getaddrinfo.c revision 144634
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 144634 2005-04-04 19:45:27Z ume $"); 67 68#include "namespace.h" 69#include <sys/types.h> 70#include <sys/param.h> 71#include <sys/socket.h> 72#include <net/if.h> 73#include <netinet/in.h> 74#include <sys/queue.h> 75#ifdef INET6 76#include <net/if_var.h> 77#include <sys/sysctl.h> 78#include <sys/ioctl.h> 79#include <netinet6/in6_var.h> /* XXX */ 80#endif 81#include <arpa/inet.h> 82#include <arpa/nameser.h> 83#include <rpc/rpc.h> 84#include <rpcsvc/yp_prot.h> 85#include <rpcsvc/ypclnt.h> 86#include <netdb.h> 87#include <pthread.h> 88#include <resolv.h> 89#include <string.h> 90#include <stdlib.h> 91#include <stddef.h> 92#include <ctype.h> 93#include <unistd.h> 94#include <stdio.h> 95#include <errno.h> 96 97#include "res_config.h" 98 99#ifdef DEBUG 100#include <syslog.h> 101#endif 102 103#include <stdarg.h> 104#include <nsswitch.h> 105#include "un-namespace.h" 106#include "libc_private.h" 107 108#if defined(__KAME__) && defined(INET6) 109# define FAITH 110#endif 111 112#define SUCCESS 0 113#define ANY 0 114#define YES 1 115#define NO 0 116 117static const char in_addrany[] = { 0, 0, 0, 0 }; 118static const char in_loopback[] = { 127, 0, 0, 1 }; 119#ifdef INET6 120static const char in6_addrany[] = { 121 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 122}; 123static const char in6_loopback[] = { 124 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 125}; 126#endif 127 128struct policyqueue { 129 TAILQ_ENTRY(policyqueue) pc_entry; 130#ifdef INET6 131 struct in6_addrpolicy pc_policy; 132#endif 133}; 134TAILQ_HEAD(policyhead, policyqueue); 135 136static const struct afd { 137 int a_af; 138 int a_addrlen; 139 int a_socklen; 140 int a_off; 141 const char *a_addrany; 142 const char *a_loopback; 143 int a_scoped; 144} afdl [] = { 145#ifdef INET6 146#define N_INET6 0 147 {PF_INET6, sizeof(struct in6_addr), 148 sizeof(struct sockaddr_in6), 149 offsetof(struct sockaddr_in6, sin6_addr), 150 in6_addrany, in6_loopback, 1}, 151#define N_INET 1 152#else 153#define N_INET 0 154#endif 155 {PF_INET, sizeof(struct in_addr), 156 sizeof(struct sockaddr_in), 157 offsetof(struct sockaddr_in, sin_addr), 158 in_addrany, in_loopback, 0}, 159 {0, 0, 0, 0, NULL, NULL, 0}, 160}; 161 162struct explore { 163 int e_af; 164 int e_socktype; 165 int e_protocol; 166 const char *e_protostr; 167 int e_wild; 168#define WILD_AF(ex) ((ex)->e_wild & 0x01) 169#define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 170#define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 171}; 172 173static const struct explore explore[] = { 174#if 0 175 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 176#endif 177#ifdef INET6 178 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 179 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 180 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 181#endif 182 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 183 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 184 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 185 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 186 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 187 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, 188 { -1, 0, 0, NULL, 0 }, 189}; 190 191#ifdef INET6 192#define PTON_MAX 16 193#else 194#define PTON_MAX 4 195#endif 196 197#define AIO_SRCFLAG_DEPRECATED 0x1 198 199struct ai_order { 200 union { 201 struct sockaddr_storage aiou_ss; 202 struct sockaddr aiou_sa; 203 } aio_src_un; 204#define aio_srcsa aio_src_un.aiou_sa 205 u_int32_t aio_srcflag; 206 int aio_srcscope; 207 int aio_dstscope; 208 struct policyqueue *aio_srcpolicy; 209 struct policyqueue *aio_dstpolicy; 210 struct addrinfo *aio_ai; 211 int aio_matchlen; 212}; 213 214static const ns_src default_dns_files[] = { 215 { NSSRC_FILES, NS_SUCCESS }, 216 { NSSRC_DNS, NS_SUCCESS }, 217 { 0 } 218}; 219 220struct res_target { 221 struct res_target *next; 222 const char *name; /* domain name */ 223 int qclass, qtype; /* class and type of query */ 224 u_char *answer; /* buffer to put answer */ 225 int anslen; /* size of answer buffer */ 226 int n; /* result length */ 227}; 228 229#define MAXPACKET (64*1024) 230 231typedef union { 232 HEADER hdr; 233 u_char buf[MAXPACKET]; 234} querybuf; 235 236static int str2number(const char *); 237static int explore_null(const struct addrinfo *, 238 const char *, struct addrinfo **); 239static int explore_numeric(const struct addrinfo *, const char *, 240 const char *, struct addrinfo **, const char *); 241static int explore_numeric_scope(const struct addrinfo *, const char *, 242 const char *, struct addrinfo **); 243static int get_canonname(const struct addrinfo *, 244 struct addrinfo *, const char *); 245static struct addrinfo *get_ai(const struct addrinfo *, 246 const struct afd *, const char *); 247static int get_portmatch(const struct addrinfo *, const char *); 248static int get_port(struct addrinfo *, const char *, int); 249static const struct afd *find_afd(int); 250static int addrconfig(struct addrinfo *); 251static void set_source(struct ai_order *, struct policyhead *); 252static int comp_dst(const void *, const void *); 253#ifdef INET6 254static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 255#endif 256static int gai_addr2scopetype(struct sockaddr *); 257 258static int explore_fqdn(const struct addrinfo *, const char *, 259 const char *, struct addrinfo **); 260 261static int reorder(struct addrinfo *); 262static int get_addrselectpolicy(struct policyhead *); 263static void free_addrselectpolicy(struct policyhead *); 264static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 265 struct policyhead *); 266static int matchlen(struct sockaddr *, struct sockaddr *); 267 268static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 269 const struct addrinfo *); 270#if defined(RESOLVSORT) 271static int addr4sort(struct addrinfo *); 272#endif 273static int _dns_getaddrinfo(void *, void *, va_list); 274static void _sethtent(FILE **); 275static void _endhtent(FILE **); 276static struct addrinfo *_gethtent(FILE **, const char *, 277 const struct addrinfo *); 278static int _files_getaddrinfo(void *, void *, va_list); 279#ifdef YP 280static struct addrinfo *_yphostent(char *, const struct addrinfo *); 281static int _yp_getaddrinfo(void *, void *, va_list); 282#endif 283 284static int res_queryN(const char *, struct res_target *); 285static int res_searchN(const char *, struct res_target *); 286static int res_querydomainN(const char *, const char *, 287 struct res_target *); 288 289/* Entries EAI_ADDRFAMILY (1) and EAI_NODATA (7) are obsoleted, but left */ 290/* for backward compatibility with userland code prior to 2553bis-02 */ 291static const char *ai_errlist[] = { 292 "Success", /* 0 */ 293 "Address family for hostname not supported", /* 1 */ 294 "Temporary failure in name resolution", /* EAI_AGAIN */ 295 "Invalid value for ai_flags", /* EAI_BADFLAGS */ 296 "Non-recoverable failure in name resolution", /* EAI_FAIL */ 297 "ai_family not supported", /* EAI_FAMILY */ 298 "Memory allocation failure", /* EAI_MEMORY */ 299 "No address associated with hostname", /* 7 */ 300 "hostname nor servname provided, or not known", /* EAI_NONAME */ 301 "servname not supported for ai_socktype", /* EAI_SERVICE */ 302 "ai_socktype not supported", /* EAI_SOCKTYPE */ 303 "System error returned in errno", /* EAI_SYSTEM */ 304 "Invalid value for hints", /* EAI_BADHINTS */ 305 "Resolved protocol is unknown" /* EAI_PROTOCOL */ 306}; 307 308/* 309 * XXX: Many dependencies are not thread-safe. So, we share lock between 310 * getaddrinfo() and getipnodeby*(). Still, we cannot use 311 * getaddrinfo() and getipnodeby*() in conjunction with other 312 * functions which call them. 313 */ 314pthread_mutex_t __getaddrinfo_thread_lock = PTHREAD_MUTEX_INITIALIZER; 315#define THREAD_LOCK() \ 316 if (__isthreaded) _pthread_mutex_lock(&__getaddrinfo_thread_lock); 317#define THREAD_UNLOCK() \ 318 if (__isthreaded) _pthread_mutex_unlock(&__getaddrinfo_thread_lock); 319 320/* XXX macros that make external reference is BAD. */ 321 322#define GET_AI(ai, afd, addr) \ 323do { \ 324 /* external reference: pai, error, and label free */ \ 325 (ai) = get_ai(pai, (afd), (addr)); \ 326 if ((ai) == NULL) { \ 327 error = EAI_MEMORY; \ 328 goto free; \ 329 } \ 330} while (/*CONSTCOND*/0) 331 332#define GET_PORT(ai, serv) \ 333do { \ 334 /* external reference: error and label free */ \ 335 error = get_port((ai), (serv), 0); \ 336 if (error != 0) \ 337 goto free; \ 338} while (/*CONSTCOND*/0) 339 340#define GET_CANONNAME(ai, str) \ 341do { \ 342 /* external reference: pai, error and label free */ \ 343 error = get_canonname(pai, (ai), (str)); \ 344 if (error != 0) \ 345 goto free; \ 346} while (/*CONSTCOND*/0) 347 348#define ERR(err) \ 349do { \ 350 /* external reference: error, and label bad */ \ 351 error = (err); \ 352 goto bad; \ 353 /*NOTREACHED*/ \ 354} while (/*CONSTCOND*/0) 355 356#define MATCH_FAMILY(x, y, w) \ 357 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 358#define MATCH(x, y, w) \ 359 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 360 361const char * 362gai_strerror(int ecode) 363{ 364 if (ecode >= 0 && ecode < EAI_MAX) 365 return ai_errlist[ecode]; 366 return "Unknown error"; 367} 368 369void 370freeaddrinfo(ai) 371 struct addrinfo *ai; 372{ 373 struct addrinfo *next; 374 375 do { 376 next = ai->ai_next; 377 if (ai->ai_canonname) 378 free(ai->ai_canonname); 379 /* no need to free(ai->ai_addr) */ 380 free(ai); 381 ai = next; 382 } while (ai); 383} 384 385static int 386str2number(p) 387 const char *p; 388{ 389 char *ep; 390 unsigned long v; 391 392 if (*p == '\0') 393 return -1; 394 ep = NULL; 395 errno = 0; 396 v = strtoul(p, &ep, 10); 397 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) 398 return v; 399 else 400 return -1; 401} 402 403int 404getaddrinfo(hostname, servname, hints, res) 405 const char *hostname, *servname; 406 const struct addrinfo *hints; 407 struct addrinfo **res; 408{ 409 struct addrinfo sentinel; 410 struct addrinfo *cur; 411 int error = 0; 412 struct addrinfo ai; 413 struct addrinfo ai0; 414 struct addrinfo *pai; 415 const struct explore *ex; 416 int numeric = 0; 417 418 memset(&sentinel, 0, sizeof(sentinel)); 419 cur = &sentinel; 420 pai = &ai; 421 pai->ai_flags = 0; 422 pai->ai_family = PF_UNSPEC; 423 pai->ai_socktype = ANY; 424 pai->ai_protocol = ANY; 425 pai->ai_addrlen = 0; 426 pai->ai_canonname = NULL; 427 pai->ai_addr = NULL; 428 pai->ai_next = NULL; 429 430 if (hostname == NULL && servname == NULL) 431 return EAI_NONAME; 432 if (hints) { 433 /* error check for hints */ 434 if (hints->ai_addrlen || hints->ai_canonname || 435 hints->ai_addr || hints->ai_next) 436 ERR(EAI_BADHINTS); /* xxx */ 437 if (hints->ai_flags & ~AI_MASK) 438 ERR(EAI_BADFLAGS); 439 switch (hints->ai_family) { 440 case PF_UNSPEC: 441 case PF_INET: 442#ifdef INET6 443 case PF_INET6: 444#endif 445 break; 446 default: 447 ERR(EAI_FAMILY); 448 } 449 memcpy(pai, hints, sizeof(*pai)); 450 451 /* 452 * if both socktype/protocol are specified, check if they 453 * are meaningful combination. 454 */ 455 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 456 for (ex = explore; ex->e_af >= 0; ex++) { 457 if (pai->ai_family != ex->e_af) 458 continue; 459 if (ex->e_socktype == ANY) 460 continue; 461 if (ex->e_protocol == ANY) 462 continue; 463 if (pai->ai_socktype == ex->e_socktype && 464 pai->ai_protocol != ex->e_protocol) { 465 ERR(EAI_BADHINTS); 466 } 467 } 468 } 469 } 470 471 /* 472 * post-2553: AI_ALL and AI_V4MAPPED are effective only against 473 * AF_INET6 query. They need to be ignored if specified in other 474 * occassions. 475 */ 476 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 477 case AI_V4MAPPED: 478 case AI_ALL | AI_V4MAPPED: 479 if (pai->ai_family != AF_INET6) 480 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 481 break; 482 case AI_ALL: 483#if 1 484 /* illegal */ 485 ERR(EAI_BADFLAGS); 486#else 487 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 488#endif 489 break; 490 } 491 492 /* 493 * check for special cases. (1) numeric servname is disallowed if 494 * socktype/protocol are left unspecified. (2) servname is disallowed 495 * for raw and other inet{,6} sockets. 496 */ 497 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 498#ifdef PF_INET6 499 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 500#endif 501 ) { 502 ai0 = *pai; /* backup *pai */ 503 504 if (pai->ai_family == PF_UNSPEC) { 505#ifdef PF_INET6 506 pai->ai_family = PF_INET6; 507#else 508 pai->ai_family = PF_INET; 509#endif 510 } 511 error = get_portmatch(pai, servname); 512 if (error) 513 ERR(error); 514 515 *pai = ai0; 516 } 517 518 ai0 = *pai; 519 520 /* NULL hostname, or numeric hostname */ 521 for (ex = explore; ex->e_af >= 0; ex++) { 522 *pai = ai0; 523 524 /* PF_UNSPEC entries are prepared for DNS queries only */ 525 if (ex->e_af == PF_UNSPEC) 526 continue; 527 528 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 529 continue; 530 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 531 continue; 532 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 533 continue; 534 535 if (pai->ai_family == PF_UNSPEC) 536 pai->ai_family = ex->e_af; 537 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 538 pai->ai_socktype = ex->e_socktype; 539 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 540 pai->ai_protocol = ex->e_protocol; 541 542 if (hostname == NULL) 543 error = explore_null(pai, servname, &cur->ai_next); 544 else 545 error = explore_numeric_scope(pai, hostname, servname, 546 &cur->ai_next); 547 548 if (error) 549 goto free; 550 551 while (cur && cur->ai_next) 552 cur = cur->ai_next; 553 } 554 555 /* 556 * XXX 557 * If numreic representation of AF1 can be interpreted as FQDN 558 * representation of AF2, we need to think again about the code below. 559 */ 560 if (sentinel.ai_next) { 561 numeric = 1; 562 goto good; 563 } 564 565 if (hostname == NULL) 566 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 567 if (pai->ai_flags & AI_NUMERICHOST) 568 ERR(EAI_NONAME); 569 570 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 571 ERR(EAI_FAIL); 572 573 /* 574 * hostname as alphabetical name. 575 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 576 * outer loop by AFs. 577 */ 578 for (ex = explore; ex->e_af >= 0; ex++) { 579 *pai = ai0; 580 581 /* require exact match for family field */ 582 if (pai->ai_family != ex->e_af) 583 continue; 584 585 if (!MATCH(pai->ai_socktype, ex->e_socktype, 586 WILD_SOCKTYPE(ex))) { 587 continue; 588 } 589 if (!MATCH(pai->ai_protocol, ex->e_protocol, 590 WILD_PROTOCOL(ex))) { 591 continue; 592 } 593 594 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 595 pai->ai_socktype = ex->e_socktype; 596 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 597 pai->ai_protocol = ex->e_protocol; 598 599 error = explore_fqdn(pai, hostname, servname, 600 &cur->ai_next); 601 602 while (cur && cur->ai_next) 603 cur = cur->ai_next; 604 } 605 606 /* XXX inhibit errors if we have the result */ 607 if (sentinel.ai_next) 608 error = 0; 609 610good: 611 /* 612 * ensure we return either: 613 * - error == 0, non-NULL *res 614 * - error != 0, NULL *res 615 */ 616 if (error == 0) { 617 if (sentinel.ai_next) { 618 /* 619 * If the returned entry is for an active connection, 620 * and the given name is not numeric, reorder the 621 * list, so that the application would try the list 622 * in the most efficient order. 623 */ 624 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 625 if (!numeric) 626 (void)reorder(&sentinel); 627 } 628 *res = sentinel.ai_next; 629 return SUCCESS; 630 } else 631 error = EAI_FAIL; 632 } 633free: 634bad: 635 if (sentinel.ai_next) 636 freeaddrinfo(sentinel.ai_next); 637 *res = NULL; 638 return error; 639} 640 641static int 642reorder(sentinel) 643 struct addrinfo *sentinel; 644{ 645 struct addrinfo *ai, **aip; 646 struct ai_order *aio; 647 int i, n; 648 struct policyhead policyhead; 649 650 /* count the number of addrinfo elements for sorting. */ 651 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 652 ; 653 654 /* 655 * If the number is small enough, we can skip the reordering process. 