getaddrinfo.c revision 160552
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 $GAI. The code does not. 62 */ 63 64#include <sys/cdefs.h> 65__FBSDID("$FreeBSD: head/lib/libc/net/getaddrinfo.c 160552 2006-07-21 19:00:22Z ume $"); 66 67#include "namespace.h" 68#include <sys/types.h> 69#include <sys/param.h> 70#include <sys/socket.h> 71#include <net/if.h> 72#include <netinet/in.h> 73#include <sys/queue.h> 74#ifdef INET6 75#include <net/if_var.h> 76#include <sys/sysctl.h> 77#include <sys/ioctl.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 <resolv.h> 87#include <string.h> 88#include <stdlib.h> 89#include <stddef.h> 90#include <ctype.h> 91#include <unistd.h> 92#include <stdio.h> 93#include <errno.h> 94 95#include "res_config.h" 96 97#ifdef DEBUG 98#include <syslog.h> 99#endif 100 101#include <stdarg.h> 102#include <nsswitch.h> 103#include "un-namespace.h" 104#include "libc_private.h" 105#ifdef NS_CACHING 106#include "nscache.h" 107#endif 108 109#if defined(__KAME__) && defined(INET6) 110# define FAITH 111#endif 112 113#define SUCCESS 0 114#define ANY 0 115#define YES 1 116#define NO 0 117 118static const char in_addrany[] = { 0, 0, 0, 0 }; 119static const char in_loopback[] = { 127, 0, 0, 1 }; 120#ifdef INET6 121static const char in6_addrany[] = { 122 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 123}; 124static const char in6_loopback[] = { 125 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 126}; 127#endif 128 129struct policyqueue { 130 TAILQ_ENTRY(policyqueue) pc_entry; 131#ifdef INET6 132 struct in6_addrpolicy pc_policy; 133#endif 134}; 135TAILQ_HEAD(policyhead, policyqueue); 136 137static const struct afd { 138 int a_af; 139 int a_addrlen; 140 socklen_t a_socklen; 141 int a_off; 142 const char *a_addrany; 143 const char *a_loopback; 144 int a_scoped; 145} afdl [] = { 146#ifdef INET6 147#define N_INET6 0 148 {PF_INET6, sizeof(struct in6_addr), 149 sizeof(struct sockaddr_in6), 150 offsetof(struct sockaddr_in6, sin6_addr), 151 in6_addrany, in6_loopback, 1}, 152#define N_INET 1 153#else 154#define N_INET 0 155#endif 156 {PF_INET, sizeof(struct in_addr), 157 sizeof(struct sockaddr_in), 158 offsetof(struct sockaddr_in, sin_addr), 159 in_addrany, in_loopback, 0}, 160 {0, 0, 0, 0, NULL, NULL, 0}, 161}; 162 163struct explore { 164 int e_af; 165 int e_socktype; 166 int e_protocol; 167 const char *e_protostr; 168 int e_wild; 169#define WILD_AF(ex) ((ex)->e_wild & 0x01) 170#define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 171#define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 172}; 173 174static const struct explore explore[] = { 175#if 0 176 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 177#endif 178#ifdef INET6 179 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 180 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 181 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 182#endif 183 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 184 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 185 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 186 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 187 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 188 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, 189 { -1, 0, 0, NULL, 0 }, 190}; 191 192#ifdef INET6 193#define PTON_MAX 16 194#else 195#define PTON_MAX 4 196#endif 197 198#define AIO_SRCFLAG_DEPRECATED 0x1 199 200struct ai_order { 201 union { 202 struct sockaddr_storage aiou_ss; 203 struct sockaddr aiou_sa; 204 } aio_src_un; 205#define aio_srcsa aio_src_un.aiou_sa 206 u_int32_t aio_srcflag; 207 int aio_srcscope; 208 int aio_dstscope; 209 struct policyqueue *aio_srcpolicy; 210 struct policyqueue *aio_dstpolicy; 211 struct addrinfo *aio_ai; 212 int aio_matchlen; 213}; 214 215static const ns_src default_dns_files[] = { 216 { NSSRC_FILES, NS_SUCCESS }, 217 { NSSRC_DNS, NS_SUCCESS }, 218 { 0 } 219}; 220 221struct res_target { 222 struct res_target *next; 223 const char *name; /* domain name */ 224 int qclass, qtype; /* class and type of query */ 225 u_char *answer; /* buffer to put answer */ 226 int anslen; /* size of answer buffer */ 227 int n; /* result length */ 228}; 229 230#define MAXPACKET (64*1024) 231 232typedef union { 233 HEADER hdr; 234 u_char buf[MAXPACKET]; 235} querybuf; 236 237static int str2number(const char *); 238static int explore_null(const struct addrinfo *, 239 const char *, struct addrinfo **); 240static int explore_numeric(const struct addrinfo *, const char *, 241 const char *, struct addrinfo **, const char *); 242static int explore_numeric_scope(const struct addrinfo *, const char *, 243 const char *, struct addrinfo **); 244static int get_canonname(const struct addrinfo *, 245 struct addrinfo *, const char *); 246static struct addrinfo *get_ai(const struct addrinfo *, 247 const struct afd *, const char *); 248static int get_portmatch(const struct addrinfo *, const char *); 249static int get_port(struct addrinfo *, const char *, int); 250static const struct afd *find_afd(int); 251static int addrconfig(struct addrinfo *); 252static void set_source(struct ai_order *, struct policyhead *); 253static int comp_dst(const void *, const void *); 254#ifdef INET6 255static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 256#endif 257static int gai_addr2scopetype(struct sockaddr *); 258 259static int explore_fqdn(const struct addrinfo *, const char *, 260 const char *, struct addrinfo **); 261 262static int reorder(struct addrinfo *); 263static int get_addrselectpolicy(struct policyhead *); 264static void free_addrselectpolicy(struct policyhead *); 265static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 266 struct policyhead *); 267static int matchlen(struct sockaddr *, struct sockaddr *); 268 269static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 270 const struct addrinfo *, res_state); 271#if defined(RESOLVSORT) 272static int addr4sort(struct addrinfo *, res_state); 273#endif 274static int _dns_getaddrinfo(void *, void *, va_list); 275static void _sethtent(FILE **); 276static void _endhtent(FILE **); 277static struct addrinfo *_gethtent(FILE **, const char *, 278 const struct addrinfo *); 279static int _files_getaddrinfo(void *, void *, va_list); 280#ifdef YP 281static struct addrinfo *_yphostent(char *, const struct addrinfo *); 282static int _yp_getaddrinfo(void *, void *, va_list); 283#endif 284#ifdef NS_CACHING 285static int addrinfo_id_func(char *, size_t *, va_list, void *); 286static int addrinfo_marshal_func(char *, size_t *, void *, va_list, void *); 287static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, void *); 288#endif 289 290static int res_queryN(const char *, struct res_target *, res_state); 291static int res_searchN(const char *, struct res_target *, res_state); 292static int res_querydomainN(const char *, const char *, 293 struct res_target *, res_state); 294 295/* XXX macros that make external reference is BAD. */ 296 297#define GET_AI(ai, afd, addr) \ 298do { \ 299 /* external reference: pai, error, and label free */ \ 300 (ai) = get_ai(pai, (afd), (addr)); \ 301 if ((ai) == NULL) { \ 302 error = EAI_MEMORY; \ 303 goto free; \ 304 } \ 305} while (/*CONSTCOND*/0) 306 307#define GET_PORT(ai, serv) \ 308do { \ 309 /* external reference: error and label free */ \ 310 error = get_port((ai), (serv), 0); \ 311 if (error != 0) \ 312 goto free; \ 313} while (/*CONSTCOND*/0) 314 315#define GET_CANONNAME(ai, str) \ 316do { \ 317 /* external reference: pai, error and label free */ \ 318 error = get_canonname(pai, (ai), (str)); \ 319 if (error != 0) \ 320 goto free; \ 321} while (/*CONSTCOND*/0) 322 323#define ERR(err) \ 324do { \ 325 /* external reference: error, and label bad */ \ 326 error = (err); \ 327 goto bad; \ 328 /*NOTREACHED*/ \ 329} while (/*CONSTCOND*/0) 330 331#define MATCH_FAMILY(x, y, w) \ 332 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 333#define MATCH(x, y, w) \ 334 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 335 336void 337freeaddrinfo(struct addrinfo *ai) 338{ 339 struct addrinfo *next; 340 341 do { 342 next = ai->ai_next; 343 if (ai->ai_canonname) 344 free(ai->ai_canonname); 345 /* no need to free(ai->ai_addr) */ 346 free(ai); 347 ai = next; 348 } while (ai); 349} 350 351static int 352str2number(const char *p) 353{ 354 char *ep; 355 unsigned long v; 356 357 if (*p == '\0') 358 return -1; 359 ep = NULL; 360 errno = 0; 361 v = strtoul(p, &ep, 10); 362 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) 363 return v; 364 else 365 return -1; 366} 367 368int 369getaddrinfo(const char *hostname, const char *servname, 370 const struct addrinfo *hints, struct addrinfo **res) 371{ 372 struct addrinfo sentinel; 373 struct addrinfo *cur; 374 int error = 0; 375 struct addrinfo ai; 376 struct addrinfo ai0; 377 struct addrinfo *pai; 378 const struct explore *ex; 379 int numeric = 0; 380 381 memset(&sentinel, 0, sizeof(sentinel)); 382 cur = &sentinel; 383 pai = &ai; 384 pai->ai_flags = 0; 385 pai->ai_family = PF_UNSPEC; 386 pai->ai_socktype = ANY; 387 pai->ai_protocol = ANY; 388 pai->ai_addrlen = 0; 389 pai->ai_canonname = NULL; 390 pai->ai_addr = NULL; 391 pai->ai_next = NULL; 392 393 if (hostname == NULL && servname == NULL) 394 return EAI_NONAME; 395 if (hints) { 396 /* error check for hints */ 397 if (hints->ai_addrlen || hints->ai_canonname || 398 hints->ai_addr || hints->ai_next) 399 ERR(EAI_BADHINTS); /* xxx */ 400 if (hints->ai_flags & ~AI_MASK) 401 ERR(EAI_BADFLAGS); 402 switch (hints->ai_family) { 403 case PF_UNSPEC: 404 case PF_INET: 405#ifdef INET6 406 case PF_INET6: 407#endif 408 break; 409 default: 410 ERR(EAI_FAMILY); 411 } 412 memcpy(pai, hints, sizeof(*pai)); 413 414 /* 415 * if both socktype/protocol are specified, check if they 416 * are meaningful combination. 417 */ 418 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 419 for (ex = explore; ex->e_af >= 0; ex++) { 420 if (pai->ai_family != ex->e_af) 421 continue; 422 if (ex->e_socktype == ANY) 423 continue; 424 if (ex->e_protocol == ANY) 425 continue; 426 if (pai->ai_socktype == ex->e_socktype && 427 pai->ai_protocol != ex->e_protocol) { 428 ERR(EAI_BADHINTS); 429 } 430 } 431 } 432 } 433 434 /* 435 * post-2553: AI_ALL and AI_V4MAPPED are effective only against 436 * AF_INET6 query. They need to be ignored if specified in other 437 * occassions. 438 */ 439 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 440 case AI_V4MAPPED: 441 case AI_ALL | AI_V4MAPPED: 442 if (pai->ai_family != AF_INET6) 443 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 444 break; 445 case AI_ALL: 446#if 1 447 /* illegal */ 448 ERR(EAI_BADFLAGS); 449#else 450 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 451#endif 452 break; 453 } 454 455 /* 456 * check for special cases. (1) numeric servname is disallowed if 457 * socktype/protocol are left unspecified. (2) servname is disallowed 458 * for raw and other inet{,6} sockets. 459 */ 460 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 461#ifdef PF_INET6 462 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 463#endif 464 ) { 465 ai0 = *pai; /* backup *pai */ 466 467 if (pai->ai_family == PF_UNSPEC) { 468#ifdef PF_INET6 469 pai->ai_family = PF_INET6; 470#else 471 pai->ai_family = PF_INET; 472#endif 473 } 474 error = get_portmatch(pai, servname); 475 if (error) 476 ERR(error); 477 478 *pai = ai0; 479 } 480 481 ai0 = *pai; 482 483 /* NULL hostname, or numeric hostname */ 484 for (ex = explore; ex->e_af >= 0; ex++) { 485 *pai = ai0; 486 487 /* PF_UNSPEC entries are prepared for DNS queries only */ 488 if (ex->e_af == PF_UNSPEC) 489 continue; 490 491 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 492 continue; 493 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 494 continue; 495 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 496 continue; 497 498 if (pai->ai_family == PF_UNSPEC) 499 pai->ai_family = ex->e_af; 500 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 501 pai->ai_socktype = ex->e_socktype; 502 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 503 pai->ai_protocol = ex->e_protocol; 504 505 if (hostname == NULL) 506 error = explore_null(pai, servname, &cur->ai_next); 507 else 508 error = explore_numeric_scope(pai, hostname, servname, 509 &cur->ai_next); 510 511 if (error) 512 goto free; 513 514 while (cur && cur->ai_next) 515 cur = cur->ai_next; 516 } 517 518 /* 519 * XXX 520 * If numreic representation of AF1 can be interpreted as FQDN 521 * representation of AF2, we need to think again about the code below. 