296 { "servname not supported for ai_socktype", EAI_SERVICE, }, 297 { "ai_socktype not supported", EAI_SOCKTYPE, }, 298 { "System error returned in errno", EAI_SYSTEM, }, 299 { "Invalid value for hints", EAI_BADHINTS, }, 300 { "Resolved protocol is unknown", EAI_PROTOCOL, }, 301 /* backward compatibility with userland code prior to 2553bis-02 */ 302 { "Address family for hostname not supported", 1, }, 303 { "No address associated with hostname", 7, }, 304 { NULL, -1, }, 305}; 306 307/* 308 * XXX: Our res_*() is not thread-safe. So, we share lock between 309 * getaddrinfo() and getipnodeby*(). Still, we cannot use 310 * getaddrinfo() and getipnodeby*() in conjunction with other 311 * functions which call res_*(). 312 */ 313pthread_mutex_t __getaddrinfo_thread_lock = PTHREAD_MUTEX_INITIALIZER; 314#define THREAD_LOCK() \ 315 if (__isthreaded) _pthread_mutex_lock(&__getaddrinfo_thread_lock); 316#define THREAD_UNLOCK() \ 317 if (__isthreaded) _pthread_mutex_unlock(&__getaddrinfo_thread_lock); 318 319/* XXX macros that make external reference is BAD. */ 320 321#define GET_AI(ai, afd, addr) \ 322do { \ 323 /* external reference: pai, error, and label free */ \ 324 (ai) = get_ai(pai, (afd), (addr)); \ 325 if ((ai) == NULL) { \ 326 error = EAI_MEMORY; \ 327 goto free; \ 328 } \ 329} while (/*CONSTCOND*/0) 330 331#define GET_PORT(ai, serv) \ 332do { \ 333 /* external reference: error and label free */ \ 334 error = get_port((ai), (serv), 0); \ 335 if (error != 0) \ 336 goto free; \ 337} while (/*CONSTCOND*/0) 338 339#define GET_CANONNAME(ai, str) \ 340do { \ 341 /* external reference: pai, error and label free */ \ 342 error = get_canonname(pai, (ai), (str)); \ 343 if (error != 0) \ 344 goto free; \ 345} while (/*CONSTCOND*/0) 346 347#define ERR(err) \ 348do { \ 349 /* external reference: error, and label bad */ \ 350 error = (err); \ 351 goto bad; \ 352 /*NOTREACHED*/ \ 353} while (/*CONSTCOND*/0) 354 355#define MATCH_FAMILY(x, y, w) \ 356 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 357#define MATCH(x, y, w) \ 358 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 359 360char * 361gai_strerror(ecode) 362 int ecode; 363{ 364 struct ai_errlist *p; 365 366 for (p = ai_errlist; p->str; p++) { 367 if (p->code == ecode) 368 return (char *)p->str; 369 } 370 return "Unknown error"; 371} 372 373void 374freeaddrinfo(ai) 375 struct addrinfo *ai; 376{ 377 struct addrinfo *next; 378 379 do { 380 next = ai->ai_next; 381 if (ai->ai_canonname) 382 free(ai->ai_canonname); 383 /* no need to free(ai->ai_addr) */ 384 free(ai); 385 ai = next; 386 } while (ai); 387} 388 389static int 390str_isnumber(p) 391 const char *p; 392{ 393 char *ep; 394 395 if (*p == '\0') 396 return NO; 397 ep = NULL; 398 errno = 0; 399 (void)strtoul(p, &ep, 10); 400 if (errno == 0 && ep && *ep == '\0') 401 return YES; 402 else 403 return NO; 404} 405 406int 407getaddrinfo(hostname, servname, hints, res) 408 const char *hostname, *servname; 409 const struct addrinfo *hints; 410 struct addrinfo **res; 411{ 412 struct addrinfo sentinel; 413 struct addrinfo *cur; 414 int error = 0; 415 struct addrinfo ai; 416 struct addrinfo ai0; 417 struct addrinfo *pai; 418 const struct explore *ex; 419 int numeric = 0; 420 421 memset(&sentinel, 0, sizeof(sentinel)); 422 cur = &sentinel; 423 pai = &ai; 424 pai->ai_flags = 0; 425 pai->ai_family = PF_UNSPEC; 426 pai->ai_socktype = ANY; 427 pai->ai_protocol = ANY; 428 pai->ai_addrlen = 0; 429 pai->ai_canonname = NULL; 430 pai->ai_addr = NULL; 431 pai->ai_next = NULL; 432 433 if (hostname == NULL && servname == NULL) 434 return EAI_NONAME; 435 if (hints) { 436 /* error check for hints */ 437 if (hints->ai_addrlen || hints->ai_canonname || 438 hints->ai_addr || hints->ai_next) 439 ERR(EAI_BADHINTS); /* xxx */ 440 if (hints->ai_flags & ~AI_MASK) 441 ERR(EAI_BADFLAGS); 442 switch (hints->ai_family) { 443 case PF_UNSPEC: 444 case PF_INET: 445#ifdef INET6 446 case PF_INET6: 447#endif 448 break; 449 default: 450 ERR(EAI_FAMILY); 451 } 452 memcpy(pai, hints, sizeof(*pai)); 453 454 /* 455 * if both socktype/protocol are specified, check if they 456 * are meaningful combination. 457 */ 458 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 459 for (ex = explore; ex->e_af >= 0; ex++) { 460 if (pai->ai_family != ex->e_af) 461 continue; 462 if (ex->e_socktype == ANY) 463 continue; 464 if (ex->e_protocol == ANY) 465 continue; 466 if (pai->ai_socktype == ex->e_socktype && 467 pai->ai_protocol != ex->e_protocol) { 468 ERR(EAI_BADHINTS); 469 } 470 } 471 } 472 } 473 474 /* 475 * post-2553: AI_ALL and AI_V4MAPPED are effective only against 476 * AF_INET6 query. They need to be ignored if specified in other 477 * occassions. 478 */ 479 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 480 case AI_V4MAPPED: 481 case AI_ALL | AI_V4MAPPED: 482 if (pai->ai_family != AF_INET6) 483 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 484 break; 485 case AI_ALL: 486#if 1 487 /* illegal */ 488 ERR(EAI_BADFLAGS); 489#else 490 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 491#endif 492 break; 493 } 494 495 /* 496 * check for special cases. (1) numeric servname is disallowed if 497 * socktype/protocol are left unspecified. (2) servname is disallowed 498 * for raw and other inet{,6} sockets. 499 */ 500 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 501#ifdef PF_INET6 502 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 503#endif 504 ) { 505 ai0 = *pai; /* backup *pai */ 506 507 if (pai->ai_family == PF_UNSPEC) { 508#ifdef PF_INET6 509 pai->ai_family = PF_INET6; 510#else 511 pai->ai_family = PF_INET; 512#endif 513 } 514 error = get_portmatch(pai, servname); 515 if (error) 516 ERR(error); 517 518 *pai = ai0; 519 } 520 521 ai0 = *pai; 522 523 /* NULL hostname, or numeric hostname */ 524 for (ex = explore; ex->e_af >= 0; ex++) { 525 *pai = ai0; 526 527 /* PF_UNSPEC entries are prepared for DNS queries only */ 528 if (ex->e_af == PF_UNSPEC) 529 continue; 530 531 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 532 continue; 533 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 534 continue; 535 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 536 continue; 537 538 if (pai->ai_family == PF_UNSPEC) 539 pai->ai_family = ex->e_af; 540 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 541 pai->ai_socktype = ex->e_socktype; 542 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 543 pai->ai_protocol = ex->e_protocol; 544 545 if (hostname == NULL) 546 error = explore_null(pai, servname, &cur->ai_next); 547 else 548 error = explore_numeric_scope(pai, hostname, servname, &cur->ai_next); 549 550 if (error) 551 goto free; 552 553 while (cur && cur->ai_next) 554 cur = cur->ai_next; 555 } 556 557 /* 558 * XXX 559 * If numreic representation of AF1 can be interpreted as FQDN 560 * representation of AF2, we need to think again about the code below. 