656 */ 657 if (n <= 1) 658 return(n); 659 660 /* allocate a temporary array for sort and initialization of it. */ 661 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 662 return(n); /* give up reordering */ 663 memset(aio, 0, sizeof(*aio) * n); 664 665 /* retrieve address selection policy from the kernel */ 666 TAILQ_INIT(&policyhead); 667 if (!get_addrselectpolicy(&policyhead)) { 668 /* no policy is installed into kernel, we don't sort. */ 669 free(aio); 670 return (n); 671 } 672 673 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 674 aio[i].aio_ai = ai; 675 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 676 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 677 &policyhead); 678 set_source(&aio[i], &policyhead); 679 } 680 681 /* perform sorting. */ 682 qsort(aio, n, sizeof(*aio), comp_dst); 683 684 /* reorder the addrinfo chain. */ 685 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 686 *aip = aio[i].aio_ai; 687 aip = &aio[i].aio_ai->ai_next; 688 } 689 *aip = NULL; 690 691 /* cleanup and return */ 692 free(aio); 693 free_addrselectpolicy(&policyhead); 694 return(n); 695} 696 697static int 698get_addrselectpolicy(head) 699 struct policyhead *head; 700{ 701#ifdef INET6 702 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 703 size_t l; 704 char *buf; 705 struct in6_addrpolicy *pol, *ep; 706 707 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 708 return (0); 709 if ((buf = malloc(l)) == NULL) 710 return (0); 711 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 712 free(buf); 713 return (0); 714 } 715 716 ep = (struct in6_addrpolicy *)(buf + l); 717 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 718 struct policyqueue *new; 719 720 if ((new = malloc(sizeof(*new))) == NULL) { 721 free_addrselectpolicy(head); /* make the list empty */ 722 break; 723 } 724 new->pc_policy = *pol; 725 TAILQ_INSERT_TAIL(head, new, pc_entry); 726 } 727 728 free(buf); 729 return (1); 730#else 731 return (0); 732#endif 733} 734 735static void 736free_addrselectpolicy(head) 737 struct policyhead *head; 738{ 739 struct policyqueue *ent, *nent; 740 741 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 742 nent = TAILQ_NEXT(ent, pc_entry); 743 TAILQ_REMOVE(head, ent, pc_entry); 744 free(ent); 745 } 746} 747 748static struct policyqueue * 749match_addrselectpolicy(addr, head) 750 struct sockaddr *addr; 751 struct policyhead *head; 752{ 753#ifdef INET6 754 struct policyqueue *ent, *bestent = NULL; 755 struct in6_addrpolicy *pol; 756 int matchlen, bestmatchlen = -1; 757 u_char *mp, *ep, *k, *p, m; 758 struct sockaddr_in6 key; 759 760 switch(addr->sa_family) { 761 case AF_INET6: 762 key = *(struct sockaddr_in6 *)addr; 763 break; 764 case AF_INET: 765 /* convert the address into IPv4-mapped IPv6 address. */ 766 memset(&key, 0, sizeof(key)); 767 key.sin6_family = AF_INET6; 768 key.sin6_len = sizeof(key); 769 key.sin6_addr.s6_addr[10] = 0xff; 770 key.sin6_addr.s6_addr[11] = 0xff; 771 memcpy(&key.sin6_addr.s6_addr[12], 772 &((struct sockaddr_in *)addr)->sin_addr, 4); 773 break; 774 default: 775 return(NULL); 776 } 777 778 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 779 pol = &ent->pc_policy; 780 matchlen = 0; 781 782 mp = (u_char *)&pol->addrmask.sin6_addr; 783 ep = mp + 16; /* XXX: scope field? */ 784 k = (u_char *)&key.sin6_addr; 785 p = (u_char *)&pol->addr.sin6_addr; 786 for (; mp < ep && *mp; mp++, k++, p++) { 787 m = *mp; 788 if ((*k & m) != *p) 789 goto next; /* not match */ 790 if (m == 0xff) /* short cut for a typical case */ 791 matchlen += 8; 792 else { 793 while (m >= 0x80) { 794 matchlen++; 795 m <<= 1; 796 } 797 } 798 } 799 800 /* matched. check if this is better than the current best. */ 801 if (matchlen > bestmatchlen) { 802 bestent = ent; 803 bestmatchlen = matchlen; 804 } 805 806 next: 807 continue; 808 } 809 810 return(bestent); 811#else 812 return(NULL); 813#endif 814 815} 816 817static void 818set_source(aio, ph) 819 struct ai_order *aio; 820 struct policyhead *ph; 821{ 822 struct addrinfo ai = *aio->aio_ai; 823 struct sockaddr_storage ss; 824 int s, srclen; 825 826 /* set unspec ("no source is available"), just in case */ 827 aio->aio_srcsa.sa_family = AF_UNSPEC; 828 aio->aio_srcscope = -1; 829 830 switch(ai.ai_family) { 831 case AF_INET: 832#ifdef INET6 833 case AF_INET6: 834#endif 835 break; 836 default: /* ignore unsupported AFs explicitly */ 837 return; 838 } 839 840 /* XXX: make a dummy addrinfo to call connect() */ 841 ai.ai_socktype = SOCK_DGRAM; 842 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 843 ai.ai_next = NULL; 844 memset(&ss, 0, sizeof(ss)); 845 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 846 ai.ai_addr = (struct sockaddr *)&ss; 847 get_port(&ai, "1", 0); 848 849 /* open a socket to get the source address for the given dst */ 850 if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0) 851 return; /* give up */ 852 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 853 goto cleanup; 854 srclen = ai.ai_addrlen; 855 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 856 aio->aio_srcsa.sa_family = AF_UNSPEC; 857 goto cleanup; 858 } 859 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 860 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 861 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 862#ifdef INET6 863 if (ai.ai_family == AF_INET6) { 864 struct in6_ifreq ifr6; 865 u_int32_t flags6; 866 867 /* XXX: interface name should not be hardcoded */ 868 strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name)); 869 memset(&ifr6, 0, sizeof(ifr6)); 870 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 871 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 872 flags6 = ifr6.ifr_ifru.ifru_flags6; 873 if ((flags6 & IN6_IFF_DEPRECATED)) 874 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 875 } 876 } 877#endif 878 879 cleanup: 880 _close(s); 881 return; 882} 883 884static int 885matchlen(src, dst) 886 struct sockaddr *src, *dst; 887{ 888 int match = 0; 889 u_char *s, *d; 890 u_char *lim, r; 891 int addrlen; 892 893 switch (src->sa_family) { 894#ifdef INET6 895 case AF_INET6: 896 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 897 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 898 addrlen = sizeof(struct in6_addr); 899 lim = s + addrlen; 900 break; 901#endif 902 case AF_INET: 903 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 904 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 905 addrlen = sizeof(struct in_addr); 906 lim = s + addrlen; 907 break; 908 default: 909 return(0); 910 } 911 912 while (s < lim) 913 if ((r = (*d++ ^ *s++)) != 0) { 914 while (r < addrlen * 8) { 915 match++; 916 r <<= 1; 917 } 918 break; 919 } else 920 match += 8; 921 return(match); 922} 923 924static int 925comp_dst(arg1, arg2) 926 const void *arg1, *arg2; 927{ 928 const struct ai_order *dst1 = arg1, *dst2 = arg2; 929 930 /* 931 * Rule 1: Avoid unusable destinations. 932 * XXX: we currently do not consider if an appropriate route exists. 933 */ 934 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 935 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 936 return(-1); 937 } 938 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 939 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 940 return(1); 941 } 942 943 /* Rule 2: Prefer matching scope. */ 944 if (dst1->aio_dstscope == dst1->aio_srcscope && 945 dst2->aio_dstscope != dst2->aio_srcscope) { 946 return(-1); 947 } 948 if (dst1->aio_dstscope != dst1->aio_srcscope && 949 dst2->aio_dstscope == dst2->aio_srcscope) { 950 return(1); 951 } 952 953 /* Rule 3: Avoid deprecated addresses. */ 954 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 955 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 956 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 957 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 958 return(-1); 959 } 960 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 961 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 962 return(1); 963 } 964 } 965 966 /* Rule 4: Prefer home addresses. */ 967 /* XXX: not implemented yet */ 968 969 /* Rule 5: Prefer matching label. */ 970#ifdef INET6 971 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 972 dst1->aio_srcpolicy->pc_policy.label == 973 dst1->aio_dstpolicy->pc_policy.label && 974 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 975 dst2->aio_srcpolicy->pc_policy.label != 976 dst2->aio_dstpolicy->pc_policy.label)) { 977 return(-1); 978 } 979 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 980 dst2->aio_srcpolicy->pc_policy.label == 981 dst2->aio_dstpolicy->pc_policy.label && 982 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 983 dst1->aio_srcpolicy->pc_policy.label != 984 dst1->aio_dstpolicy->pc_policy.label)) { 985 return(1); 986 } 987#endif 988 989 /* Rule 6: Prefer higher precedence. */ 990#ifdef INET6 991 if (dst1->aio_dstpolicy && 992 (dst2->aio_dstpolicy == NULL || 993 dst1->aio_dstpolicy->pc_policy.preced > 994 dst2->aio_dstpolicy->pc_policy.preced)) { 995 return(-1); 996 } 997 if (dst2->aio_dstpolicy && 998 (dst1->aio_dstpolicy == NULL || 999 dst2->aio_dstpolicy->pc_policy.preced > 1000 dst1->aio_dstpolicy->pc_policy.preced)) { 1001 return(1); 1002 } 1003#endif 1004 1005 /* Rule 7: Prefer native transport. */ 1006 /* XXX: not implemented yet */ 1007 1008 /* Rule 8: Prefer smaller scope. */ 1009 if (dst1->aio_dstscope >= 0 && 1010 dst1->aio_dstscope < dst2->aio_dstscope) { 1011 return(-1); 1012 } 1013 if (dst2->aio_dstscope >= 0 && 1014 dst2->aio_dstscope < dst1->aio_dstscope) { 1015 return(1); 1016 } 1017 1018 /* 1019 * Rule 9: Use longest matching prefix. 