522 */ 523 if (sentinel.ai_next) { 524 numeric = 1; 525 goto good; 526 } 527 528 if (hostname == NULL) 529 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 530 if (pai->ai_flags & AI_NUMERICHOST) 531 ERR(EAI_NONAME); 532 533 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 534 ERR(EAI_FAIL); 535 536 /* 537 * hostname as alphabetical name. 538 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 539 * outer loop by AFs. 540 */ 541 for (ex = explore; ex->e_af >= 0; ex++) { 542 *pai = ai0; 543 544 /* require exact match for family field */ 545 if (pai->ai_family != ex->e_af) 546 continue; 547 548 if (!MATCH(pai->ai_socktype, ex->e_socktype, 549 WILD_SOCKTYPE(ex))) { 550 continue; 551 } 552 if (!MATCH(pai->ai_protocol, ex->e_protocol, 553 WILD_PROTOCOL(ex))) { 554 continue; 555 } 556 557 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 558 pai->ai_socktype = ex->e_socktype; 559 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 560 pai->ai_protocol = ex->e_protocol; 561 562 error = explore_fqdn(pai, hostname, servname, 563 &cur->ai_next); 564 565 while (cur && cur->ai_next) 566 cur = cur->ai_next; 567 } 568 569 /* XXX inhibit errors if we have the result */ 570 if (sentinel.ai_next) 571 error = 0; 572 573good: 574 /* 575 * ensure we return either: 576 * - error == 0, non-NULL *res 577 * - error != 0, NULL *res 578 */ 579 if (error == 0) { 580 if (sentinel.ai_next) { 581 /* 582 * If the returned entry is for an active connection, 583 * and the given name is not numeric, reorder the 584 * list, so that the application would try the list 585 * in the most efficient order. 586 */ 587 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 588 if (!numeric) 589 (void)reorder(&sentinel); 590 } 591 *res = sentinel.ai_next; 592 return SUCCESS; 593 } else 594 error = EAI_FAIL; 595 } 596free: 597bad: 598 if (sentinel.ai_next) 599 freeaddrinfo(sentinel.ai_next); 600 *res = NULL; 601 return error; 602} 603 604static int 605reorder(struct addrinfo *sentinel) 606{ 607 struct addrinfo *ai, **aip; 608 struct ai_order *aio; 609 int i, n; 610 struct policyhead policyhead; 611 612 /* count the number of addrinfo elements for sorting. */ 613 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 614 ; 615 616 /* 617 * If the number is small enough, we can skip the reordering process. 618 */ 619 if (n <= 1) 620 return(n); 621 622 /* allocate a temporary array for sort and initialization of it. */ 623 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 624 return(n); /* give up reordering */ 625 memset(aio, 0, sizeof(*aio) * n); 626 627 /* retrieve address selection policy from the kernel */ 628 TAILQ_INIT(&policyhead); 629 if (!get_addrselectpolicy(&policyhead)) { 630 /* no policy is installed into kernel, we don't sort. */ 631 free(aio); 632 return (n); 633 } 634 635 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 636 aio[i].aio_ai = ai; 637 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 638 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 639 &policyhead); 640 set_source(&aio[i], &policyhead); 641 } 642 643 /* perform sorting. */ 644 qsort(aio, n, sizeof(*aio), comp_dst); 645 646 /* reorder the addrinfo chain. */ 647 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 648 *aip = aio[i].aio_ai; 649 aip = &aio[i].aio_ai->ai_next; 650 } 651 *aip = NULL; 652 653 /* cleanup and return */ 654 free(aio); 655 free_addrselectpolicy(&policyhead); 656 return(n); 657} 658 659static int 660get_addrselectpolicy(struct policyhead *head) 661{ 662#ifdef INET6 663 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 664 size_t l; 665 char *buf; 666 struct in6_addrpolicy *pol, *ep; 667 668 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 669 return (0); 670 if ((buf = malloc(l)) == NULL) 671 return (0); 672 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 673 free(buf); 674 return (0); 675 } 676 677 ep = (struct in6_addrpolicy *)(buf + l); 678 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 679 struct policyqueue *new; 680 681 if ((new = malloc(sizeof(*new))) == NULL) { 682 free_addrselectpolicy(head); /* make the list empty */ 683 break; 684 } 685 new->pc_policy = *pol; 686 TAILQ_INSERT_TAIL(head, new, pc_entry); 687 } 688 689 free(buf); 690 return (1); 691#else 692 return (0); 693#endif 694} 695 696static void 697free_addrselectpolicy(struct policyhead *head) 698{ 699 struct policyqueue *ent, *nent; 700 701 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 702 nent = TAILQ_NEXT(ent, pc_entry); 703 TAILQ_REMOVE(head, ent, pc_entry); 704 free(ent); 705 } 706} 707 708static struct policyqueue * 709match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 710{ 711#ifdef INET6 712 struct policyqueue *ent, *bestent = NULL; 713 struct in6_addrpolicy *pol; 714 int matchlen, bestmatchlen = -1; 715 u_char *mp, *ep, *k, *p, m; 716 struct sockaddr_in6 key; 717 718 switch(addr->sa_family) { 719 case AF_INET6: 720 key = *(struct sockaddr_in6 *)addr; 721 break; 722 case AF_INET: 723 /* convert the address into IPv4-mapped IPv6 address. */ 724 memset(&key, 0, sizeof(key)); 725 key.sin6_family = AF_INET6; 726 key.sin6_len = sizeof(key); 727 key.sin6_addr.s6_addr[10] = 0xff; 728 key.sin6_addr.s6_addr[11] = 0xff; 729 memcpy(&key.sin6_addr.s6_addr[12], 730 &((struct sockaddr_in *)addr)->sin_addr, 4); 731 break; 732 default: 733 return(NULL); 734 } 735 736 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 737 pol = &ent->pc_policy; 738 matchlen = 0; 739 740 mp = (u_char *)&pol->addrmask.sin6_addr; 741 ep = mp + 16; /* XXX: scope field? */ 742 k = (u_char *)&key.sin6_addr; 743 p = (u_char *)&pol->addr.sin6_addr; 744 for (; mp < ep && *mp; mp++, k++, p++) { 745 m = *mp; 746 if ((*k & m) != *p) 747 goto next; /* not match */ 748 if (m == 0xff) /* short cut for a typical case */ 749 matchlen += 8; 750 else { 751 while (m >= 0x80) { 752 matchlen++; 753 m <<= 1; 754 } 755 } 756 } 757 758 /* matched. check if this is better than the current best. */ 759 if (matchlen > bestmatchlen) { 760 bestent = ent; 761 bestmatchlen = matchlen; 762 } 763 764 next: 765 continue; 766 } 767 768 return(bestent); 769#else 770 return(NULL); 