561 */ 562 if (sentinel.ai_next) { 563 numeric = 1; 564 goto good; 565 } 566 567 if (hostname == NULL) 568 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 569 if (pai->ai_flags & AI_NUMERICHOST) 570 ERR(EAI_NONAME); 571 572 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 573 ERR(EAI_FAIL); 574 575 /* 576 * hostname as alphabetical name. 577 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 578 * outer loop by AFs. 579 */ 580 for (ex = explore; ex->e_af >= 0; ex++) { 581 *pai = ai0; 582 583 /* require exact match for family field */ 584 if (pai->ai_family != ex->e_af) 585 continue; 586 587 if (!MATCH(pai->ai_socktype, ex->e_socktype, 588 WILD_SOCKTYPE(ex))) { 589 continue; 590 } 591 if (!MATCH(pai->ai_protocol, ex->e_protocol, 592 WILD_PROTOCOL(ex))) { 593 continue; 594 } 595 596 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 597 pai->ai_socktype = ex->e_socktype; 598 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 599 pai->ai_protocol = ex->e_protocol; 600 601 error = explore_fqdn(pai, hostname, servname, 602 &cur->ai_next); 603 604 while (cur && cur->ai_next) 605 cur = cur->ai_next; 606 } 607 608 /* XXX inhibit errors if we have the result */ 609 if (sentinel.ai_next) 610 error = 0; 611 612good: 613 /* 614 * ensure we return either: 615 * - error == 0, non-NULL *res 616 * - error != 0, NULL *res 617 */ 618 if (error == 0) { 619 if (sentinel.ai_next) { 620 /* 621 * If the returned entry is for an active connection, 622 * and the given name is not numeric, reorder the 623 * list, so that the application would try the list 624 * in the most efficient order. 625 */ 626 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 627 if (!numeric) 628 (void)reorder(&sentinel); 629 } 630 *res = sentinel.ai_next; 631 return SUCCESS; 632 } else 633 error = EAI_FAIL; 634 } 635free: 636bad: 637 if (sentinel.ai_next) 638 freeaddrinfo(sentinel.ai_next); 639 *res = NULL; 640 return error; 641} 642 643static int 644reorder(sentinel) 645 struct addrinfo *sentinel; 646{ 647 struct addrinfo *ai, **aip; 648 struct ai_order *aio; 649 int i, n; 650 struct policyhead policyhead; 651 652 /* count the number of addrinfo elements for sorting. */ 653 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 654 ; 655 656 /* 657 * If the number is small enough, we can skip the reordering process. 658 */ 659 if (n <= 1) 660 return(n); 661 662 /* allocate a temporary array for sort and initialization of it. */ 663 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 664 return(n); /* give up reordering */ 665 memset(aio, 0, sizeof(*aio) * n); 666 667 /* retrieve address selection policy from the kernel */ 668 TAILQ_INIT(&policyhead); 669 if (!get_addrselectpolicy(&policyhead)) { 670 /* no policy is installed into kernel, we don't sort. */ 671 free(aio); 672 return (n); 673 } 674 675 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 676 aio[i].aio_ai = ai; 677 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 678 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 679 &policyhead); 680 } 681 682 /* perform sorting. */ 683 qsort(aio, n, sizeof(*aio), comp_dst); 684 685 /* reorder the addrinfo chain. */ 686 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 687 *aip = aio[i].aio_ai; 688 aip = &aio[i].aio_ai->ai_next; 689 } 690 *aip = NULL; 691 692 /* cleanup and return */ 693 free(aio); 694 free_addrselectpolicy(&policyhead); 695 return(n); 696} 697 698static int 699get_addrselectpolicy(head) 700 struct policyhead *head; 701{ 702#ifdef INET6 703 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 704 size_t l; 705 char *buf; 706 struct in6_addrpolicy *pol, *ep; 707 708 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 709 return (0); 710 if ((buf = malloc(l)) == NULL) 711 return (0); 712 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 713 free(buf); 714 return (0); 715 } 716 717 ep = (struct in6_addrpolicy *)(buf + l); 718 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 719 struct policyqueue *new; 720 721 if ((new = malloc(sizeof(*new))) == NULL) { 722 free_addrselectpolicy(head); /* make the list empty */ 723 break; 724 } 725 new->pc_policy = *pol; 726 TAILQ_INSERT_TAIL(head, new, pc_entry); 727 } 728 729 free(buf); 730 return (1); 731#else 732 return (0); 733#endif 734} 735 736static void 737free_addrselectpolicy(head) 738 struct policyhead *head; 739{ 740 struct policyqueue *ent, *nent; 741 742 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 743 nent = TAILQ_NEXT(ent, pc_entry); 744 TAILQ_REMOVE(head, ent, pc_entry); 745 free(ent); 746 } 747} 748 749static struct policyqueue * 750match_addrselectpolicy(addr, head) 751 struct sockaddr *addr; 752 struct policyhead *head; 753{ 754#ifdef INET6 755 struct policyqueue *ent, *bestent = NULL; 756 struct in6_addrpolicy *pol; 757 int matchlen, bestmatchlen = -1; 758 u_char *mp, *ep, *k, *p, m; 759 struct sockaddr_in6 key; 760 761 switch(addr->sa_family) { 762 case AF_INET6: 763 key = *(struct sockaddr_in6 *)addr; 764 break; 765 case AF_INET: 766 /* convert the address into IPv4-mapped IPv6 address. */ 767 memset(&key, 0, sizeof(key)); 768 key.sin6_family = AF_INET6; 769 key.sin6_len = sizeof(key); 770 key.sin6_addr.s6_addr[10] = 0xff; 771 key.sin6_addr.s6_addr[11] = 0xff; 772 memcpy(&key.sin6_addr.s6_addr[12], 773 &((struct sockaddr_in *)addr)->sin_addr, 4); 774 break; 775 default: 776 return(NULL); 777 } 778 779 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 780 pol = &ent->pc_policy; 781 matchlen = 0; 782 783 mp = (u_char *)&pol->addrmask.sin6_addr; 784 ep = mp + 16; /* XXX: scope field? */ 785 k = (u_char *)&key.sin6_addr; 786 p = (u_char *)&pol->addr.sin6_addr; 787 for (; mp < ep && *mp; mp++, k++, p++) { 788 m = *mp; 789 if ((*k & m) != *p) 790 goto next; /* not match */ 791 if (m == 0xff) /* short cut for a typical case */ 792 matchlen += 8; 793 else { 794 while (m >= 0x80) { 795 matchlen++; 796 m <<= 1; 797 } 798 } 799 } 800 801 /* matched. check if this is better than the current best. */ 802 if (matchlen > bestmatchlen) { 803 bestent = ent; 804 bestmatchlen = matchlen; 805 } 806 807 next: 808 continue; 809 } 810 811 return(bestent); 812#else 813 return(NULL); 814#endif 815 816} 817 818static int 819comp_dst(arg1, arg2) 820 const void *arg1, *arg2; 821{ 822 const struct ai_order *dst1 = arg1, *dst2 = arg2; 823 824 /* 825 * Rule 1: Avoid unusable destinations. 826 * XXX: we currently do not consider if an appropriate route exists. 