1020 * We compare the match length in a same AF only. 1021 */ 1022 if (dst1->aio_ai->ai_addr->sa_family == 1023 dst2->aio_ai->ai_addr->sa_family) { 1024 if (dst1->aio_matchlen > dst2->aio_matchlen) { 1025 return(-1); 1026 } 1027 if (dst1->aio_matchlen < dst2->aio_matchlen) { 1028 return(1); 1029 } 1030 } 1031 1032 /* Rule 10: Otherwise, leave the order unchanged. */ 1033 return(-1); 1034} 1035 1036/* 1037 * Copy from scope.c. 1038 * XXX: we should standardize the functions and link them as standard 1039 * library. 1040 */ 1041static int 1042gai_addr2scopetype(sa) 1043 struct sockaddr *sa; 1044{ 1045#ifdef INET6 1046 struct sockaddr_in6 *sa6; 1047#endif 1048 struct sockaddr_in *sa4; 1049 1050 switch(sa->sa_family) { 1051#ifdef INET6 1052 case AF_INET6: 1053 sa6 = (struct sockaddr_in6 *)sa; 1054 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1055 /* just use the scope field of the multicast address */ 1056 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1057 } 1058 /* 1059 * Unicast addresses: map scope type to corresponding scope 1060 * value defined for multcast addresses. 1061 * XXX: hardcoded scope type values are bad... 1062 */ 1063 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1064 return(1); /* node local scope */ 1065 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1066 return(2); /* link-local scope */ 1067 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1068 return(5); /* site-local scope */ 1069 return(14); /* global scope */ 1070 break; 1071#endif 1072 case AF_INET: 1073 /* 1074 * IPv4 pseudo scoping according to RFC 3484. 1075 */ 1076 sa4 = (struct sockaddr_in *)sa; 1077 /* IPv4 autoconfiguration addresses have link-local scope. */ 1078 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1079 ((u_char *)&sa4->sin_addr)[1] == 254) 1080 return(2); 1081 /* Private addresses have site-local scope. */ 1082 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1083 (((u_char *)&sa4->sin_addr)[0] == 172 && 1084 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1085 (((u_char *)&sa4->sin_addr)[0] == 192 && 1086 ((u_char *)&sa4->sin_addr)[1] == 168)) 1087 return(14); /* XXX: It should be 5 unless NAT */ 1088 /* Loopback addresses have link-local scope. */ 1089 if (((u_char *)&sa4->sin_addr)[0] == 127) 1090 return(2); 1091 return(14); 1092 break; 1093 default: 1094 errno = EAFNOSUPPORT; /* is this a good error? */ 1095 return(-1); 1096 } 1097} 1098 1099/* 1100 * hostname == NULL. 1101 * passive socket -> anyaddr (0.0.0.0 or ::) 1102 * non-passive socket -> localhost (127.0.0.1 or ::1) 1103 */ 1104static int 1105explore_null(pai, servname, res) 1106 const struct addrinfo *pai; 1107 const char *servname; 1108 struct addrinfo **res; 1109{ 1110 int s; 1111 const struct afd *afd; 1112 struct addrinfo *cur; 1113 struct addrinfo sentinel; 1114 int error; 1115 1116 *res = NULL; 1117 sentinel.ai_next = NULL; 1118 cur = &sentinel; 1119 1120 /* 1121 * filter out AFs that are not supported by the kernel 1122 * XXX errno? 1123 */ 1124 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1125 if (s < 0) { 1126 if (errno != EMFILE) 1127 return 0; 1128 } else 1129 _close(s); 1130 1131 /* 1132 * if the servname does not match socktype/protocol, ignore it. 1133 */ 1134 if (get_portmatch(pai, servname) != 0) 1135 return 0; 1136 1137 afd = find_afd(pai->ai_family); 1138 if (afd == NULL) 1139 return 0; 1140 1141 if (pai->ai_flags & AI_PASSIVE) { 1142 GET_AI(cur->ai_next, afd, afd->a_addrany); 1143 /* xxx meaningless? 1144 * GET_CANONNAME(cur->ai_next, "anyaddr"); 1145 */ 1146 GET_PORT(cur->ai_next, servname); 1147 } else { 1148 GET_AI(cur->ai_next, afd, afd->a_loopback); 1149 /* xxx meaningless? 1150 * GET_CANONNAME(cur->ai_next, "localhost"); 1151 */ 1152 GET_PORT(cur->ai_next, servname); 1153 } 1154 cur = cur->ai_next; 1155 1156 *res = sentinel.ai_next; 1157 return 0; 1158 1159free: 1160 if (sentinel.ai_next) 1161 freeaddrinfo(sentinel.ai_next); 1162 return error; 1163} 1164 1165/* 1166 * numeric hostname 1167 */ 1168static int 1169explore_numeric(pai, hostname, servname, res, canonname) 1170 const struct addrinfo *pai; 1171 const char *hostname; 1172 const char *servname; 1173 struct addrinfo **res; 1174 const char *canonname; 1175{ 1176 const struct afd *afd; 1177 struct addrinfo *cur; 1178 struct addrinfo sentinel; 1179 int error; 1180 char pton[PTON_MAX]; 1181 1182 *res = NULL; 1183 sentinel.ai_next = NULL; 1184 cur = &sentinel; 1185 1186 /* 1187 * if the servname does not match socktype/protocol, ignore it. 1188 */ 1189 if (get_portmatch(pai, servname) != 0) 1190 return 0; 1191 1192 afd = find_afd(pai->ai_family); 1193 if (afd == NULL) 1194 return 0; 1195 1196 switch (afd->a_af) { 1197#if 1 /*X/Open spec*/ 1198 case AF_INET: 1199 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 1200 if (pai->ai_family == afd->a_af || 1201 pai->ai_family == PF_UNSPEC /*?*/) { 1202 GET_AI(cur->ai_next, afd, pton); 1203 GET_PORT(cur->ai_next, servname); 1204 if ((pai->ai_flags & AI_CANONNAME)) { 1205 /* 1206 * Set the numeric address itself as 1207 * the canonical name, based on a 1208 * clarification in rfc3493. 1209 */ 1210 GET_CANONNAME(cur->ai_next, canonname); 1211 } 1212 while (cur && cur->ai_next) 1213 cur = cur->ai_next; 1214 } else 1215 ERR(EAI_FAMILY); /*xxx*/ 1216 } 1217 break; 1218#endif 1219 default: 1220 if (inet_pton(afd->a_af, hostname, pton) == 1) { 1221 if (pai->ai_family == afd->a_af || 1222 pai->ai_family == PF_UNSPEC /*?*/) { 1223 GET_AI(cur->ai_next, afd, pton); 1224 GET_PORT(cur->ai_next, servname); 1225 if ((pai->ai_flags & AI_CANONNAME)) { 1226 /* 1227 * Set the numeric address itself as 1228 * the canonical name, based on a 1229 * clarification in rfc3493. 1230 */ 1231 GET_CANONNAME(cur->ai_next, canonname); 1232 } 1233 while (cur && cur->ai_next) 1234 cur = cur->ai_next; 1235 } else 1236 ERR(EAI_FAMILY); /* XXX */ 1237 } 1238 break; 1239 } 1240 1241 *res = sentinel.ai_next; 1242 return 0; 1243 1244free: 1245bad: 1246 if (sentinel.ai_next) 1247 freeaddrinfo(sentinel.ai_next); 1248 return error; 1249} 1250 1251/* 1252 * numeric hostname with scope 1253 */ 1254static int 1255explore_numeric_scope(pai, hostname, servname, res) 1256 const struct addrinfo *pai; 1257 const char *hostname; 1258 const char *servname; 1259 struct addrinfo **res; 1260{ 1261#if !defined(SCOPE_DELIMITER) || !defined(INET6) 1262 return explore_numeric(pai, hostname, servname, res, hostname); 1263#else 1264 const struct afd *afd; 1265 struct addrinfo *cur; 1266 int error; 1267 char *cp, *hostname2 = NULL, *scope, *addr; 1268 struct sockaddr_in6 *sin6; 1269 1270 /* 1271 * if the servname does not match socktype/protocol, ignore it. 1272 */ 1273 if (get_portmatch(pai, servname) != 0) 1274 return 0; 1275 1276 afd = find_afd(pai->ai_family); 1277 if (afd == NULL) 1278 return 0; 1279 1280 if (!afd->a_scoped) 1281 return explore_numeric(pai, hostname, servname, res, hostname); 1282 1283 cp = strchr(hostname, SCOPE_DELIMITER); 1284 if (cp == NULL) 1285 return explore_numeric(pai, hostname, servname, res, hostname); 1286 1287 /* 1288 * Handle special case of <scoped_address><delimiter><scope id> 1289 */ 1290 hostname2 = strdup(hostname); 1291 if (hostname2 == NULL) 1292 return EAI_MEMORY; 1293 /* terminate at the delimiter */ 1294 hostname2[cp - hostname] = '\0'; 