771#endif 772 773} 774 775static void 776set_source(struct ai_order *aio, struct policyhead *ph) 777{ 778 struct addrinfo ai = *aio->aio_ai; 779 struct sockaddr_storage ss; 780 socklen_t srclen; 781 int s; 782 783 /* set unspec ("no source is available"), just in case */ 784 aio->aio_srcsa.sa_family = AF_UNSPEC; 785 aio->aio_srcscope = -1; 786 787 switch(ai.ai_family) { 788 case AF_INET: 789#ifdef INET6 790 case AF_INET6: 791#endif 792 break; 793 default: /* ignore unsupported AFs explicitly */ 794 return; 795 } 796 797 /* XXX: make a dummy addrinfo to call connect() */ 798 ai.ai_socktype = SOCK_DGRAM; 799 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 800 ai.ai_next = NULL; 801 memset(&ss, 0, sizeof(ss)); 802 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 803 ai.ai_addr = (struct sockaddr *)&ss; 804 get_port(&ai, "1", 0); 805 806 /* open a socket to get the source address for the given dst */ 807 if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0) 808 return; /* give up */ 809 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 810 goto cleanup; 811 srclen = ai.ai_addrlen; 812 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 813 aio->aio_srcsa.sa_family = AF_UNSPEC; 814 goto cleanup; 815 } 816 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 817 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 818 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 819#ifdef INET6 820 if (ai.ai_family == AF_INET6) { 821 struct in6_ifreq ifr6; 822 u_int32_t flags6; 823 824 /* XXX: interface name should not be hardcoded */ 825 strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name)); 826 memset(&ifr6, 0, sizeof(ifr6)); 827 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 828 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 829 flags6 = ifr6.ifr_ifru.ifru_flags6; 830 if ((flags6 & IN6_IFF_DEPRECATED)) 831 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 832 } 833 } 834#endif 835 836 cleanup: 837 _close(s); 838 return; 839} 840 841static int 842matchlen(struct sockaddr *src, struct sockaddr *dst) 843{ 844 int match = 0; 845 u_char *s, *d; 846 u_char *lim, r; 847 int addrlen; 848 849 switch (src->sa_family) { 850#ifdef INET6 851 case AF_INET6: 852 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 853 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 854 addrlen = sizeof(struct in6_addr); 855 lim = s + addrlen; 856 break; 857#endif 858 case AF_INET: 859 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; 860 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; 861 addrlen = sizeof(struct in_addr); 862 lim = s + addrlen; 863 break; 864 default: 865 return(0); 866 } 867 868 while (s < lim) 869 if ((r = (*d++ ^ *s++)) != 0) { 870 while (r < addrlen * 8) { 871 match++; 872 r <<= 1; 873 } 874 break; 875 } else 876 match += 8; 877 return(match); 878} 879 880static int 881comp_dst(const void *arg1, const void *arg2) 882{ 883 const struct ai_order *dst1 = arg1, *dst2 = arg2; 884 885 /* 886 * Rule 1: Avoid unusable destinations. 887 * XXX: we currently do not consider if an appropriate route exists. 888 */ 889 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 890 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 891 return(-1); 892 } 893 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 894 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 895 return(1); 896 } 897 898 /* Rule 2: Prefer matching scope. */ 899 if (dst1->aio_dstscope == dst1->aio_srcscope && 900 dst2->aio_dstscope != dst2->aio_srcscope) { 901 return(-1); 902 } 903 if (dst1->aio_dstscope != dst1->aio_srcscope && 904 dst2->aio_dstscope == dst2->aio_srcscope) { 905 return(1); 906 } 907 908 /* Rule 3: Avoid deprecated addresses. */ 909 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 910 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 911 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 912 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 913 return(-1); 914 } 915 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 916 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 917 return(1); 918 } 919 } 920 921 /* Rule 4: Prefer home addresses. */ 922 /* XXX: not implemented yet */ 923 924 /* Rule 5: Prefer matching label. */ 925#ifdef INET6 926 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 927 dst1->aio_srcpolicy->pc_policy.label == 928 dst1->aio_dstpolicy->pc_policy.label && 929 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 930 dst2->aio_srcpolicy->pc_policy.label != 931 dst2->aio_dstpolicy->pc_policy.label)) { 932 return(-1); 933 } 934 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 935 dst2->aio_srcpolicy->pc_policy.label == 936 dst2->aio_dstpolicy->pc_policy.label && 937 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 938 dst1->aio_srcpolicy->pc_policy.label != 939 dst1->aio_dstpolicy->pc_policy.label)) { 940 return(1); 941 } 942#endif 943 944 /* Rule 6: Prefer higher precedence. */ 945#ifdef INET6 946 if (dst1->aio_dstpolicy && 947 (dst2->aio_dstpolicy == NULL || 948 dst1->aio_dstpolicy->pc_policy.preced > 949 dst2->aio_dstpolicy->pc_policy.preced)) { 950 return(-1); 951 } 952 if (dst2->aio_dstpolicy && 953 (dst1->aio_dstpolicy == NULL || 954 dst2->aio_dstpolicy->pc_policy.preced > 955 dst1->aio_dstpolicy->pc_policy.preced)) { 956 return(1); 957 } 958#endif 959 960 /* Rule 7: Prefer native transport. */ 961 /* XXX: not implemented yet */ 962 963 /* Rule 8: Prefer smaller scope. */ 964 if (dst1->aio_dstscope >= 0 && 965 dst1->aio_dstscope < dst2->aio_dstscope) { 966 return(-1); 967 } 968 if (dst2->aio_dstscope >= 0 && 969 dst2->aio_dstscope < dst1->aio_dstscope) { 970 return(1); 971 } 972 973 /* 974 * Rule 9: Use longest matching prefix. 975 * We compare the match length in a same AF only. 976 */ 977 if (dst1->aio_ai->ai_addr->sa_family == 978 dst2->aio_ai->ai_addr->sa_family) { 979 if (dst1->aio_matchlen > dst2->aio_matchlen) { 980 return(-1); 981 } 982 if (dst1->aio_matchlen < dst2->aio_matchlen) { 983 return(1); 984 } 985 } 986 987 /* Rule 10: Otherwise, leave the order unchanged. */ 988 return(-1); 989} 990 991/* 992 * Copy from scope.c. 993 * XXX: we should standardize the functions and link them as standard 994 * library. 