827 */ 828 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 829 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 830 return(-1); 831 } 832 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 833 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 834 return(1); 835 } 836 837 /* Rule 2: Prefer matching scope. */ 838 if (dst1->aio_dstscope == dst1->aio_srcscope && 839 dst2->aio_dstscope != dst2->aio_srcscope) { 840 return(-1); 841 } 842 if (dst1->aio_dstscope != dst1->aio_srcscope && 843 dst2->aio_dstscope == dst2->aio_srcscope) { 844 return(1); 845 } 846 847 /* Rule 3: Avoid deprecated addresses. */ 848 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 849 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 850 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 851 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 852 return(-1); 853 } 854 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 855 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 856 return(1); 857 } 858 } 859 860 /* Rule 4: Prefer home addresses. */ 861 /* XXX: not implemented yet */ 862 863 /* Rule 5: Prefer matching label. */ 864#ifdef INET6 865 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 866 dst1->aio_srcpolicy->pc_policy.label == 867 dst1->aio_dstpolicy->pc_policy.label && 868 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 869 dst2->aio_srcpolicy->pc_policy.label != 870 dst2->aio_dstpolicy->pc_policy.label)) { 871 return(-1); 872 } 873 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 874 dst2->aio_srcpolicy->pc_policy.label == 875 dst2->aio_dstpolicy->pc_policy.label && 876 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 877 dst1->aio_srcpolicy->pc_policy.label != 878 dst1->aio_dstpolicy->pc_policy.label)) { 879 return(1); 880 } 881#endif 882 883 /* Rule 6: Prefer higher precedence. */ 884#ifdef INET6 885 if (dst1->aio_dstpolicy && 886 (dst2->aio_dstpolicy == NULL || 887 dst1->aio_dstpolicy->pc_policy.preced > 888 dst2->aio_dstpolicy->pc_policy.preced)) { 889 return(-1); 890 } 891 if (dst2->aio_dstpolicy && 892 (dst1->aio_dstpolicy == NULL || 893 dst2->aio_dstpolicy->pc_policy.preced > 894 dst1->aio_dstpolicy->pc_policy.preced)) { 895 return(1); 896 } 897#endif 898 899 /* Rule 7: Prefer native transport. */ 900 /* XXX: not implemented yet */ 901 902 /* Rule 8: Prefer smaller scope. */ 903 if (dst1->aio_dstscope >= 0 && 904 dst1->aio_dstscope < dst2->aio_dstscope) { 905 return(-1); 906 } 907 if (dst2->aio_dstscope >= 0 && 908 dst2->aio_dstscope < dst1->aio_dstscope) { 909 return(1); 910 } 911 912 /* 913 * Rule 9: Use longest matching prefix. 914 * We compare the match length in a same AF only. 915 */ 916 if (dst1->aio_ai->ai_addr->sa_family == 917 dst2->aio_ai->ai_addr->sa_family) { 918 if (dst1->aio_matchlen > dst2->aio_matchlen) { 919 return(-1); 920 } 921 if (dst1->aio_matchlen < dst2->aio_matchlen) { 922 return(1); 923 } 924 } 925 926 /* Rule 10: Otherwise, leave the order unchanged. */ 927 return(-1); 928} 929 930/* 931 * Copy from scope.c. 932 * XXX: we should standardize the functions and link them as standard 933 * library. 934 */ 935static int 936gai_addr2scopetype(sa) 937 struct sockaddr *sa; 938{ 939#ifdef INET6 940 struct sockaddr_in6 *sa6; 941#endif 942 struct sockaddr_in *sa4; 943 944 switch(sa->sa_family) { 945#ifdef INET6 946 case AF_INET6: 947 sa6 = (struct sockaddr_in6 *)sa; 948 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 949 /* just use the scope field of the multicast address */ 950 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 951 } 952 /* 953 * Unicast addresses: map scope type to corresponding scope 954 * value defined for multcast addresses. 955 * XXX: hardcoded scope type values are bad... 956 */ 957 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 958 return(1); /* node local scope */ 959 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 960 return(2); /* link-local scope */ 961 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 962 return(5); /* site-local scope */ 963 return(14); /* global scope */ 964 break; 965#endif 966 case AF_INET: 967 /* 968 * IPv4 pseudo scoping according to RFC 3484. 969 */ 970 sa4 = (struct sockaddr_in *)sa; 971 /* IPv4 autoconfiguration addresses have link-local scope. */ 972 if (((u_char *)&sa4->sin_addr)[0] == 169 && 973 ((u_char *)&sa4->sin_addr)[1] == 254) 974 return(2); 975 /* Private addresses have site-local scope. */ 976 if (((u_char *)&sa4->sin_addr)[0] == 10 || 977 (((u_char *)&sa4->sin_addr)[0] == 172 && 978 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 979 (((u_char *)&sa4->sin_addr)[0] == 192 && 980 ((u_char *)&sa4->sin_addr)[1] == 168)) 981 return(5); 982 /* Loopback addresses have link-local scope. */ 983 if (((u_char *)&sa4->sin_addr)[0] == 127) 984 return(2); 985 return(14); 986 break; 987 default: 988 errno = EAFNOSUPPORT; /* is this a good error? */ 989 return(-1); 990 } 991} 992 993/* 994 * hostname == NULL. 995 * passive socket -> anyaddr (0.0.0.0 or ::) 996 * non-passive socket -> localhost (127.0.0.1 or ::1) 997 */ 998static int 999explore_null(pai, servname, res) 1000 const struct addrinfo *pai; 1001 const char *servname; 1002 struct addrinfo **res; 1003{ 1004 int s; 1005 const struct afd *afd; 1006 struct addrinfo *cur; 1007 struct addrinfo sentinel; 1008 int error; 1009 1010 *res = NULL; 1011 sentinel.ai_next = NULL; 1012 cur = &sentinel; 1013 1014 /* 1015 * filter out AFs that are not supported by the kernel 1016 * XXX errno? 1017 */ 1018 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1019 if (s < 0) { 1020 if (errno != EMFILE) 1021 return 0; 1022 } else 1023 _close(s); 1024 1025 /* 1026 * if the servname does not match socktype/protocol, ignore it. 1027 */ 1028 if (get_portmatch(pai, servname) != 0) 1029 return 0; 1030 1031 afd = find_afd(pai->ai_family); 1032 if (afd == NULL) 1033 return 0; 1034 1035 if (pai->ai_flags & AI_PASSIVE) { 1036 GET_AI(cur->ai_next, afd, afd->a_addrany); 1037 /* xxx meaningless? 1038 * GET_CANONNAME(cur->ai_next, "anyaddr"); 1039 */ 1040 GET_PORT(cur->ai_next, servname); 1041 } else { 1042 GET_AI(cur->ai_next, afd, afd->a_loopback); 1043 /* xxx meaningless? 1044 * GET_CANONNAME(cur->ai_next, "localhost"); 1045 */ 1046 GET_PORT(cur->ai_next, servname); 1047 } 1048 cur = cur->ai_next; 1049 1050 *res = sentinel.ai_next; 1051 return 0; 1052 1053free: 1054 if (sentinel.ai_next) 1055 freeaddrinfo(sentinel.ai_next); 1056 return error; 1057} 1058 1059/* 1060 * numeric hostname 1061 */ 1062static int 1063explore_numeric(pai, hostname, servname, res) 1064 const struct addrinfo *pai; 1065 const char *hostname; 1066 const char *servname; 1067 struct addrinfo **res; 1068{ 1069 const struct afd *afd; 1070 struct addrinfo *cur; 1071 struct addrinfo sentinel; 1072 int error; 1073 char pton[PTON_MAX]; 1074 1075 *res = NULL; 1076 sentinel.ai_next = NULL; 1077 cur = &sentinel; 1078 1079 /* 1080 * if the servname does not match socktype/protocol, ignore it. 1081 */ 1082 if (get_portmatch(pai, servname) != 0) 1083 return 0; 1084 1085 afd = find_afd(pai->ai_family); 1086 if (afd == NULL) 1087 return 0; 1088 1089 switch (afd->a_af) { 1090#if 1 /*X/Open spec*/ 1091 case AF_INET: 1092 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 1093 if (pai->ai_family == afd->a_af || 1094 pai->ai_family == PF_UNSPEC /*?*/) { 1095 GET_AI(cur->ai_next, afd, pton); 1096 GET_PORT(cur->ai_next, servname); 1097 while (cur && cur->ai_next) 1098 cur = cur->ai_next; 1099 } else 1100 ERR(EAI_FAMILY); /*xxx*/ 1101 } 1102 break; 1103#endif 1104 default: 1105 if (inet_pton(afd->a_af, hostname, pton) == 1) { 1106 if (pai->ai_family == afd->a_af || 1107 pai->ai_family == PF_UNSPEC /*?