1295 addr = hostname2; 1296 scope = cp + 1; 1297 1298 error = explore_numeric(pai, addr, servname, res, hostname); 1299 if (error == 0) { 1300 u_int32_t scopeid; 1301 1302 for (cur = *res; cur; cur = cur->ai_next) { 1303 if (cur->ai_family != AF_INET6) 1304 continue; 1305 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1306 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1307 free(hostname2); 1308 return(EAI_NONAME); /* XXX: is return OK? */ 1309 } 1310 sin6->sin6_scope_id = scopeid; 1311 } 1312 } 1313 1314 free(hostname2); 1315 1316 return error; 1317#endif 1318} 1319 1320static int 1321get_canonname(pai, ai, str) 1322 const struct addrinfo *pai; 1323 struct addrinfo *ai; 1324 const char *str; 1325{ 1326 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1327 ai->ai_canonname = strdup(str); 1328 if (ai->ai_canonname == NULL) 1329 return EAI_MEMORY; 1330 } 1331 return 0; 1332} 1333 1334static struct addrinfo * 1335get_ai(pai, afd, addr) 1336 const struct addrinfo *pai; 1337 const struct afd *afd; 1338 const char *addr; 1339{ 1340 char *p; 1341 struct addrinfo *ai; 1342#ifdef FAITH 1343 struct in6_addr faith_prefix; 1344 char *fp_str; 1345 int translate = 0; 1346#endif 1347 1348#ifdef FAITH 1349 /* 1350 * Transfrom an IPv4 addr into a special IPv6 addr format for 1351 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1352 * 1353 * +-----------------------------------+------------+ 1354 * | faith prefix part (12 bytes) | embedded | 1355 * | | IPv4 addr part (4 bytes) 1356 * +-----------------------------------+------------+ 1357 * 1358 * faith prefix part is specified as ascii IPv6 addr format 1359 * in environmental variable GAI. 1360 * For FAITH to work correctly, routing to faith prefix must be 1361 * setup toward a machine where a FAITH daemon operates. 1362 * Also, the machine must enable some mechanizm 1363 * (e.g. faith interface hack) to divert those packet with 1364 * faith prefixed destination addr to user-land FAITH daemon. 1365 */ 1366 fp_str = getenv("GAI"); 1367 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1368 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1369 u_int32_t v4a; 1370 u_int8_t v4a_top; 1371 1372 memcpy(&v4a, addr, sizeof v4a); 1373 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1374 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1375 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1376 afd = &afdl[N_INET6]; 1377 memcpy(&faith_prefix.s6_addr[12], addr, 1378 sizeof(struct in_addr)); 1379 translate = 1; 1380 } 1381 } 1382#endif 1383 1384 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1385 + (afd->a_socklen)); 1386 if (ai == NULL) 1387 return NULL; 1388 1389 memcpy(ai, pai, sizeof(struct addrinfo)); 1390 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1391 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1392 ai->ai_addr->sa_len = afd->a_socklen; 1393 ai->ai_addrlen = afd->a_socklen; 1394 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1395 p = (char *)(void *)(ai->ai_addr); 1396#ifdef FAITH 1397 if (translate == 1) 1398 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1399 else 1400#endif 1401 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1402 return ai; 1403} 1404 1405static int 1406get_portmatch(ai, servname) 1407 const struct addrinfo *ai; 1408 const char *servname; 1409{ 1410 1411 /* get_port does not touch first argument when matchonly == 1. */ 1412 /* LINTED const cast */ 1413 return get_port((struct addrinfo *)ai, servname, 1); 1414} 1415 1416static int 1417get_port(ai, servname, matchonly) 1418 struct addrinfo *ai; 1419 const char *servname; 1420 int matchonly; 1421{ 1422 const char *proto; 1423 struct servent *sp; 1424 int port; 1425 int allownumeric; 1426 1427 if (servname == NULL) 1428 return 0; 1429 switch (ai->ai_family) { 1430 case AF_INET: 1431#ifdef AF_INET6 1432 case AF_INET6: 1433#endif 1434 break; 1435 default: 1436 return 0; 1437 } 1438 1439 switch (ai->ai_socktype) { 1440 case SOCK_RAW: 1441 return EAI_SERVICE; 1442 case SOCK_DGRAM: 1443 case SOCK_STREAM: 1444 allownumeric = 1; 1445 break; 1446 case ANY: 1447 allownumeric = 0; 1448 break; 1449 default: 1450 return EAI_SOCKTYPE; 1451 } 1452 1453 port = str2number(servname); 1454 if (port >= 0) { 1455 if (!allownumeric) 1456 return EAI_SERVICE; 1457 if (port < 0 || port > 65535) 1458 return EAI_SERVICE; 1459 port = htons(port); 1460 } else { 1461 if (ai->ai_flags & AI_NUMERICSERV) 1462 return EAI_NONAME; 1463 switch (ai->ai_socktype) { 1464 case SOCK_DGRAM: 1465 proto = "udp"; 1466 break; 1467 case SOCK_STREAM: 1468 proto = "tcp"; 1469 break; 1470 default: 1471 proto = NULL; 1472 break; 1473 } 1474 1475 THREAD_LOCK(); 1476 if ((sp = getservbyname(servname, proto)) == NULL) { 1477 THREAD_UNLOCK(); 1478 return EAI_SERVICE; 1479 } 1480 port = sp->s_port; 1481 THREAD_UNLOCK(); 1482 } 1483 1484 if (!matchonly) { 1485 switch (ai->ai_family) { 1486 case AF_INET: 1487 ((struct sockaddr_in *)(void *) 1488 ai->ai_addr)->sin_port = port; 1489 break; 1490#ifdef INET6 1491 case AF_INET6: 1492 ((struct sockaddr_in6 *)(void *) 1493 ai->ai_addr)->sin6_port = port; 1494 break; 1495#endif 1496 } 1497 } 1498 1499 return 0; 1500} 1501 1502static const struct afd * 1503find_afd(af) 1504 int af; 1505{ 1506 const struct afd *afd; 1507 1508 if (af == PF_UNSPEC) 1509 return NULL; 1510 for (afd = afdl; afd->a_af; afd++) { 1511 if (afd->a_af == af) 1512 return afd; 1513 } 1514 return NULL; 1515} 1516 1517/* 1518 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1519 * will take care of it. 1520 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1521 * if the code is right or not. 1522 * 1523 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1524 * _dns_getaddrinfo. 1525 */ 1526static int 1527addrconfig(pai) 1528 struct addrinfo *pai; 1529{ 1530 int s, af; 1531 1532 /* 1533 * TODO: 1534 * Note that implementation dependent test for address 1535 * configuration should be done everytime called 1536 * (or apropriate interval), 1537 * because addresses will be dynamically assigned or deleted. 1538 */ 1539 af = pai->ai_family; 1540 if (af == AF_UNSPEC) { 1541 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1542 af = AF_INET; 1543 else { 1544 _close(s); 1545 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1546 af = AF_INET6; 1547 else 1548 _close(s); 1549 } 1550 } 1551 if (af != AF_UNSPEC) { 1552 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1553 return 0; 1554 _close(s); 1555 } 1556 pai->ai_family = af; 1557 return 1; 1558} 1559 1560#ifdef INET6 1561/* convert a string to a scope identifier. XXX: IPv6 specific */ 1562static int 1563ip6_str2scopeid(scope, sin6, scopeid) 1564 char *scope; 1565 struct sockaddr_in6 *sin6; 1566 u_int32_t *scopeid; 1567{ 1568 u_long lscopeid; 1569 struct in6_addr *a6; 1570 char *ep; 1571 1572 a6 = &sin6->sin6_addr; 1573 1574 /* empty scopeid portion is invalid */ 1575 if (*scope == '\0') 1576 return -1; 1577 1578 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1579 /* 1580 * We currently assume a one-to-one mapping between links 1581 * and interfaces, so we simply use interface indices for 1582 * like-local scopes. 