995 */ 996static int 997gai_addr2scopetype(struct sockaddr *sa) 998{ 999#ifdef INET6 1000 struct sockaddr_in6 *sa6; 1001#endif 1002 struct sockaddr_in *sa4; 1003 1004 switch(sa->sa_family) { 1005#ifdef INET6 1006 case AF_INET6: 1007 sa6 = (struct sockaddr_in6 *)sa; 1008 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1009 /* just use the scope field of the multicast address */ 1010 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1011 } 1012 /* 1013 * Unicast addresses: map scope type to corresponding scope 1014 * value defined for multcast addresses. 1015 * XXX: hardcoded scope type values are bad... 1016 */ 1017 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1018 return(1); /* node local scope */ 1019 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1020 return(2); /* link-local scope */ 1021 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1022 return(5); /* site-local scope */ 1023 return(14); /* global scope */ 1024 break; 1025#endif 1026 case AF_INET: 1027 /* 1028 * IPv4 pseudo scoping according to RFC 3484. 1029 */ 1030 sa4 = (struct sockaddr_in *)sa; 1031 /* IPv4 autoconfiguration addresses have link-local scope. */ 1032 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1033 ((u_char *)&sa4->sin_addr)[1] == 254) 1034 return(2); 1035 /* Private addresses have site-local scope. */ 1036 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1037 (((u_char *)&sa4->sin_addr)[0] == 172 && 1038 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1039 (((u_char *)&sa4->sin_addr)[0] == 192 && 1040 ((u_char *)&sa4->sin_addr)[1] == 168)) 1041 return(14); /* XXX: It should be 5 unless NAT */ 1042 /* Loopback addresses have link-local scope. */ 1043 if (((u_char *)&sa4->sin_addr)[0] == 127) 1044 return(2); 1045 return(14); 1046 break; 1047 default: 1048 errno = EAFNOSUPPORT; /* is this a good error? */ 1049 return(-1); 1050 } 1051} 1052 1053/* 1054 * hostname == NULL. 1055 * passive socket -> anyaddr (0.0.0.0 or ::) 1056 * non-passive socket -> localhost (127.0.0.1 or ::1) 1057 */ 1058static int 1059explore_null(const struct addrinfo *pai, const char *servname, 1060 struct addrinfo **res) 1061{ 1062 int s; 1063 const struct afd *afd; 1064 struct addrinfo *ai; 1065 int error; 1066 1067 *res = NULL; 1068 ai = NULL; 1069 1070 /* 1071 * filter out AFs that are not supported by the kernel 1072 * XXX errno? 1073 */ 1074 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1075 if (s < 0) { 1076 if (errno != EMFILE) 1077 return 0; 1078 } else 1079 _close(s); 1080 1081 /* 1082 * if the servname does not match socktype/protocol, ignore it. 1083 */ 1084 if (get_portmatch(pai, servname) != 0) 1085 return 0; 1086 1087 afd = find_afd(pai->ai_family); 1088 if (afd == NULL) 1089 return 0; 1090 1091 if (pai->ai_flags & AI_PASSIVE) { 1092 GET_AI(ai, afd, afd->a_addrany); 1093 GET_PORT(ai, servname); 1094 } else { 1095 GET_AI(ai, afd, afd->a_loopback); 1096 GET_PORT(ai, servname); 1097 } 1098 1099 *res = ai; 1100 return 0; 1101 1102free: 1103 if (ai != NULL) 1104 freeaddrinfo(ai); 1105 return error; 1106} 1107 1108/* 1109 * numeric hostname 1110 */ 1111static int 1112explore_numeric(const struct addrinfo *pai, const char *hostname, 1113 const char *servname, struct addrinfo **res, const char *canonname) 1114{ 1115 const struct afd *afd; 1116 struct addrinfo *ai; 1117 int error; 1118 char pton[PTON_MAX]; 1119 1120 *res = NULL; 1121 ai = NULL; 1122 1123 /* 1124 * if the servname does not match socktype/protocol, ignore it. 1125 */ 1126 if (get_portmatch(pai, servname) != 0) 1127 return 0; 1128 1129 afd = find_afd(pai->ai_family); 1130 if (afd == NULL) 1131 return 0; 1132 1133 switch (afd->a_af) { 1134 case AF_INET: 1135 /* 1136 * RFC3493 requires getaddrinfo() to accept AF_INET formats 1137 * that are accepted by inet_addr() and its family. The 1138 * accepted forms includes the "classful" one, which inet_pton 1139 * does not accept. So we need to separate the case for 1140 * AF_INET. 1141 */ 1142 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 1143 if (pai->ai_family == afd->a_af || 1144 pai->ai_family == PF_UNSPEC /*?*/) { 1145 GET_AI(ai, afd, pton); 1146 GET_PORT(ai, servname); 1147 if ((pai->ai_flags & AI_CANONNAME)) { 1148 /* 1149 * Set the numeric address itself as 1150 * the canonical name, based on a 1151 * clarification in rfc3493. 1152 */ 1153 GET_CANONNAME(ai, canonname); 1154 } 1155 } else 1156 ERR(EAI_FAMILY); /*xxx*/ 1157 } 1158 break; 1159 default: 1160 if (inet_pton(afd->a_af, hostname, pton) == 1) { 1161 if (pai->ai_family == afd->a_af || 1162 pai->ai_family == PF_UNSPEC /*?*/) { 1163 GET_AI(ai, afd, pton); 1164 GET_PORT(ai, servname); 1165 if ((pai->ai_flags & AI_CANONNAME)) { 1166 /* 1167 * Set the numeric address itself as 1168 * the canonical name, based on a 1169 * clarification in rfc3493. 1170 */ 1171 GET_CANONNAME(ai, canonname); 1172 } 1173 } else 1174 ERR(EAI_FAMILY); /* XXX */ 1175 } 1176 break; 1177 } 1178 1179 *res = ai; 1180 return 0; 1181 1182free: 1183bad: 1184 if (ai != NULL) 1185 freeaddrinfo(ai); 1186 return error; 1187} 1188 1189/* 1190 * numeric hostname with scope 1191 */ 1192static int 1193explore_numeric_scope(const struct addrinfo *pai, const char *hostname, 1194 const char *servname, struct addrinfo **res) 1195{ 1196#if !defined(SCOPE_DELIMITER) || !defined(INET6) 1197 return explore_numeric(pai, hostname, servname, res, hostname); 1198#else 1199 const struct afd *afd; 1200 struct addrinfo *cur; 1201 int error; 1202 char *cp, *hostname2 = NULL, *scope, *addr; 1203 struct sockaddr_in6 *sin6; 1204 1205 /* 1206 * if the servname does not match socktype/protocol, ignore it. 1207 */ 1208 if (get_portmatch(pai, servname) != 0) 1209 return 0; 1210 1211 afd = find_afd(pai->ai_family); 1212 if (afd == NULL) 1213 return 0; 1214 1215 if (!afd->a_scoped) 1216 return explore_numeric(pai, hostname, servname, res, hostname); 1217 1218 cp = strchr(hostname, SCOPE_DELIMITER); 1219 if (cp == NULL) 1220 return explore_numeric(pai, hostname, servname, res, hostname); 1221 1222 /* 1223 * Handle special case of <scoped_address><delimiter><scope id> 1224 */ 1225 hostname2 = strdup(hostname); 1226 if (hostname2 == NULL) 1227 return EAI_MEMORY; 1228 /* terminate at the