*/) { 1108 GET_AI(cur->ai_next, afd, pton); 1109 GET_PORT(cur->ai_next, servname); 1110 while (cur && cur->ai_next) 1111 cur = cur->ai_next; 1112 } else 1113 ERR(EAI_FAMILY); /* XXX */ 1114 } 1115 break; 1116 } 1117 1118 *res = sentinel.ai_next; 1119 return 0; 1120 1121free: 1122bad: 1123 if (sentinel.ai_next) 1124 freeaddrinfo(sentinel.ai_next); 1125 return error; 1126} 1127 1128/* 1129 * numeric hostname with scope 1130 */ 1131static int 1132explore_numeric_scope(pai, hostname, servname, res) 1133 const struct addrinfo *pai; 1134 const char *hostname; 1135 const char *servname; 1136 struct addrinfo **res; 1137{ 1138#if !defined(SCOPE_DELIMITER) || !defined(INET6) 1139 return explore_numeric(pai, hostname, servname, res); 1140#else 1141 const struct afd *afd; 1142 struct addrinfo *cur; 1143 int error; 1144 char *cp, *hostname2 = NULL, *scope, *addr; 1145 struct sockaddr_in6 *sin6; 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 if (!afd->a_scoped) 1158 return explore_numeric(pai, hostname, servname, res); 1159 1160 cp = strchr(hostname, SCOPE_DELIMITER); 1161 if (cp == NULL) 1162 return explore_numeric(pai, hostname, servname, res); 1163 1164 /* 1165 * Handle special case of <scoped_address><delimiter><scope id> 1166 */ 1167 hostname2 = strdup(hostname); 1168 if (hostname2 == NULL) 1169 return EAI_MEMORY; 1170 /* terminate at the delimiter */ 1171 hostname2[cp - hostname] = '\0'; 1172 addr = hostname2; 1173 scope = cp + 1; 1174 1175 error = explore_numeric(pai, addr, servname, res); 1176 if (error == 0) { 1177 u_int32_t scopeid; 1178 1179 for (cur = *res; cur; cur = cur->ai_next) { 1180 if (cur->ai_family != AF_INET6) 1181 continue; 1182 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1183 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1184 free(hostname2); 1185 return(EAI_NONAME); /* XXX: is return OK? */ 1186 } 1187 sin6->sin6_scope_id = scopeid; 1188 } 1189 } 1190 1191 free(hostname2); 1192 1193 return error; 1194#endif 1195} 1196 1197static int 1198get_canonname(pai, ai, str) 1199 const struct addrinfo *pai; 1200 struct addrinfo *ai; 1201 const char *str; 1202{ 1203 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1204 ai->ai_canonname = (char *)malloc(strlen(str) + 1); 1205 if (ai->ai_canonname == NULL) 1206 return EAI_MEMORY; 1207 strlcpy(ai->ai_canonname, str, strlen(str) + 1); 1208 } 1209 return 0; 1210} 1211 1212static struct addrinfo * 1213get_ai(pai, afd, addr) 1214 const struct addrinfo *pai; 1215 const struct afd *afd; 1216 const char *addr; 1217{ 1218 char *p; 1219 struct addrinfo *ai; 1220#ifdef FAITH 1221 struct in6_addr faith_prefix; 1222 char *fp_str; 1223 int translate = 0; 1224#endif 1225 1226#ifdef FAITH 1227 /* 1228 * Transfrom an IPv4 addr into a special IPv6 addr format for 1229 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1230 * 1231 * +-----------------------------------+------------+ 1232 * | faith prefix part (12 bytes) | embedded | 1233 * | | IPv4 addr part (4 bytes) 1234 * +-----------------------------------+------------+ 1235 * 1236 * faith prefix part is specified as ascii IPv6 addr format 1237 * in environmental variable GAI. 1238 * For FAITH to work correctly, routing to faith prefix must be 1239 * setup toward a machine where a FAITH daemon operates. 1240 * Also, the machine must enable some mechanizm 1241 * (e.g. faith interface hack) to divert those packet with 1242 * faith prefixed destination addr to user-land FAITH daemon. 1243 */ 1244 fp_str = getenv("GAI"); 1245 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1246 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1247 u_int32_t v4a; 1248 u_int8_t v4a_top; 1249 1250 memcpy(&v4a, addr, sizeof v4a); 1251 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1252 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1253 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1254 afd = &afdl[N_INET6]; 1255 memcpy(&faith_prefix.s6_addr[12], addr, 1256 sizeof(struct in_addr)); 1257 translate = 1; 1258 } 1259 } 1260#endif 1261 1262 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1263 + (afd->a_socklen)); 1264 if (ai == NULL) 1265 return NULL; 1266 1267 memcpy(ai, pai, sizeof(struct addrinfo)); 1268 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1269 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1270 ai->ai_addr->sa_len = afd->a_socklen; 1271 ai->ai_addrlen = afd->a_socklen; 1272 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1273 p = (char *)(void *)(ai->ai_addr); 1274#ifdef FAITH 1275 if (translate == 1) 1276 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1277 else 1278#endif 1279 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1280 return ai; 1281} 1282 1283static int 1284get_portmatch(ai, servname) 1285 const struct addrinfo *ai; 1286 const char *servname; 1287{ 1288 1289 /* get_port does not touch first argument. when matchonly == 1. */ 1290 /* LINTED const cast */ 1291 return get_port((struct addrinfo *)ai, servname, 1); 1292} 1293 1294static int 1295get_port(ai, servname, matchonly) 1296 struct addrinfo *ai; 1297 const char *servname; 1298 int matchonly; 1299{ 1300 const char *proto; 1301 struct servent *sp; 1302 int port; 1303 int allownumeric; 1304 1305 if (servname == NULL) 1306 return 0; 1307 switch (ai->ai_family) { 1308 case AF_INET: 1309#ifdef AF_INET6 1310 case AF_INET6: 1311#endif 1312 break; 1313 default: 1314 return 0; 1315 } 1316 1317 switch (ai->ai_socktype) { 1318 case SOCK_RAW: 1319 return EAI_SERVICE; 1320 case SOCK_DGRAM: 1321 case SOCK_STREAM: 1322 allownumeric = 1; 1323 break; 1324 case ANY: 1325 allownumeric = 0; 1326 break; 1327 default: 1328 return EAI_SOCKTYPE; 1329 } 1330 1331 if (str_isnumber(servname)) { 1332 if (!allownumeric) 1333 return EAI_SERVICE; 1334 port = atoi(servname); 1335 if (port < 0 || port > 65535) 1336 return EAI_SERVICE; 1337 port = htons(port); 1338 } else { 1339 switch (ai->ai_socktype) { 1340 case SOCK_DGRAM: 1341 proto = "udp"; 1342 break; 1343 case SOCK_STREAM: 1344 proto = "tcp"; 1345 break; 1346 default: 1347 proto = NULL; 1348 break; 1349 } 1350 1351 if ((sp = getservbyname(servname, proto)) == NULL) 1352 return EAI_SERVICE; 1353 port = sp->s_port; 1354 } 1355 1356 if (!matchonly) { 1357 switch (ai->ai_family) { 1358 case AF_INET: 1359 ((struct sockaddr_in *)(void *) 1360 ai->ai_addr)->sin_port = port; 1361 break; 1362#ifdef INET6 1363 case AF_INET6: 1364 ((struct sockaddr_in6 *)(void *) 1365 ai->ai_addr)->sin6_port = port; 1366 break; 1367#endif 1368 } 1369 } 1370 1371 return 0; 1372} 1373 1374static const struct afd * 1375find_afd(af) 1376 int af; 1377{ 1378 const struct afd *afd; 1379 1380 if (af == PF_UNSPEC) 1381 return NULL; 1382 for (afd = afdl; afd->a_af; afd++) { 1383 if (afd->a_af == af) 1384 return afd; 1385 } 1386 return NULL; 1387} 1388 1389/* 1390 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1391 * will take care of it. 1392 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1393 * if the code is right or not. 1394 * 1395 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1396 * _dns_getaddrinfo. 