1583 */ 1584 *scopeid = if_nametoindex(scope); 1585 if (*scopeid == 0) 1586 goto trynumeric; 1587 return 0; 1588 } 1589 1590 /* still unclear about literal, allow numeric only - placeholder */ 1591 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1592 goto trynumeric; 1593 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1594 goto trynumeric; 1595 else 1596 goto trynumeric; /* global */ 1597 1598 /* try to convert to a numeric id as a last resort */ 1599 trynumeric: 1600 errno = 0; 1601 lscopeid = strtoul(scope, &ep, 10); 1602 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1603 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1604 return 0; 1605 else 1606 return -1; 1607} 1608#endif 1609 1610/* 1611 * FQDN hostname, DNS lookup 1612 */ 1613static int 1614explore_fqdn(pai, hostname, servname, res) 1615 const struct addrinfo *pai; 1616 const char *hostname; 1617 const char *servname; 1618 struct addrinfo **res; 1619{ 1620 struct addrinfo *result; 1621 struct addrinfo *cur; 1622 int error = 0; 1623 static const ns_dtab dtab[] = { 1624 NS_FILES_CB(_files_getaddrinfo, NULL) 1625 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1626 NS_NIS_CB(_yp_getaddrinfo, NULL) 1627 { 0 } 1628 }; 1629 1630 result = NULL; 1631 1632 /* 1633 * if the servname does not match socktype/protocol, ignore it. 1634 */ 1635 if (get_portmatch(pai, servname) != 0) 1636 return 0; 1637 1638 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1639 default_dns_files, hostname, pai)) { 1640 case NS_TRYAGAIN: 1641 error = EAI_AGAIN; 1642 goto free; 1643 case NS_UNAVAIL: 1644 error = EAI_FAIL; 1645 goto free; 1646 case NS_NOTFOUND: 1647 error = EAI_NONAME; 1648 goto free; 1649 case NS_SUCCESS: 1650 error = 0; 1651 for (cur = result; cur; cur = cur->ai_next) { 1652 GET_PORT(cur, servname); 1653 /* canonname should be filled already */ 1654 } 1655 break; 1656 } 1657 1658 *res = result; 1659 1660 return 0; 1661 1662free: 1663 if (result) 1664 freeaddrinfo(result); 1665 return error; 1666} 1667 1668#ifdef DEBUG 1669static const char AskedForGot[] = 1670 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1671#endif 1672 1673static struct addrinfo * 1674getanswer(answer, anslen, qname, qtype, pai) 1675 const querybuf *answer; 1676 int anslen; 1677 const char *qname; 1678 int qtype; 1679 const struct addrinfo *pai; 1680{ 1681 struct addrinfo sentinel, *cur; 1682 struct addrinfo ai; 1683 const struct afd *afd; 1684 char *canonname; 1685 const HEADER *hp; 1686 const u_char *cp; 1687 int n; 1688 const u_char *eom; 1689 char *bp, *ep; 1690 int type, class, ancount, qdcount; 1691 int haveanswer, had_error; 1692 char tbuf[MAXDNAME]; 1693 int (*name_ok)(const char *); 1694 char hostbuf[8*1024]; 1695 1696 memset(&sentinel, 0, sizeof(sentinel)); 1697 cur = &sentinel; 1698 1699 canonname = NULL; 1700 eom = answer->buf + anslen; 1701 switch (qtype) { 1702 case T_A: 1703 case T_AAAA: 1704 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1705 name_ok = res_hnok; 1706 break; 1707 default: 1708 return (NULL); /* XXX should be abort(); */ 1709 } 1710 /* 1711 * find first satisfactory answer 1712 */ 1713 hp = &answer->hdr; 1714 ancount = ntohs(hp->ancount); 1715 qdcount = ntohs(hp->qdcount); 1716 bp = hostbuf; 1717 ep = hostbuf + sizeof hostbuf; 1718 cp = answer->buf + HFIXEDSZ; 1719 if (qdcount != 1) { 1720 h_errno = NO_RECOVERY; 1721 return (NULL); 1722 } 1723 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1724 if ((n < 0) || !(*name_ok)(bp)) { 1725 h_errno = NO_RECOVERY; 1726 return (NULL); 1727 } 1728 cp += n + QFIXEDSZ; 1729 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1730 /* res_send() has already verified that the query name is the 1731 * same as the one we sent; this just gets the expanded name 1732 * (i.e., with the succeeding search-domain tacked on). 1733 */ 1734 n = strlen(bp) + 1; /* for the \0 */ 1735 if (n >= MAXHOSTNAMELEN) { 1736 h_errno = NO_RECOVERY; 1737 return (NULL); 1738 } 1739 canonname = bp; 1740 bp += n; 1741 /* The qname can be abbreviated, but h_name is now absolute. */ 1742 qname = canonname; 1743 } 1744 haveanswer = 0; 1745 had_error = 0; 1746 while (ancount-- > 0 && cp < eom && !had_error) { 1747 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1748 if ((n < 0) || !(*name_ok)(bp)) { 1749 had_error++; 1750 continue; 1751 } 1752 cp += n; /* name */ 1753 type = _getshort(cp); 1754 cp += INT16SZ; /* type */ 1755 class = _getshort(cp); 1756 cp += INT16SZ + INT32SZ; /* class, TTL */ 1757 n = _getshort(cp); 1758 cp += INT16SZ; /* len */ 1759 if (class != C_IN) { 1760 /* XXX - debug? syslog? */ 1761 cp += n; 1762 continue; /* XXX - had_error++ ? */ 1763 } 1764 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1765 type == T_CNAME) { 1766 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1767 if ((n < 0) || !(*name_ok)(tbuf)) { 1768 had_error++; 1769 continue; 1770 } 1771 cp += n; 1772 /* Get canonical name. */ 1773 n = strlen(tbuf) + 1; /* for the \0 */ 1774 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1775 had_error++; 1776 continue; 1777 } 1778 strlcpy(bp, tbuf, ep - bp); 1779 canonname = bp; 1780 bp += n; 1781 continue; 1782 } 1783 if (qtype == T_ANY) { 1784 if (!(type == T_A || type == T_AAAA)) { 1785 cp += n; 1786 continue; 1787 } 1788 } else if (type != qtype) { 1789#ifdef DEBUG 1790 if (type != T_KEY && type != T_SIG) 1791 syslog(LOG_NOTICE|LOG_AUTH, 1792 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1793 qname, p_class(C_IN), p_type(qtype), 1794 p_type(type)); 1795#endif 1796 cp += n; 1797 continue; /* XXX - had_error++ ? */ 1798 } 1799 switch (type) { 1800 case T_A: 1801 case T_AAAA: 1802 if (strcasecmp(canonname, bp) != 0) { 1803#ifdef DEBUG 1804 syslog(LOG_NOTICE|LOG_AUTH, 1805 AskedForGot, canonname, bp); 1806#endif 1807 cp += n; 1808 continue; /* XXX - had_error++ ? */ 1809 } 1810 if (type == T_A && n != INADDRSZ) { 1811 cp += n; 1812 continue; 1813 } 1814 if (type == T_AAAA && n != IN6ADDRSZ) { 1815 cp += n; 1816 continue; 1817 } 1818#ifdef FILTER_V4MAPPED 1819 if (type == T_AAAA) { 1820 struct in6_addr in6; 1821 memcpy(&in6, cp, sizeof(in6)); 1822 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1823 cp += n; 1824 continue; 1825 } 1826 } 1827#endif 1828 if (!haveanswer) { 1829 int nn; 1830 1831 canonname = bp; 1832 nn = strlen(bp) + 1; /* for the \0 */ 1833 bp += nn; 1834 } 1835 1836 /* don't overwrite pai */ 1837 ai = *pai; 1838 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1839 afd = find_afd(ai.ai_family); 1840 if (afd == NULL) { 1841 cp += n; 1842 continue; 1843 } 1844 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1845 if (cur->ai_next == NULL) 1846 had_error++; 1847 while (cur && cur->ai_next) 1848 cur = cur->ai_next; 1849 cp += n; 1850 break; 1851 default: 1852 abort(); 1853 } 1854 if (!had_error) 1855 haveanswer++; 1856 } 1857 if (haveanswer) { 1858#if defined(RESOLVSORT) 1859 /* 1860 * We support only IPv4 address for backward 1861 * compatibility against gethostbyname(3). 1862 */ 1863 if (_res.nsort && qtype == T_A) { 1864 if (addr4sort(&sentinel) < 0) { 1865 freeaddrinfo(sentinel.ai_next); 1866 h_errno = NO_RECOVERY; 1867 return NULL; 1868 } 1869 } 1870#endif /*RESOLVSORT*/ 1871 if (!canonname) 1872 (void)get_canonname(pai, sentinel.ai_next, qname); 1873 else 1874 (void)get_canonname(pai, sentinel.ai_next, canonname); 1875 h_errno = NETDB_SUCCESS; 1876 return sentinel.ai_next; 1877 } 1878 1879 h_errno = NO_RECOVERY; 1880 return NULL; 1881} 1882 1883#ifdef RESOLVSORT 1884struct addr_ptr { 1885 struct addrinfo *ai; 1886 int aval; 1887}; 1888 1889static int 1890addr4sort(struct addrinfo *sentinel) 1891{ 1892 struct addrinfo *ai; 1893 struct addr_ptr *addrs, addr; 1894 struct sockaddr_in *sin; 1895 int naddrs, i, j; 1896 int needsort = 0; 1897 1898 if (!sentinel) 1899 return -1; 1900 naddrs = 0; 1901 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1902 naddrs++; 1903 if (naddrs < 2) 1904 return 0; /* We don't need sorting. */ 1905 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1906 return -1; 1907 i = 0; 1908 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1909 sin = (struct sockaddr_in *)ai->ai_addr; 1910 for (j = 0; (unsigned)j < _res.nsort; j++) { 1911 if (_res.sort_list[j].addr.s_addr == 1912 (sin->sin_addr.s_addr & _res.sort_list[j].mask)) 1913 break; 1914 } 1915 addrs[i].ai = ai; 1916 addrs[i].aval = j; 1917 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1918 needsort = i; 1919 i++; 1920 } 1921 if (!needsort) { 1922 free(addrs); 1923 return 0; 1924 } 1925 1926 while (needsort < naddrs) { 1927 for (j = needsort - 1; j >= 0; j--) { 1928 if (addrs[j].aval > addrs[j+1].aval) { 1929 addr = addrs[j]; 1930 addrs[j] = addrs[j + 1]; 1931 addrs[j + 1] = addr; 1932 } else 1933 break; 1934 } 1935 needsort++; 1936 } 1937 1938 ai = sentinel; 1939 for (i = 0; i < naddrs; ++i) { 1940 ai->ai_next = addrs[i].ai; 1941 ai = ai->ai_next; 1942 } 1943 ai->ai_next = NULL; 1944 free(addrs); 1945 return 0; 1946} 1947#endif /*RESOLVSORT*/ 1948 1949/*ARGSUSED*/ 1950static int 1951_dns_getaddrinfo(rv, cb_data, ap) 1952 void *rv; 1953 void *cb_data; 1954 va_list ap; 1955{ 1956 struct addrinfo *ai; 1957 querybuf *buf, *buf2; 1958 const char *hostname; 1959 const struct addrinfo *pai; 1960 struct addrinfo sentinel, *cur; 1961 struct res_target q, q2; 1962 1963 hostname = va_arg(ap, char *); 1964 pai = va_arg(ap, const struct addrinfo *); 1965 1966 memset(&q, 0, sizeof(q2)); 