delimiter */ 1229 hostname2[cp - hostname] = '\0'; 1230 addr = hostname2; 1231 scope = cp + 1; 1232 1233 error = explore_numeric(pai, addr, servname, res, hostname); 1234 if (error == 0) { 1235 u_int32_t scopeid; 1236 1237 for (cur = *res; cur; cur = cur->ai_next) { 1238 if (cur->ai_family != AF_INET6) 1239 continue; 1240 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1241 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1242 free(hostname2); 1243 return(EAI_NONAME); /* XXX: is return OK? */ 1244 } 1245 sin6->sin6_scope_id = scopeid; 1246 } 1247 } 1248 1249 free(hostname2); 1250 1251 return error; 1252#endif 1253} 1254 1255static int 1256get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) 1257{ 1258 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1259 ai->ai_canonname = strdup(str); 1260 if (ai->ai_canonname == NULL) 1261 return EAI_MEMORY; 1262 } 1263 return 0; 1264} 1265 1266static struct addrinfo * 1267get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) 1268{ 1269 char *p; 1270 struct addrinfo *ai; 1271#ifdef FAITH 1272 struct in6_addr faith_prefix; 1273 char *fp_str; 1274 int translate = 0; 1275#endif 1276 1277#ifdef FAITH 1278 /* 1279 * Transfrom an IPv4 addr into a special IPv6 addr format for 1280 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1281 * 1282 * +-----------------------------------+------------+ 1283 * | faith prefix part (12 bytes) | embedded | 1284 * | | IPv4 addr part (4 bytes) 1285 * +-----------------------------------+------------+ 1286 * 1287 * faith prefix part is specified as ascii IPv6 addr format 1288 * in environmental variable GAI. 1289 * For FAITH to work correctly, routing to faith prefix must be 1290 * setup toward a machine where a FAITH daemon operates. 1291 * Also, the machine must enable some mechanizm 1292 * (e.g. faith interface hack) to divert those packet with 1293 * faith prefixed destination addr to user-land FAITH daemon. 1294 */ 1295 fp_str = getenv("GAI"); 1296 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1297 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1298 u_int32_t v4a; 1299 u_int8_t v4a_top; 1300 1301 memcpy(&v4a, addr, sizeof v4a); 1302 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1303 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1304 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1305 afd = &afdl[N_INET6]; 1306 memcpy(&faith_prefix.s6_addr[12], addr, 1307 sizeof(struct in_addr)); 1308 translate = 1; 1309 } 1310 } 1311#endif 1312 1313 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1314 + (afd->a_socklen)); 1315 if (ai == NULL) 1316 return NULL; 1317 1318 memcpy(ai, pai, sizeof(struct addrinfo)); 1319 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1320 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1321 ai->ai_addr->sa_len = afd->a_socklen; 1322 ai->ai_addrlen = afd->a_socklen; 1323 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1324 p = (char *)(void *)(ai->ai_addr); 1325#ifdef FAITH 1326 if (translate == 1) 1327 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1328 else 1329#endif 1330 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1331 return ai; 1332} 1333 1334static int 1335get_portmatch(const struct addrinfo *ai, const char *servname) 1336{ 1337 1338 /* get_port does not touch first argument when matchonly == 1. */ 1339 /* LINTED const cast */ 1340 return get_port((struct addrinfo *)ai, servname, 1); 1341} 1342 1343static int 1344get_port(struct addrinfo *ai, const char *servname, int matchonly) 1345{ 1346 const char *proto; 1347 struct servent *sp; 1348 int port; 1349 int allownumeric; 1350 1351 if (servname == NULL) 1352 return 0; 1353 switch (ai->ai_family) { 1354 case AF_INET: 1355#ifdef AF_INET6 1356 case AF_INET6: 1357#endif 1358 break; 1359 default: 1360 return 0; 1361 } 1362 1363 switch (ai->ai_socktype) { 1364 case SOCK_RAW: 1365 return EAI_SERVICE; 1366 case SOCK_DGRAM: 1367 case SOCK_STREAM: 1368 allownumeric = 1; 1369 break; 1370 case ANY: 1371 allownumeric = 0; 1372 break; 1373 default: 1374 return EAI_SOCKTYPE; 1375 } 1376 1377 port = str2number(servname); 1378 if (port >= 0) { 1379 if (!allownumeric) 1380 return EAI_SERVICE; 1381 if (port < 0 || port > 65535) 1382 return EAI_SERVICE; 1383 port = htons(port); 1384 } else { 1385 if (ai->ai_flags & AI_NUMERICSERV) 1386 return EAI_NONAME; 1387 switch (ai->ai_socktype) { 1388 case SOCK_DGRAM: 1389 proto = "udp"; 1390 break; 1391 case SOCK_STREAM: 1392 proto = "tcp"; 1393 break; 1394 default: 1395 proto = NULL; 1396 break; 1397 } 1398 1399 if ((sp = getservbyname(servname, proto)) == NULL) 1400 return EAI_SERVICE; 1401 port = sp->s_port; 1402 } 1403 1404 if (!matchonly) { 1405 switch (ai->ai_family) { 1406 case AF_INET: 1407 ((struct sockaddr_in *)(void *) 1408 ai->ai_addr)->sin_port = port; 1409 break; 1410#ifdef INET6 1411 case AF_INET6: 1412 ((struct sockaddr_in6 *)(void *) 1413 ai->ai_addr)->sin6_port = port; 1414 break; 1415#endif 1416 } 1417 } 1418 1419 return 0; 1420} 1421 1422static const struct afd * 1423find_afd(int af) 1424{ 1425 const struct afd *afd; 1426 1427 if (af == PF_UNSPEC) 1428 return NULL; 1429 for (afd = afdl; afd->a_af; afd++) { 1430 if (afd->a_af == af) 1431 return afd; 1432 } 1433 return NULL; 1434} 1435 1436/* 1437 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1438 * will take care of it. 1439 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1440 * if the code is right or not. 1441 * 1442 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1443 * _dns_getaddrinfo. 1444 */ 1445static int 1446addrconfig(struct addrinfo *pai) 1447{ 1448 int s, af; 1449 1450 /* 1451 * TODO: 1452 * Note that implementation dependent test for address 1453 * configuration should be done everytime called 1454 * (or apropriate interval), 1455 * because addresses will be dynamically assigned or deleted. 