1397 */ 1398static int 1399addrconfig(pai) 1400 struct addrinfo *pai; 1401{ 1402 int s, af; 1403 1404 /* 1405 * TODO: 1406 * Note that implementation dependent test for address 1407 * configuration should be done everytime called 1408 * (or apropriate interval), 1409 * because addresses will be dynamically assigned or deleted. 1410 */ 1411 af = pai->ai_family; 1412 if (af == AF_UNSPEC) { 1413 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1414 af = AF_INET; 1415 else { 1416 _close(s); 1417 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1418 af = AF_INET6; 1419 else 1420 _close(s); 1421 } 1422 } 1423 if (af != AF_UNSPEC) { 1424 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1425 return 0; 1426 _close(s); 1427 } 1428 pai->ai_family = af; 1429 return 1; 1430} 1431 1432#ifdef INET6 1433/* convert a string to a scope identifier. XXX: IPv6 specific */ 1434static int 1435ip6_str2scopeid(scope, sin6, scopeid) 1436 char *scope; 1437 struct sockaddr_in6 *sin6; 1438 u_int32_t *scopeid; 1439{ 1440 u_long lscopeid; 1441 struct in6_addr *a6; 1442 char *ep; 1443 1444 a6 = &sin6->sin6_addr; 1445 1446 /* empty scopeid portion is invalid */ 1447 if (*scope == '\0') 1448 return -1; 1449 1450 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1451 /* 1452 * We currently assume a one-to-one mapping between links 1453 * and interfaces, so we simply use interface indices for 1454 * like-local scopes. 1455 */ 1456 *scopeid = if_nametoindex(scope); 1457 if (*scopeid == 0) 1458 goto trynumeric; 1459 return 0; 1460 } 1461 1462 /* still unclear about literal, allow numeric only - placeholder */ 1463 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1464 goto trynumeric; 1465 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1466 goto trynumeric; 1467 else 1468 goto trynumeric; /* global */ 1469 1470 /* try to convert to a numeric id as a last resort */ 1471 trynumeric: 1472 errno = 0; 1473 lscopeid = strtoul(scope, &ep, 10); 1474 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1475 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1476 return 0; 1477 else 1478 return -1; 1479} 1480#endif 1481 1482/* 1483 * FQDN hostname, DNS lookup 1484 */ 1485static int 1486explore_fqdn(pai, hostname, servname, res) 1487 const struct addrinfo *pai; 1488 const char *hostname; 1489 const char *servname; 1490 struct addrinfo **res; 1491{ 1492 struct addrinfo *result; 1493 struct addrinfo *cur; 1494 int error = 0; 1495 static const ns_dtab dtab[] = { 1496 NS_FILES_CB(_files_getaddrinfo, NULL) 1497 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1498 NS_NIS_CB(_yp_getaddrinfo, NULL) 1499 { 0 } 1500 }; 1501 1502 result = NULL; 1503 1504 THREAD_LOCK(); 1505 1506 /* 1507 * if the servname does not match socktype/protocol, ignore it. 1508 */ 1509 if (get_portmatch(pai, servname) != 0) { 1510 THREAD_UNLOCK(); 1511 return 0; 1512 } 1513 1514 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1515 default_dns_files, hostname, pai)) { 1516 case NS_TRYAGAIN: 1517 error = EAI_AGAIN; 1518 goto free; 1519 case NS_UNAVAIL: 1520 error = EAI_FAIL; 1521 goto free; 1522 case NS_NOTFOUND: 1523 error = EAI_NONAME; 1524 goto free; 1525 case NS_SUCCESS: 1526 error = 0; 1527 for (cur = result; cur; cur = cur->ai_next) { 1528 GET_PORT(cur, servname); 1529 /* canonname should be filled already */ 1530 } 1531 break; 1532 } 1533 THREAD_UNLOCK(); 1534 1535 *res = result; 1536 1537 return 0; 1538 1539free: 1540 THREAD_UNLOCK(); 1541 if (result) 1542 freeaddrinfo(result); 1543 return error; 1544} 1545 1546#ifdef DEBUG 1547static const char AskedForGot[] = 1548 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1549#endif 1550static FILE *hostf = NULL; 1551 1552static struct addrinfo * 1553getanswer(answer, anslen, qname, qtype, pai) 1554 const querybuf *answer; 1555 int anslen; 1556 const char *qname; 1557 int qtype; 1558 const struct addrinfo *pai; 1559{ 1560 struct addrinfo sentinel, *cur; 1561 struct addrinfo ai; 1562 const struct afd *afd; 1563 char *canonname; 1564 const HEADER *hp; 1565 const u_char *cp; 1566 int n; 1567 const u_char *eom; 1568 char *bp, *ep; 1569 int type, class, ancount, qdcount; 1570 int haveanswer, had_error; 1571 char tbuf[MAXDNAME]; 1572 int (*name_ok)(const char *); 1573 char hostbuf[8*1024]; 1574 1575 memset(&sentinel, 0, sizeof(sentinel)); 1576 cur = &sentinel; 1577 1578 canonname = NULL; 1579 eom = answer->buf + anslen; 1580 switch (qtype) { 1581 case T_A: 1582 case T_AAAA: 1583 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1584 name_ok = res_hnok; 1585 break; 1586 default: 1587 return (NULL); /* XXX should be abort(); */ 1588 } 1589 /* 1590 * find first satisfactory answer 1591 */ 1592 hp = &answer->hdr; 1593 ancount = ntohs(hp->ancount); 1594 qdcount = ntohs(hp->qdcount); 1595 bp = hostbuf; 1596 ep = hostbuf + sizeof hostbuf; 1597 cp = answer->buf + HFIXEDSZ; 1598 if (qdcount != 1) { 1599 h_errno = NO_RECOVERY; 1600 return (NULL); 1601 } 1602 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1603 if ((n < 0) || !(*name_ok)(bp)) { 1604 h_errno = NO_RECOVERY; 1605 return (NULL); 1606 } 1607 cp += n + QFIXEDSZ; 1608 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1609 /* res_send() has already verified that the query name is the 1610 * same as the one we sent; this just gets the expanded name 1611 * (i.e., with the succeeding search-domain tacked on). 1612 */ 1613 n = strlen(bp) + 1; /* for the \0 */ 1614 if (n >= MAXHOSTNAMELEN) { 1615 h_errno = NO_RECOVERY; 1616 return (NULL); 1617 } 1618 canonname = bp; 1619 bp += n; 1620 /* The qname can be abbreviated, but h_name is now absolute. */ 1621 qname = canonname; 1622 } 1623 haveanswer = 0; 1624 had_error = 0; 1625 while (ancount-- > 0 && cp < eom && !had_error) { 1626 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1627 if ((n < 0) || !(*name_ok)(bp)) { 1628 had_error++; 1629 continue; 1630 } 1631 cp += n; /* name */ 1632 type = _getshort(cp); 1633 cp += INT16SZ; /* type */ 1634 class = _getshort(cp); 1635 cp += INT16SZ + INT32SZ; /* class, TTL */ 1636 n = _getshort(cp); 1637 cp += INT16SZ; /* len */ 1638 if (class != C_IN) { 1639 /* XXX - debug? syslog? */ 1640 cp += n; 1641 continue; /* XXX - had_error++ ? */ 1642 } 1643 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1644 type == T_CNAME) { 1645 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1646 if ((n < 0) || !(*name_ok)(tbuf)) { 1647 had_error++; 1648 continue; 1649 } 1650 cp += n; 1651 /* Get canonical name. */ 1652 n = strlen(tbuf) + 1; /* for the \0 */ 1653 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1654 had_error++; 1655 continue; 1656 } 1657 strlcpy(bp, tbuf, ep - bp); 1658 canonname = bp; 1659 bp += n; 1660 continue; 1661 } 1662 if (qtype == T_ANY) { 1663 if (!