1967 memset(&q2, 0, sizeof(q2)); 1968 memset(&sentinel, 0, sizeof(sentinel)); 1969 cur = &sentinel; 1970 1971 buf = malloc(sizeof(*buf)); 1972 if (!buf) { 1973 h_errno = NETDB_INTERNAL; 1974 return NS_NOTFOUND; 1975 } 1976 buf2 = malloc(sizeof(*buf2)); 1977 if (!buf2) { 1978 free(buf); 1979 h_errno = NETDB_INTERNAL; 1980 return NS_NOTFOUND; 1981 } 1982 1983 switch (pai->ai_family) { 1984 case AF_UNSPEC: 1985 q.name = hostname; 1986 q.qclass = C_IN; 1987 q.qtype = T_A; 1988 q.answer = buf->buf; 1989 q.anslen = sizeof(buf->buf); 1990 q.next = &q2; 1991 q2.name = hostname; 1992 q2.qclass = C_IN; 1993 q2.qtype = T_AAAA; 1994 q2.answer = buf2->buf; 1995 q2.anslen = sizeof(buf2->buf); 1996 break; 1997 case AF_INET: 1998 q.name = hostname; 1999 q.qclass = C_IN; 2000 q.qtype = T_A; 2001 q.answer = buf->buf; 2002 q.anslen = sizeof(buf->buf); 2003 break; 2004 case AF_INET6: 2005 q.name = hostname; 2006 q.qclass = C_IN; 2007 q.qtype = T_AAAA; 2008 q.answer = buf->buf; 2009 q.anslen = sizeof(buf->buf); 2010 break; 2011 default: 2012 free(buf); 2013 free(buf2); 2014 return NS_UNAVAIL; 2015 } 2016 if (res_searchN(hostname, &q) < 0) { 2017 free(buf); 2018 free(buf2); 2019 return NS_NOTFOUND; 2020 } 2021 /* prefer IPv6 */ 2022 if (q.next) { 2023 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai); 2024 if (ai) { 2025 cur->ai_next = ai; 2026 while (cur && cur->ai_next) 2027 cur = cur->ai_next; 2028 } 2029 } 2030 ai = getanswer(buf, q.n, q.name, q.qtype, pai); 2031 if (ai) 2032 cur->ai_next = ai; 2033 free(buf); 2034 free(buf2); 2035 if (sentinel.ai_next == NULL) 2036 switch (h_errno) { 2037 case HOST_NOT_FOUND: 2038 return NS_NOTFOUND; 2039 case TRY_AGAIN: 2040 return NS_TRYAGAIN; 2041 default: 2042 return NS_UNAVAIL; 2043 } 2044 *((struct addrinfo **)rv) = sentinel.ai_next; 2045 return NS_SUCCESS; 2046} 2047 2048static void 2049_sethtent(FILE **hostf) 2050{ 2051 if (!*hostf) 2052 *hostf = fopen(_PATH_HOSTS, "r"); 2053 else 2054 rewind(*hostf); 2055} 2056 2057static void 2058_endhtent(FILE **hostf) 2059{ 2060 if (*hostf) { 2061 (void) fclose(*hostf); 2062 *hostf = NULL; 2063 } 2064} 2065 2066static struct addrinfo * 2067_gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2068{ 2069 char *p; 2070 char *cp, *tname, *cname; 2071 struct addrinfo hints, *res0, *res; 2072 int error; 2073 const char *addr; 2074 char hostbuf[8*1024]; 2075 2076 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "r"))) 2077 return (NULL); 2078again: 2079 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 2080 return (NULL); 2081 if (*p == '#') 2082 goto again; 2083 cp = strpbrk(p, "#\n"); 2084 if (cp != NULL) 2085 *cp = '\0'; 2086 if (!(cp = strpbrk(p, " \t"))) 2087 goto again; 2088 *cp++ = '\0'; 2089 addr = p; 2090 cname = NULL; 2091 /* if this is not something we're looking for, skip it. */ 2092 while (cp && *cp) { 2093 if (*cp == ' ' || *cp == '\t') { 2094 cp++; 2095 continue; 2096 } 2097 tname = cp; 2098 if (cname == NULL) 2099 cname = cp; 2100 if ((cp = strpbrk(cp, " \t")) != NULL) 2101 *cp++ = '\0'; 2102 if (strcasecmp(name, tname) == 0) 2103 goto found; 2104 } 2105 goto again; 2106 2107found: 2108 /* we should not glob socktype/protocol here */ 2109 memset(&hints, 0, sizeof(hints)); 2110 hints.ai_family = pai->ai_family; 2111 hints.ai_socktype = SOCK_DGRAM; 2112 hints.ai_protocol = 0; 2113 hints.ai_flags = AI_NUMERICHOST; 2114 error = getaddrinfo(addr, "0", &hints, &res0); 2115 if (error) 2116 goto again; 2117#ifdef FILTER_V4MAPPED 2118 /* XXX should check all items in the chain */ 2119 if (res0->ai_family == AF_INET6 && 2120 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2121 freeaddrinfo(res0); 2122 goto again; 2123 } 2124#endif 2125 for (res = res0; res; res = res->ai_next) { 2126 /* cover it up */ 2127 res->ai_flags = pai->ai_flags; 2128 res->ai_socktype = pai->ai_socktype; 2129 res->ai_protocol = pai->ai_protocol; 2130 2131 if (pai->ai_flags & AI_CANONNAME) { 2132 if (get_canonname(pai, res, cname) != 0) { 2133 freeaddrinfo(res0); 2134 goto again; 2135 } 2136 } 2137 } 2138 return res0; 2139} 2140 2141/*ARGSUSED*/ 2142static int 2143_files_getaddrinfo(rv, cb_data, ap) 2144 void *rv; 2145 void *cb_data; 2146 va_list ap; 2147{ 2148 const char *name; 2149 const struct addrinfo *pai; 2150 struct addrinfo sentinel, *cur; 2151 struct addrinfo *p; 2152 FILE *hostf = NULL; 2153 2154 name = va_arg(ap, char *); 2155 pai = va_arg(ap, struct addrinfo *); 2156 2157 memset(&sentinel, 0, sizeof(sentinel)); 2158 cur = &sentinel; 2159 2160 _sethtent(&hostf); 2161 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2162 cur->ai_next = p; 2163 while (cur && cur->ai_next) 2164 cur = cur->ai_next; 2165 } 2166 _endhtent(&hostf); 2167 2168 *((struct addrinfo **)rv) = sentinel.ai_next; 2169 if (sentinel.ai_next == NULL) 2170 return NS_NOTFOUND; 2171 return NS_SUCCESS; 2172} 2173 2174#ifdef YP 2175static char *__ypdomain; 2176 2177/*ARGSUSED*/ 2178static struct addrinfo * 2179_yphostent(line, pai) 2180 char *line; 2181 const struct addrinfo *pai; 2182{ 2183 struct addrinfo sentinel, *cur; 2184 struct addrinfo hints, *res, *res0; 2185 int error; 2186 char *p = line; 2187 const char *addr, *canonname; 2188 char *nextline; 2189 char *cp; 2190 2191 addr = canonname = NULL; 2192 2193 memset(&sentinel, 0, sizeof(sentinel)); 2194 cur = &sentinel; 2195 2196nextline: 2197 /* terminate line */ 2198 cp = strchr(p, '\n'); 2199 if (cp) { 2200 *cp++ = '\0'; 2201 nextline = cp; 2202 } else 2203 nextline = NULL; 2204 2205 cp = strpbrk(p, " \t"); 2206 if (cp == NULL) { 2207 if (canonname == NULL) 2208 return (NULL); 2209 else 2210 goto done; 2211 } 2212 *cp++ = '\0'; 2213 2214 addr = p; 2215 2216 while (cp && *cp) { 2217 if (*cp == ' ' || *cp == '\t') { 2218 cp++; 2219 continue; 2220 } 2221 if (!canonname) 2222 canonname = cp; 2223 if ((cp = strpbrk(cp, " \t")) != NULL) 2224 *cp++ = '\0'; 2225 } 2226 2227 hints = *pai; 2228 hints.ai_flags = AI_NUMERICHOST; 2229 error = getaddrinfo(addr, NULL, &hints, &res0); 2230 if (error == 0) { 2231 for (res = res0; res; res = res->ai_next) { 2232 /* cover it up */ 2233 res->ai_flags = pai->ai_flags; 2234 2235 if (pai->ai_flags & AI_CANONNAME) 2236 (void)get_canonname(pai, res, canonname); 2237 } 2238 } else 2239 res0 = NULL; 2240 if (res0) { 2241 cur->ai_next = res0; 2242 while (cur && cur->ai_next) 2243 cur = cur->ai_next; 2244 } 2245 2246 if (nextline) { 2247 p = nextline; 2248 goto nextline; 2249 } 2250 2251done: 2252 return sentinel.ai_next; 2253} 2254 2255/*ARGSUSED*/ 2256static int 2257_yp_getaddrinfo(rv, cb_data, ap) 2258 void *rv; 2259 void *cb_data; 2260 va_list ap; 2261{ 2262 struct addrinfo sentinel, *cur; 2263 struct addrinfo *ai = NULL; 2264 static char *__ypcurrent; 2265 int __ypcurrentlen, r; 2266 const char *name; 2267 const struct addrinfo *pai; 2268 2269 name = va_arg(ap, char *); 2270 pai = va_arg(ap, const struct addrinfo *); 2271 2272 memset(&sentinel, 0, sizeof(sentinel)); 2273 cur = &sentinel; 2274 2275 THREAD_LOCK(); 2276 if (!__ypdomain) { 2277 if (_yp_check(&__ypdomain) == 0) { 2278 THREAD_UNLOCK(); 2279 return NS_UNAVAIL; 2280 } 2281 } 2282 if (__ypcurrent) 2283 free(__ypcurrent); 2284 __ypcurrent = NULL; 2285 2286 /* hosts.byname is only for IPv4 (Solaris8) */ 2287 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2288 r = yp_match(__ypdomain, "hosts.byname", name, 2289 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 2290 if (r == 0) { 2291 struct addrinfo ai4; 2292 2293 ai4 = *pai; 2294 ai4.ai_family = AF_INET; 2295 ai = _yphostent(__ypcurrent, &ai4); 2296 if (ai) { 2297 cur->ai_next = ai; 2298 while (cur && cur->ai_next) 2299 cur = cur->ai_next; 2300 } 2301 } 2302 } 2303 2304 /* ipnodes.byname can hold both IPv4/v6 */ 2305 r = yp_match(__ypdomain, "ipnodes.byname", name, 2306 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 2307 if (r == 0) { 2308 ai = _yphostent(__ypcurrent, pai); 2309 if (ai) { 2310 cur->ai_next = ai; 2311 while (cur && cur->ai_next) 2312 cur = cur->ai_next; 2313 } 2314 } 2315 THREAD_UNLOCK(); 2316 2317 if (sentinel.ai_next == NULL) { 2318 h_errno = HOST_NOT_FOUND; 2319 return NS_NOTFOUND; 2320 } 2321 *((struct addrinfo **)rv) = sentinel.ai_next; 2322 return NS_SUCCESS; 2323} 2324#endif 2325 2326/* resolver logic */ 2327 2328extern const char *__hostalias(const char *); 2329 2330/* 2331 * Formulate a normal query, send, and await answer. 