(type == T_A || type == T_AAAA)) { 1664 cp += n; 1665 continue; 1666 } 1667 } else if (type != qtype) { 1668#ifdef DEBUG 1669 if (type != T_KEY && type != T_SIG) 1670 syslog(LOG_NOTICE|LOG_AUTH, 1671 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1672 qname, p_class(C_IN), p_type(qtype), 1673 p_type(type)); 1674#endif 1675 cp += n; 1676 continue; /* XXX - had_error++ ? */ 1677 } 1678 switch (type) { 1679 case T_A: 1680 case T_AAAA: 1681 if (strcasecmp(canonname, bp) != 0) { 1682#ifdef DEBUG 1683 syslog(LOG_NOTICE|LOG_AUTH, 1684 AskedForGot, canonname, bp); 1685#endif 1686 cp += n; 1687 continue; /* XXX - had_error++ ? */ 1688 } 1689 if (type == T_A && n != INADDRSZ) { 1690 cp += n; 1691 continue; 1692 } 1693 if (type == T_AAAA && n != IN6ADDRSZ) { 1694 cp += n; 1695 continue; 1696 } 1697#ifdef FILTER_V4MAPPED 1698 if (type == T_AAAA) { 1699 struct in6_addr in6; 1700 memcpy(&in6, cp, sizeof(in6)); 1701 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1702 cp += n; 1703 continue; 1704 } 1705 } 1706#endif 1707 if (!haveanswer) { 1708 int nn; 1709 1710 canonname = bp; 1711 nn = strlen(bp) + 1; /* for the \0 */ 1712 bp += nn; 1713 } 1714 1715 /* don't overwrite pai */ 1716 ai = *pai; 1717 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1718 afd = find_afd(ai.ai_family); 1719 if (afd == NULL) { 1720 cp += n; 1721 continue; 1722 } 1723 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1724 if (cur->ai_next == NULL) 1725 had_error++; 1726 while (cur && cur->ai_next) 1727 cur = cur->ai_next; 1728 cp += n; 1729 break; 1730 default: 1731 abort(); 1732 } 1733 if (!had_error) 1734 haveanswer++; 1735 } 1736 if (haveanswer) { 1737#if defined(RESOLVSORT) 1738 /* 1739 * We support only IPv4 address for backward 1740 * compatibility against gethostbyname(3). 1741 */ 1742 if (_res.nsort && qtype == T_A) { 1743 if (addr4sort(&sentinel) < 0) { 1744 freeaddrinfo(sentinel.ai_next); 1745 h_errno = NO_RECOVERY; 1746 return NULL; 1747 } 1748 } 1749#endif /*RESOLVSORT*/ 1750 if (!canonname) 1751 (void)get_canonname(pai, sentinel.ai_next, qname); 1752 else 1753 (void)get_canonname(pai, sentinel.ai_next, canonname); 1754 h_errno = NETDB_SUCCESS; 1755 return sentinel.ai_next; 1756 } 1757 1758 h_errno = NO_RECOVERY; 1759 return NULL; 1760} 1761 1762#ifdef RESOLVSORT 1763struct addr_ptr { 1764 struct addrinfo *ai; 1765 int aval; 1766}; 1767 1768static int 1769addr4sort(struct addrinfo *sentinel) 1770{ 1771 struct addrinfo *ai; 1772 struct addr_ptr *addrs, addr; 1773 struct sockaddr_in *sin; 1774 int naddrs, i, j; 1775 int needsort = 0; 1776 1777 if (!sentinel) 1778 return -1; 1779 naddrs = 0; 1780 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1781 naddrs++; 1782 if (naddrs < 2) 1783 return 0; /* We don't need sorting. */ 1784 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1785 return -1; 1786 i = 0; 1787 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1788 sin = (struct sockaddr_in *)ai->ai_addr; 1789 for (j = 0; (unsigned)j < _res.nsort; j++) { 1790 if (_res.sort_list[j].addr.s_addr == 1791 (sin->sin_addr.s_addr & _res.sort_list[j].mask)) 1792 break; 1793 } 1794 addrs[i].ai = ai; 1795 addrs[i].aval = j; 1796 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1797 needsort = i; 1798 i++; 1799 } 1800 if (!needsort) { 1801 free(addrs); 1802 return 0; 1803 } 1804 1805 while (needsort < naddrs) { 1806 for (j = needsort - 1; j >= 0; j--) { 1807 if (addrs[j].aval > addrs[j+1].aval) { 1808 addr = addrs[j]; 1809 addrs[j] = addrs[j + 1]; 1810 addrs[j + 1] = addr; 1811 } else 1812 break; 1813 } 1814 needsort++; 1815 } 1816 1817 ai = sentinel; 1818 for (i = 0; i < naddrs; ++i) { 1819 ai->ai_next = addrs[i].ai; 1820 ai = ai->ai_next; 1821 } 1822 ai->ai_next = NULL; 1823 free(addrs); 1824 return 0; 1825} 1826#endif /*RESOLVSORT*/ 1827 1828/*ARGSUSED*/ 1829static int 1830_dns_getaddrinfo(rv, cb_data, ap) 1831 void *rv; 1832 void *cb_data; 1833 va_list ap; 1834{ 1835 struct addrinfo *ai; 1836 querybuf *buf, *buf2; 1837 const char *name; 1838 const struct addrinfo *pai; 1839 struct addrinfo sentinel, *cur; 1840 struct res_target q, q2; 1841 1842 name = va_arg(ap, char *); 1843 pai = va_arg(ap, const struct addrinfo *); 1844 1845 memset(&q, 0, sizeof(q2)); 1846 memset(&q2, 0, sizeof(q2)); 1847 memset(&sentinel, 0, sizeof(sentinel)); 1848 cur = &sentinel; 1849 1850 buf = malloc(sizeof(*buf)); 1851 if (!buf) { 1852 h_errno = NETDB_INTERNAL; 1853 return NS_NOTFOUND; 1854 } 1855 buf2 = malloc(sizeof(*buf2)); 1856 if (!buf2) { 1857 free(buf); 1858 h_errno = NETDB_INTERNAL; 1859 return NS_NOTFOUND; 1860 } 1861 1862 switch (pai->ai_family) { 1863 case AF_UNSPEC: 1864 /* prefer IPv6 */ 1865 q.name = name; 1866 q.qclass = C_IN; 1867 q.qtype = T_AAAA; 1868 q.answer = buf->buf; 1869 q.anslen = sizeof(buf->buf); 1870 q.next = &q2; 1871 q2.name = name; 1872 q2.qclass = C_IN; 1873 q2.qtype = T_A; 1874 q2.answer = buf2->buf; 1875 q2.anslen = sizeof(buf2->buf); 1876 break; 1877 case AF_INET: 1878 q.name = name; 1879 q.qclass = C_IN; 1880 q.qtype = T_A; 1881 q.answer = buf->buf; 1882 q.anslen = sizeof(buf->buf); 1883 break; 1884 case AF_INET6: 1885 q.name = name; 1886 q.qclass = C_IN; 1887 q.qtype = T_AAAA; 1888 q.answer = buf->buf; 1889 q.anslen = sizeof(buf->buf); 1890 break; 1891 default: 1892 free(buf); 1893 free(buf2); 1894 return NS_UNAVAIL; 1895 } 1896 if (res_searchN(name, &q) < 0) { 1897 free(buf); 1898 free(buf2); 1899 return NS_NOTFOUND; 1900 } 1901 ai = getanswer(buf, q.n, q.name, q.qtype, pai); 1902 if (ai) { 1903 cur->ai_next = ai; 1904 while (cur && cur->ai_next) 1905 cur = cur->ai_next; 1906 } 1907 if (q.next) { 1908 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai); 1909 if (ai) 1910 cur->ai_next = ai; 1911 } 1912 free(buf); 1913 free(buf2); 1914 if (sentinel.ai_next == NULL) 1915 switch (h_errno) { 1916 case HOST_NOT_FOUND: 1917 return NS_NOTFOUND; 1918 case TRY_AGAIN: 1919 return NS_TRYAGAIN; 1920 default: 1921 return NS_UNAVAIL; 1922 } 1923 *((struct addrinfo **)rv) = sentinel.ai_next; 1924 return NS_SUCCESS; 1925} 1926 1927static void 1928_sethtent() 1929{ 1930 if (!hostf) 1931 hostf = fopen(_PATH_HOSTS, "r" ); 1932 else 1933 rewind(hostf); 1934} 1935 1936static void 1937_endhtent() 1938{ 1939 if (hostf) { 1940 (void) fclose(hostf); 1941 hostf = NULL; 1942 } 1943} 1944 1945static struct addrinfo * 1946_gethtent(name, pai) 1947 const char *name; 1948 const struct addrinfo *pai; 1949{ 1950 char *p; 1951 char *cp, *tname, *cname; 1952 struct addrinfo hints, *res0, *res; 1953 int error; 1954 const char *addr; 1955 char hostbuf[8*1024]; 1956 1957 if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) 1958 return (NULL); 1959again: 1960 if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) 1961 return (NULL); 1962 if (*p == '#') 1963 goto again; 1964 if (!(cp = strpbrk(p, "#\n"))) 1965 goto again; 1966 *cp = '\0'; 1967 if (!(cp = strpbrk(p, " \t"))) 1968 goto again; 1969 *cp++ = '\0'; 1970 addr = p; 1971 cname = NULL; 1972 /* if this is not something we're looking for, skip it. */ 1973 while (cp && *cp) { 1974 if (*cp == ' ' || *cp == '\t') { 1975 cp++; 1976 continue; 1977 } 1978 tname = cp; 1979 if (cname == NULL) 1980 cname = cp; 1981 if ((cp = strpbrk(cp, " \t")) != NULL) 1982 *cp++ = '\0'; 1983 if (strcasecmp(name, tname) == 0) 1984 goto found; 1985 } 1986 goto again; 1987 1988found: 1989 /* we should not glob socktype/protocol here */ 1990 memset(&hints, 0, sizeof(hints)); 1991 hints.ai_family = pai->ai_family; 1992 hints.ai_socktype = SOCK_DGRAM; 1993 hints.ai_protocol = 0; 1994 hints.ai_flags = AI_NUMERICHOST; 1995 error = getaddrinfo(addr, "0", &hints, &res0); 1996 if (error) 1997 goto again; 1998#ifdef FILTER_V4MAPPED 1999 /* XXX should check all items in the chain */ 2000 if (res0->ai_family == AF_INET6 && 2001 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2002 freeaddrinfo(res0); 2003 goto again; 2004 } 2005#endif 2006 for (res = res0; res; res = res->ai_next) { 2007 /* cover it up */ 2008 res->ai_flags = pai->ai_flags; 2009 res->ai_socktype = pai->ai_socktype; 2010 res->ai_protocol = pai->ai_protocol; 2011 2012 if (pai->ai_flags & AI_CANONNAME) { 2013 if (get_canonname(pai, res, cname) != 0) { 2014 freeaddrinfo(res0); 2015 goto again; 2016 } 2017 } 2018 } 2019 return res0; 2020} 2021 2022/*ARGSUSED*/ 2023static int 2024_files_getaddrinfo(rv, cb_data, ap) 2025 void *rv; 2026 void *cb_data; 2027 va_list ap; 2028{ 2029 const char *name; 2030 const struct addrinfo *pai; 2031 struct addrinfo sentinel, *cur; 2032 struct addrinfo *p; 2033 2034 name = va_arg(ap, char *); 2035 pai = va_arg(ap, struct addrinfo *); 2036 2037 memset(&sentinel, 0, sizeof(sentinel)); 2038 cur = &sentinel; 2039 2040 _sethtent(); 2041 while ((p = _gethtent(name, pai)) != NULL) { 2042 cur->ai_next = p; 2043 while (cur && cur->ai_next) 2044 cur = cur->ai_next; 2045 } 2046 _endhtent(); 2047 2048 *((struct addrinfo **)rv) = sentinel.ai_next; 2049 if (sentinel.ai_next == NULL) 2050 return NS_NOTFOUND; 2051 return NS_SUCCESS; 2052} 2053 2054#ifdef YP 2055static char *__ypdomain; 2056 2057/*ARGSUSED*/ 2058static struct addrinfo * 2059_yphostent(line, pai) 2060 char *line; 2061 const struct addrinfo *pai; 2062{ 2063 struct addrinfo sentinel, *cur; 2064 struct addrinfo hints, *res, *res0; 2065 int error; 2066 char *p = line; 2067 const char *addr, *canonname; 2068 char *nextline; 2069 char *cp; 2070 2071 addr = canonname = NULL; 2072 2073 memset(&sentinel, 0, sizeof(sentinel)); 2074 cur = &sentinel; 2075 2076nextline: 2077 /* terminate line */ 2078 cp = strchr(p, '\n'); 2079 if (cp) { 2080 *cp++ = '\0'; 2081 nextline = cp; 2082 } else 2083 nextline = NULL; 2084 2085 cp = strpbrk(p, " \t"); 2086 if (cp == NULL) { 2087 if (canonname == NULL) 2088 return (NULL); 2089 else 2090 goto done; 2091 } 2092 *cp++ = '\0'; 2093 2094 addr = p; 2095 2096 while (cp && *cp) { 2097 if (*cp == ' ' || *cp == '\t') { 2098 cp++; 2099 continue; 2100 } 2101 if (!canonname) 2102 canonname = cp; 2103 if ((cp = strpbrk(cp, " \t")) != NULL) 2104 *cp++ = '\0'; 2105 } 2106 2107 hints = *pai; 2108 hints.ai_flags = AI_NUMERICHOST; 2109 error = getaddrinfo(addr, NULL, &hints, &res0); 2110 if (error == 0) { 2111 for (res = res0; res; res = res->ai_next) { 2112 /* cover it up */ 2113 res->ai_flags = pai->ai_flags; 2114 2115 if (pai->ai_flags & AI_CANONNAME) 2116 (void)get_canonname(pai, res, canonname); 2117 } 2118 } else 2119 res0 = NULL; 2120 if (res0) { 2121 cur->ai_next = res0; 2122 while (cur && cur->ai_next) 2123 cur = cur->ai_next; 2124 } 2125 2126 if (nextline) { 2127 p = nextline; 2128 goto nextline; 2129 } 2130 2131done: 2132 return sentinel.ai_next; 2133} 2134 2135/*ARGSUSED*/ 2136static int 2137_yp_getaddrinfo(rv, cb_data, ap) 2138 void *rv; 2139 void *cb_data; 2140 va_list ap; 2141{ 2142 struct addrinfo sentinel, *cur; 2143 struct addrinfo *ai = NULL; 2144 static char *__ypcurrent; 2145 int __ypcurrentlen, r; 2146 const char *name; 2147 const struct addrinfo *pai; 2148 2149 name = va_arg(ap, char *); 2150 pai = va_arg(ap, const struct addrinfo *); 2151 2152 memset(&sentinel, 0, sizeof(sentinel)); 2153 cur = &sentinel; 2154 2155 if (!__ypdomain) { 2156 if (_yp_check(&__ypdomain) == 0) 2157 return NS_UNAVAIL; 2158 } 2159 if (__ypcurrent) 2160 free(__ypcurrent); 2161 __ypcurrent = NULL; 2162 2163 /* hosts.byname is only for IPv4 (Solaris8) */ 2164 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2165 r = yp_match(__ypdomain, "hosts.byname", name, 2166 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 2167 if (r == 0) { 2168 struct addrinfo ai4; 2169 2170 ai4 = *pai; 2171 ai4.ai_family = AF_INET; 2172 ai = _yphostent(__ypcurrent, &ai4); 2173 if (ai) { 2174 cur->ai_next = ai; 2175 while (cur && cur->ai_next) 2176 cur = cur->ai_next; 2177 } 2178 } 2179 } 2180 2181 /* ipnodes.byname can hold both IPv4/v6 */ 2182 r = yp_match(__ypdomain, "ipnodes.byname", name, 2183 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 2184 if (r == 0) { 2185 ai = _yphostent(__ypcurrent, pai); 2186 if (ai) { 2187 cur->ai_next = ai; 2188 while (cur && cur->ai_next) 2189 cur = cur->ai_next; 2190 } 2191 } 2192 2193 if (sentinel.ai_next == NULL) { 2194 h_errno = HOST_NOT_FOUND; 2195 return NS_NOTFOUND; 2196 } 2197 *((struct addrinfo **)rv) = sentinel.ai_next; 2198 return NS_SUCCESS; 2199} 2200#endif 2201 2202/* resolver logic */ 2203 2204extern const char *__hostalias(const char *); 2205extern int h_errno; 2206 2207/* 2208 * Formulate a normal query, send, and await answer. 2209 * Returned answer is placed in supplied buffer "answer". 2210 * Perform preliminary check of answer, returning success only 2211 * if no error is indicated and the answer count is nonzero. 2212 * Return the size of the response on success, -1 on error. 2213 * Error number is left in h_errno. 2214 * 2215 * Caller must parse answer and determine whether it answers the question. 