2332 * Returned answer is placed in supplied buffer "answer". 2333 * Perform preliminary check of answer, returning success only 2334 * if no error is indicated and the answer count is nonzero. 2335 * Return the size of the response on success, -1 on error. 2336 * Error number is left in h_errno. 2337 * 2338 * Caller must parse answer and determine whether it answers the question. 2339 */ 2340static int 2341res_queryN(name, target) 2342 const char *name; /* domain name */ 2343 struct res_target *target; 2344{ 2345 u_char *buf; 2346 HEADER *hp; 2347 int n; 2348 struct res_target *t; 2349 int rcode; 2350 int ancount; 2351 2352 rcode = NOERROR; 2353 ancount = 0; 2354 2355 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2356 h_errno = NETDB_INTERNAL; 2357 return (-1); 2358 } 2359 2360 buf = malloc(MAXPACKET); 2361 if (!buf) { 2362 h_errno = NETDB_INTERNAL; 2363 return -1; 2364 } 2365 2366 for (t = target; t; t = t->next) { 2367 int class, type; 2368 u_char *answer; 2369 int anslen; 2370 2371 hp = (HEADER *)(void *)t->answer; 2372 hp->rcode = NOERROR; /* default */ 2373 2374 /* make it easier... */ 2375 class = t->qclass; 2376 type = t->qtype; 2377 answer = t->answer; 2378 anslen = t->anslen; 2379#ifdef DEBUG 2380 if (_res.options & RES_DEBUG) 2381 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2382#endif 2383 2384 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, 2385 buf, MAXPACKET); 2386 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) 2387 n = res_opt(n, buf, MAXPACKET, anslen); 2388 if (n <= 0) { 2389#ifdef DEBUG 2390 if (_res.options & RES_DEBUG) 2391 printf(";; res_query: mkquery failed\n"); 2392#endif 2393 free(buf); 2394 h_errno = NO_RECOVERY; 2395 return (n); 2396 } 2397 n = res_send(buf, n, answer, anslen); 2398#if 0 2399 if (n < 0) { 2400#ifdef DEBUG 2401 if (_res.options & RES_DEBUG) 2402 printf(";; res_query: send error\n"); 2403#endif 2404 free(buf); 2405 h_errno = TRY_AGAIN; 2406 return (n); 2407 } 2408#endif 2409 2410 if (n < 0 || n > anslen) 2411 hp->rcode = FORMERR; /* XXX not very informative */ 2412 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2413 rcode = hp->rcode; /* record most recent error */ 2414#ifdef DEBUG 2415 if (_res.options & RES_DEBUG) 2416 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2417 ntohs(hp->ancount)); 2418#endif 2419 continue; 2420 } 2421 2422 ancount += ntohs(hp->ancount); 2423 2424 t->n = n; 2425 } 2426 2427 free(buf); 2428 2429 if (ancount == 0) { 2430 switch (rcode) { 2431 case NXDOMAIN: 2432 h_errno = HOST_NOT_FOUND; 2433 break; 2434 case SERVFAIL: 2435 h_errno = TRY_AGAIN; 2436 break; 2437 case NOERROR: 2438 h_errno = NO_DATA; 2439 break; 2440 case FORMERR: 2441 case NOTIMP: 2442 case REFUSED: 2443 default: 2444 h_errno = NO_RECOVERY; 2445 break; 2446 } 2447 return (-1); 2448 } 2449 return (ancount); 2450} 2451 2452/* 2453 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2454 * Return the size of the response on success, -1 on error. 2455 * If enabled, implement search rules until answer or unrecoverable failure 2456 * is detected. Error code, if any, is left in h_errno. 2457 */ 2458static int 2459res_searchN(name, target) 2460 const char *name; /* domain name */ 2461 struct res_target *target; 2462{ 2463 const char *cp, * const *domain; 2464 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2465 u_int dots; 2466 int trailing_dot, ret, saved_herrno; 2467 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 2468 2469 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2470 h_errno = NETDB_INTERNAL; 2471 return (-1); 2472 } 2473 2474 errno = 0; 2475 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 2476 dots = 0; 2477 for (cp = name; *cp; cp++) 2478 dots += (*cp == '.'); 2479 trailing_dot = 0; 2480 if (cp > name && *--cp == '.') 2481 trailing_dot++; 2482 2483 /* 2484 * if there aren't any dots, it could be a user-level alias 2485 */ 2486 if (!dots && (cp = __hostalias(name)) != NULL) 2487 return (res_queryN(cp, target)); 2488 2489 /* 2490 * If there are dots in the name already, let's just give it a try 2491 * 'as is'. The threshold can be set with the "ndots" option. 2492 */ 2493 saved_herrno = -1; 2494 if (dots >= _res.ndots) { 2495 ret = res_querydomainN(name, NULL, target); 2496 if (ret > 0) 2497 return (ret); 2498 saved_herrno = h_errno; 2499 tried_as_is++; 2500 } 2501 2502 /* 2503 * We do at least one level of search if 2504 * - there is no dot and RES_DEFNAME is set, or 2505 * - there is at least one dot, there is no trailing dot, 2506 * and RES_DNSRCH is set. 2507 */ 2508 if ((!dots && (_res.options & RES_DEFNAMES)) || 2509 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { 2510 int done = 0; 2511 2512 for (domain = (const char * const *)_res.dnsrch; 2513 *domain && !done; 2514 domain++) { 2515 2516 ret = res_querydomainN(name, *domain, target); 2517 if (ret > 0) 2518 return (ret); 2519 2520 /* 2521 * If no server present, give up. 2522 * If name isn't found in this domain, 2523 * keep trying higher domains in the search list 2524 * (if that's enabled). 2525 * On a NO_DATA error, keep trying, otherwise 2526 * a wildcard entry of another type could keep us 2527 * from finding this entry higher in the domain. 2528 * If we get some other error (negative answer or 2529 * server failure), then stop searching up, 2530 * but try the input name below in case it's 2531 * fully-qualified. 2532 */ 2533 if (errno == ECONNREFUSED) { 2534 h_errno = TRY_AGAIN; 2535 return (-1); 2536 } 2537 2538 switch (h_errno) { 2539 case NO_DATA: 2540 got_nodata++; 2541 /* FALLTHROUGH */ 2542 case HOST_NOT_FOUND: 2543 /* keep trying */ 2544 break; 2545 case TRY_AGAIN: 2546 if (hp->rcode == SERVFAIL) { 2547 /* try next search element, if any */ 2548 got_servfail++; 2549 break; 2550 } 2551 /* FALLTHROUGH */ 2552 default: 2553 /* anything else implies that we're done */ 2554 done++; 2555 } 2556 /* 2557 * if we got here for some reason other than DNSRCH, 2558 * we only wanted one iteration of the loop, so stop. 2559 */ 2560 if (!(_res.options & RES_DNSRCH)) 2561 done++; 2562 } 2563 } 2564 2565 /* 2566 * if we have not already tried the name "as is", do that now. 2567 * note that we do this regardless of how many dots were in the 2568 * name or whether it ends with a dot. 2569 */ 2570 if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) { 2571 ret = res_querydomainN(name, NULL, target); 2572 if (ret > 0) 2573 return (ret); 2574 } 2575 2576 /* 2577 * if we got here, we didn't satisfy the search. 2578 * if we did an initial full query, return that query's h_errno 2579 * (note that we wouldn't be here if that query had succeeded). 2580 * else if we ever got a nodata, send that back as the reason. 2581 * else send back meaningless h_errno, that being the one from 2582 * the last DNSRCH we did. 2583 */ 2584 if (saved_herrno != -1) 2585 h_errno = saved_herrno; 2586 else if (got_nodata) 2587 h_errno = NO_DATA; 2588 else if (got_servfail) 2589 h_errno = TRY_AGAIN; 2590 return (-1); 2591} 2592 2593/* 2594 * Perform a call on res_query on the concatenation of name and domain, 2595 * removing a trailing dot from name if domain is NULL. 2596 */ 2597static int 2598res_querydomainN(name, domain, target) 2599 const char *name, *domain; 2600 struct res_target *target; 2601{ 2602 char nbuf[MAXDNAME]; 2603 const char *longname = nbuf; 2604 size_t n, d; 2605 2606 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2607 h_errno = NETDB_INTERNAL; 2608 return (-1); 2609 } 2610#ifdef DEBUG 2611 if (_res.options & RES_DEBUG) 2612 printf(";; res_querydomain(%s, %s)\n", 2613 name, domain?domain:"<Nil>"); 2614#endif 2615 if (domain == NULL) { 2616 /* 2617 * Check for trailing '.'; 2618 * copy without '.' if present. 2619 */ 2620 n = strlen(name); 2621 if (n >= MAXDNAME) { 2622 h_errno = NO_RECOVERY; 2623 return (-1); 2624 } 2625 if (n > 0 && name[--n] == '.') { 2626 strncpy(nbuf, name, n); 2627 nbuf[n] = '\0'; 2628 } else 2629 longname = name; 2630 } else { 2631 n = strlen(name); 2632 d = strlen(domain); 2633 if (n + d + 1 >= MAXDNAME) { 2634 h_errno = NO_RECOVERY; 2635 return (-1); 2636 } 2637 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2638 } 2639 return (res_queryN(longname, target)); 2640} 2641