2216 */ 2217static int 2218res_queryN(name, target) 2219 const char *name; /* domain name */ 2220 struct res_target *target; 2221{ 2222 u_char *buf; 2223 HEADER *hp; 2224 int n; 2225 struct res_target *t; 2226 int rcode; 2227 int ancount; 2228 2229 rcode = NOERROR; 2230 ancount = 0; 2231 2232 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2233 h_errno = NETDB_INTERNAL; 2234 return (-1); 2235 } 2236 2237 buf = malloc(MAXPACKET); 2238 if (!buf) { 2239 h_errno = NETDB_INTERNAL; 2240 return -1; 2241 } 2242 2243 for (t = target; t; t = t->next) { 2244 int class, type; 2245 u_char *answer; 2246 int anslen; 2247 2248 hp = (HEADER *)(void *)t->answer; 2249 hp->rcode = NOERROR; /* default */ 2250 2251 /* make it easier... */ 2252 class = t->qclass; 2253 type = t->qtype; 2254 answer = t->answer; 2255 anslen = t->anslen; 2256#ifdef DEBUG 2257 if (_res.options & RES_DEBUG) 2258 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2259#endif 2260 2261 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, 2262 buf, MAXPACKET); 2263 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) 2264 n = res_opt(n, buf, MAXPACKET, anslen); 2265 if (n <= 0) { 2266#ifdef DEBUG 2267 if (_res.options & RES_DEBUG) 2268 printf(";; res_query: mkquery failed\n"); 2269#endif 2270 free(buf); 2271 h_errno = NO_RECOVERY; 2272 return (n); 2273 } 2274 n = res_send(buf, n, answer, anslen); 2275#if 0 2276 if (n < 0) { 2277#ifdef DEBUG 2278 if (_res.options & RES_DEBUG) 2279 printf(";; res_query: send error\n"); 2280#endif 2281 free(buf); 2282 h_errno = TRY_AGAIN; 2283 return (n); 2284 } 2285#endif 2286 2287 if (n < 0 || n > anslen) 2288 hp->rcode = FORMERR; /* XXX not very informative */ 2289 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2290 rcode = hp->rcode; /* record most recent error */ 2291#ifdef DEBUG 2292 if (_res.options & RES_DEBUG) 2293 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2294 ntohs(hp->ancount)); 2295#endif 2296 continue; 2297 } 2298 2299 ancount += ntohs(hp->ancount); 2300 2301 t->n = n; 2302 } 2303 2304 free(buf); 2305 2306 if (ancount == 0) { 2307 switch (rcode) { 2308 case NXDOMAIN: 2309 h_errno = HOST_NOT_FOUND; 2310 break; 2311 case SERVFAIL: 2312 h_errno = TRY_AGAIN; 2313 break; 2314 case NOERROR: 2315 h_errno = NO_DATA; 2316 break; 2317 case FORMERR: 2318 case NOTIMP: 2319 case REFUSED: 2320 default: 2321 h_errno = NO_RECOVERY; 2322 break; 2323 } 2324 return (-1); 2325 } 2326 return (ancount); 2327} 2328 2329/* 2330 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2331 * Return the size of the response on success, -1 on error. 2332 * If enabled, implement search rules until answer or unrecoverable failure 2333 * is detected. Error code, if any, is left in h_errno. 2334 */ 2335static int 2336res_searchN(name, target) 2337 const char *name; /* domain name */ 2338 struct res_target *target; 2339{ 2340 const char *cp, * const *domain; 2341 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2342 u_int dots; 2343 int trailing_dot, ret, saved_herrno; 2344 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 2345 2346 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2347 h_errno = NETDB_INTERNAL; 2348 return (-1); 2349 } 2350 2351 errno = 0; 2352 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 2353 dots = 0; 2354 for (cp = name; *cp; cp++) 2355 dots += (*cp == '.'); 2356 trailing_dot = 0; 2357 if (cp > name && *--cp == '.') 2358 trailing_dot++; 2359 2360 /* 2361 * if there aren't any dots, it could be a user-level alias 2362 */ 2363 if (!dots && (cp = __hostalias(name)) != NULL) 2364 return (res_queryN(cp, target)); 2365 2366 /* 2367 * If there are dots in the name already, let's just give it a try 2368 * 'as is'. The threshold can be set with the "ndots" option. 2369 */ 2370 saved_herrno = -1; 2371 if (dots >= _res.ndots) { 2372 ret = res_querydomainN(name, NULL, target); 2373 if (ret > 0) 2374 return (ret); 2375 saved_herrno = h_errno; 2376 tried_as_is++; 2377 } 2378 2379 /* 2380 * We do at least one level of search if 2381 * - there is no dot and RES_DEFNAME is set, or 2382 * - there is at least one dot, there is no trailing dot, 2383 * and RES_DNSRCH is set. 2384 */ 2385 if ((!dots && (_res.options & RES_DEFNAMES)) || 2386 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { 2387 int done = 0; 2388 2389 for (domain = (const char * const *)_res.dnsrch; 2390 *domain && !done; 2391 domain++) { 2392 2393 ret = res_querydomainN(name, *domain, target); 2394 if (ret > 0) 2395 return (ret); 2396 2397 /* 2398 * If no server present, give up. 2399 * If name isn't found in this domain, 2400 * keep trying higher domains in the search list 2401 * (if that's enabled). 2402 * On a NO_DATA error, keep trying, otherwise 2403 * a wildcard entry of another type could keep us 2404 * from finding this entry higher in the domain. 2405 * If we get some other error (negative answer or 2406 * server failure), then stop searching up, 2407 * but try the input name below in case it's 2408 * fully-qualified. 2409 */ 2410 if (errno == ECONNREFUSED) { 2411 h_errno = TRY_AGAIN; 2412 return (-1); 2413 } 2414 2415 switch (h_errno) { 2416 case NO_DATA: 2417 got_nodata++; 2418 /* FALLTHROUGH */ 2419 case HOST_NOT_FOUND: 2420 /* keep trying */ 2421 break; 2422 case TRY_AGAIN: 2423 if (hp->rcode == SERVFAIL) { 2424 /* try next search element, if any */ 2425 got_servfail++; 2426 break; 2427 } 2428 /* FALLTHROUGH */ 2429 default: 2430 /* anything else implies that we're done */ 2431 done++; 2432 } 2433 /* 2434 * if we got here for some reason other than DNSRCH, 2435 * we only wanted one iteration of the loop, so stop. 2436 */ 2437 if (!(_res.options & RES_DNSRCH)) 2438 done++; 2439 } 2440 } 2441 2442 /* 2443 * if we have not already tried the name "as is", do that now. 2444 * note that we do this regardless of how many dots were in the 2445 * name or whether it ends with a dot. 2446 */ 2447 if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) { 2448 ret = res_querydomainN(name, NULL, target); 2449 if (ret > 0) 2450 return (ret); 2451 } 2452 2453 /* 2454 * if we got here, we didn't satisfy the search. 2455 * if we did an initial full query, return that query's h_errno 2456 * (note that we wouldn't be here if that query had succeeded). 2457 * else if we ever got a nodata, send that back as the reason. 2458 * else send back meaningless h_errno, that being the one from 2459 * the last DNSRCH we did. 2460 */ 2461 if (saved_herrno != -1) 2462 h_errno = saved_herrno; 2463 else if (got_nodata) 2464 h_errno = NO_DATA; 2465 else if (got_servfail) 2466 h_errno = TRY_AGAIN; 2467 return (-1); 2468} 2469 2470/* 2471 * Perform a call on res_query on the concatenation of name and domain, 2472 * removing a trailing dot from name if domain is NULL. 2473 */ 2474static int 2475res_querydomainN(name, domain, target) 2476 const char *name, *domain; 2477 struct res_target *target; 2478{ 2479 char nbuf[MAXDNAME]; 2480 const char *longname = nbuf; 2481 size_t n, d; 2482 2483 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2484 h_errno = NETDB_INTERNAL; 2485 return (-1); 2486 } 2487#ifdef DEBUG 2488 if (_res.options & RES_DEBUG) 2489 printf(";; res_querydomain(%s, %s)\n", 2490 name, domain?domain:"<Nil>"); 2491#endif 2492 if (domain == NULL) { 2493 /* 2494 * Check for trailing '.'; 2495 * copy without '.' if present. 2496 */ 2497 n = strlen(name); 2498 if (n >= MAXDNAME) { 2499 h_errno = NO_RECOVERY; 2500 return (-1); 2501 } 2502 if (n > 0 && name[--n] == '.') { 2503 strncpy(nbuf, name, n); 2504 nbuf[n] = '\0'; 2505 } else 2506 longname = name; 2507 } else { 2508 n = strlen(name); 2509 d = strlen(domain); 2510 if (n + d + 1 >= MAXDNAME) { 2511 h_errno = NO_RECOVERY; 2512 return (-1); 2513 } 2514 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2515 } 2516 return (res_queryN(longname, target)); 2517} 2518