1456 */ 1457 af = pai->ai_family; 1458 if (af == AF_UNSPEC) { 1459 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1460 af = AF_INET; 1461 else { 1462 _close(s); 1463 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1464 af = AF_INET6; 1465 else 1466 _close(s); 1467 } 1468 } 1469 if (af != AF_UNSPEC) { 1470 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1471 return 0; 1472 _close(s); 1473 } 1474 pai->ai_family = af; 1475 return 1; 1476} 1477 1478#ifdef INET6 1479/* convert a string to a scope identifier. XXX: IPv6 specific */ 1480static int 1481ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid) 1482{ 1483 u_long lscopeid; 1484 struct in6_addr *a6; 1485 char *ep; 1486 1487 a6 = &sin6->sin6_addr; 1488 1489 /* empty scopeid portion is invalid */ 1490 if (*scope == '\0') 1491 return -1; 1492 1493 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1494 /* 1495 * We currently assume a one-to-one mapping between links 1496 * and interfaces, so we simply use interface indices for 1497 * like-local scopes. 1498 */ 1499 *scopeid = if_nametoindex(scope); 1500 if (*scopeid == 0) 1501 goto trynumeric; 1502 return 0; 1503 } 1504 1505 /* still unclear about literal, allow numeric only - placeholder */ 1506 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1507 goto trynumeric; 1508 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1509 goto trynumeric; 1510 else 1511 goto trynumeric; /* global */ 1512 1513 /* try to convert to a numeric id as a last resort */ 1514 trynumeric: 1515 errno = 0; 1516 lscopeid = strtoul(scope, &ep, 10); 1517 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1518 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1519 return 0; 1520 else 1521 return -1; 1522} 1523#endif 1524 1525 1526#ifdef NS_CACHING 1527static int 1528addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap, 1529 void *cache_mdata) 1530{ 1531 res_state statp; 1532 u_long res_options; 1533 1534 const int op_id = 0; /* identifies the getaddrinfo for the cache */ 1535 char *hostname; 1536 struct addrinfo *hints; 1537 1538 char *p; 1539 int ai_flags, ai_family, ai_socktype, ai_protocol; 1540 size_t desired_size, size; 1541 1542 statp = __res_state(); 1543 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES | 1544 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6); 1545 1546 hostname = va_arg(ap, char *); 1547 hints = va_arg(ap, struct addrinfo *); 1548 1549 desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4; 1550 if (hostname != NULL) { 1551 size = strlen(hostname); 1552 desired_size += size + 1; 1553 } else 1554 size = 0; 1555 1556 if (desired_size > *buffer_size) { 1557 *buffer_size = desired_size; 1558 return (NS_RETURN); 1559 } 1560 1561 if (hints == NULL) 1562 ai_flags = ai_family = ai_socktype = ai_protocol = 0; 1563 else { 1564 ai_flags = hints->ai_flags; 1565 ai_family = hints->ai_family; 1566 ai_socktype = hints->ai_socktype; 1567 ai_protocol = hints->ai_protocol; 1568 } 1569 1570 p = buffer; 1571 memcpy(p, &res_options, sizeof(res_options)); 1572 p += sizeof(res_options); 1573 1574 memcpy(p, &op_id, sizeof(int)); 1575 p += sizeof(int); 1576 1577 memcpy(p, &ai_flags, sizeof(int)); 1578 p += sizeof(int); 1579 1580 memcpy(p, &ai_family, sizeof(int)); 1581 p += sizeof(int); 1582 1583 memcpy(p, &ai_socktype, sizeof(int)); 1584 p += sizeof(int); 1585 1586 memcpy(p, &ai_protocol, sizeof(int)); 1587 p += sizeof(int); 1588 1589 if (hostname != NULL) 1590 memcpy(p, hostname, size); 1591 1592 *buffer_size = desired_size; 1593 return (NS_SUCCESS); 1594} 1595 1596static int 1597addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval, 1598 va_list ap, void *cache_mdata) 1599{ 1600 struct addrinfo *ai, *cai; 1601 char *p; 1602 size_t desired_size, size, ai_size; 1603 1604 ai = *((struct addrinfo **)retval); 1605 1606 desired_size = sizeof(size_t); 1607 ai_size = 0; 1608 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1609 desired_size += sizeof(struct addrinfo) + cai->ai_addrlen; 1610 if (cai->ai_canonname != NULL) 1611 desired_size += sizeof(size_t) + 1612 strlen(cai->ai_canonname); 1613 ++ai_size; 1614 } 1615 1616 if (desired_size > *buffer_size) { 1617 /* this assignment is here for future use */ 1618 errno = ERANGE; 1619 *buffer_size = desired_size; 1620 return (NS_RETURN); 1621 } 1622 1623 memset(buffer, 0, desired_size); 1624 p = buffer; 1625 1626 memcpy(p, &ai_size, sizeof(size_t)); 1627 p += sizeof(size_t); 1628 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1629 memcpy(p, cai, sizeof(struct addrinfo)); 1630 p += sizeof(struct addrinfo); 1631 1632 memcpy(p, cai->ai_addr, cai->ai_addrlen); 1633 p += cai->ai_addrlen; 1634 1635 if (cai->ai_canonname != NULL) { 1636 size = strlen(cai->ai_canonname); 1637 memcpy(p, &size, sizeof(size_t)); 1638 p += sizeof(size_t); 1639 1640 memcpy(p, cai->ai_canonname, size); 1641 p += size; 1642 } 1643 } 1644 1645 return (NS_SUCCESS); 1646} 1647 1648static int 1649addrinfo_unmarshal_func(char *buffer, size_t buffer_size, void *retval, 1650 va_list ap, void *cache_mdata) 1651{ 1652 struct addrinfo new_ai, *result, *sentinel, *lasts; 1653 1654 char *p; 1655 size_t ai_size, ai_i, size; 1656 1657 p = buffer; 1658 memcpy(&ai_size, p, sizeof(size_t)); 1659 p += sizeof(size_t); 1660 1661 result = NULL; 1662 lasts = NULL; 1663 for (ai_i = 0; ai_i < ai_size; ++ai_i) { 1664 memcpy(&new_ai, p, sizeof(struct addrinfo)); 1665 p += sizeof(struct addrinfo); 1666 size = new_ai.ai_addrlen + sizeof(struct addrinfo) + 1667 _ALIGNBYTES; 1668 1669 sentinel = (struct addrinfo *)malloc(size); 1670 memset(sentinel, 0, size); 1671 1672 memcpy(sentinel, &new_ai, sizeof(struct addrinfo)); 1673 sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel + 1674 sizeof(struct addrinfo)); 1675 1676 memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen); 1677 p += new_ai.ai_addrlen; 1678 1679 if (new_ai.ai_canonname != NULL) { 1680 memcpy(&size, p, sizeof(size_t)); 1681 p += sizeof(size_t); 1682 1683 sentinel->ai_canonname = (char *)malloc(size + 1); 1684 memset(sentinel->ai_canonname, 0, size + 1); 1685 1686 memcpy(sentinel->ai_canonname, p, size); 1687 p += size; 1688 } 1689 1690 if (result == NULL) { 1691 result = sentinel; 1692 lasts = sentinel; 1693 } else { 1694 lasts->ai_next = sentinel; 1695 lasts = sentinel; 1696 } 1697 } 1698 1699 *((struct addrinfo **)retval) = result; 1700 return (NS_SUCCESS); 1701} 1702#endif /* NS_CACHING */ 1703 1704/* 1705 * FQDN hostname, DNS lookup 1706 */ 1707static int 1708explore_fqdn(const struct addrinfo *pai, const char *hostname, 1709 const char *servname, struct addrinfo **res) 1710{ 1711 struct addrinfo *result; 1712 struct addrinfo *cur; 1713 int error = 0; 1714 1715#ifdef NS_CACHING 1716 static const nss_cache_info cache_info = 1717 NS_COMMON_CACHE_INFO_INITIALIZER( 1718 hosts, NULL, addrinfo_id_func, addrinfo_marshal_func, 1719 addrinfo_unmarshal_func); 1720#endif 1721 static const ns_dtab dtab[] = { 1722 NS_FILES_CB(_files_getaddrinfo, NULL) 1723 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1724 NS_NIS_CB(_yp_getaddrinfo, NULL) 1725#ifdef NS_CACHING 1726 NS_CACHE_CB(&cache_info) 1727#endif 1728 { 0 } 1729 }; 1730 1731 result = NULL; 1732 1733 /* 1734 * if the servname does not match socktype/protocol, ignore it. 1735 */ 1736 if (get_portmatch(pai, servname) != 0) 1737 return 0; 1738 1739 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1740 default_dns_files, hostname, pai)) { 1741 case NS_TRYAGAIN: 1742 error = EAI_AGAIN; 1743 goto free; 1744 case NS_UNAVAIL: 1745 error = EAI_FAIL; 1746 goto free; 1747 case NS_NOTFOUND: 1748 error = EAI_NONAME; 1749 goto free; 1750 case NS_SUCCESS: 1751 error = 0; 1752 for (cur = result; cur; cur = cur->ai_next) { 1753 GET_PORT(cur, servname); 1754 /* canonname should be filled already */ 1755 } 1756 break; 1757 } 1758 1759 *res = result; 1760 1761 return 0; 1762 1763free: 1764 if (result) 1765 freeaddrinfo(result); 1766 return error; 1767} 1768 1769#ifdef DEBUG 1770static const char AskedForGot[] = 1771 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1772#endif 1773 1774static struct addrinfo * 1775getanswer(const querybuf *answer, int anslen, const char *qname, int qtype, 1776 const struct addrinfo *pai, res_state res) 1777{ 1778 struct addrinfo sentinel, *cur; 1779 struct addrinfo ai; 1780 const struct afd *afd; 1781 char *canonname; 1782 const HEADER *hp; 1783 const u_char *cp; 1784 int n; 1785 const u_char *eom; 1786 char *bp, *ep; 1787 int type, class, ancount, qdcount; 1788 int haveanswer, had_error; 1789 char tbuf[MAXDNAME]; 1790 int (*name_ok)(const char *); 1791 char hostbuf[8*1024]; 1792 1793 memset(&sentinel, 0, sizeof(sentinel)); 1794 cur = &sentinel; 1795 1796 canonname = NULL; 1797 eom = answer->buf + anslen; 1798 switch (qtype) { 1799 case T_A: 1800 case T_AAAA: 1801 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1802 name_ok = res_hnok; 1803 break; 1804 default: 1805 return (NULL); /* XXX should be abort(); */ 1806 } 1807 /* 1808 * find first satisfactory answer 1809 */ 1810 hp = &answer->hdr; 1811 ancount = ntohs(hp->ancount); 1812 qdcount = ntohs(hp->qdcount); 1813 bp = hostbuf; 1814 ep = hostbuf + sizeof hostbuf; 1815 cp = answer->buf + HFIXEDSZ; 1816 if (qdcount != 1) { 1817 RES_SET_H_ERRNO(res, NO_RECOVERY); 1818 return (NULL); 1819 } 1820 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1821 if ((n < 0) || !(*name_ok)(bp)) { 1822 RES_SET_H_ERRNO(res, NO_RECOVERY); 1823 return (NULL); 1824 } 1825 cp += n + QFIXEDSZ; 1826 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1827 /* res_send() has already verified that the query name is the 1828 * same as the one we sent; this just gets the expanded name 1829 * (i.e., with the succeeding search-domain tacked on). 1830 */ 1831 n = strlen(bp) + 1; /* for the \0 */ 1832 if (n >= MAXHOSTNAMELEN) { 1833 RES_SET_H_ERRNO(res, NO_RECOVERY); 1834 return (NULL); 1835 } 1836 canonname = bp; 1837 bp += n; 1838 /* The qname can be abbreviated, but h_name is now absolute. */ 1839 qname = canonname; 1840 } 1841 haveanswer = 0; 1842 had_error = 0; 1843 while (ancount-- > 0 && cp < eom && !had_error) { 1844 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1845 if ((n < 0) || !(*name_ok)(bp)) { 1846 had_error++; 1847 continue; 1848 } 1849 cp += n; /* name */ 1850 type = _getshort(cp); 1851 cp += INT16SZ; /* type */ 1852 class = _getshort(cp); 1853 cp += INT16SZ + INT32SZ; /* class, TTL */ 1854 n = _getshort(cp); 1855 cp += INT16SZ; /* len */ 1856 if (class != C_IN) { 1857 /* XXX - debug? syslog? */ 1858 cp += n; 1859 continue; /* XXX - had_error++ ? */ 1860 } 1861 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1862 type == T_CNAME) { 1863 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1864 if ((n < 0) || !(*name_ok)(tbuf)) { 1865 had_error++; 1866 continue; 1867 } 1868 cp += n; 1869 /* Get canonical name. */ 1870 n = strlen(tbuf) + 1; /* for the \0 */ 1871 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1872 had_error++; 1873 continue; 1874 } 1875 strlcpy(bp, tbuf, ep - bp); 1876 canonname = bp; 1877 bp += n; 1878 continue; 1879 } 1880 if (qtype == T_ANY) { 1881 if (!(type == T_A || type == T_AAAA)) { 1882 cp += n; 1883 continue; 1884 } 1885 } else if (type != qtype) { 1886#ifdef DEBUG 1887 if (type != T_KEY && type != T_SIG) 1888 syslog(LOG_NOTICE|LOG_AUTH, 1889 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1890 qname, p_class(C_IN), p_type(qtype), 1891 p_type(type)); 1892#endif 1893 cp += n; 1894 continue; /* XXX - had_error++ ? */ 1895 } 1896 switch (type) { 1897 case T_A: 1898 case T_AAAA: 1899 if (strcasecmp(canonname, bp) != 0) { 1900#ifdef DEBUG 1901 syslog(LOG_NOTICE|LOG_AUTH, 1902 AskedForGot, canonname, bp); 1903#endif 1904 cp += n; 1905 continue; /* XXX - had_error++ ? */ 1906 } 1907 if (type == T_A && n != INADDRSZ) { 1908 cp += n; 1909 continue; 1910 } 1911 if (type == T_AAAA && n != IN6ADDRSZ) { 1912 cp += n; 1913 continue; 1914 } 1915#ifdef FILTER_V4MAPPED 1916 if (type == T_AAAA) { 1917 struct in6_addr in6; 1918 memcpy(&in6, cp, sizeof(in6)); 1919 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1920 cp += n; 1921 continue; 1922 } 1923 } 1924#endif 1925 if (!haveanswer) { 1926 int nn; 1927 1928 canonname = bp; 1929 nn = strlen(bp) + 1; /* for the \0 */ 1930 bp += nn; 1931 } 1932 1933 /* don't overwrite pai */ 1934 ai = *pai; 1935 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1936 afd = find_afd(ai.ai_family); 1937 if (afd == NULL) { 1938 cp += n; 1939 continue; 1940 } 1941 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1942 if (cur->ai_next == NULL) 1943 had_error++; 1944 while (cur && cur->ai_next) 1945 cur = cur->ai_next; 1946 cp += n; 1947 break; 1948 default: 1949 abort(); 1950 } 1951 if (!had_error) 1952 haveanswer++; 1953 } 1954 if (haveanswer) { 1955#if defined(RESOLVSORT) 1956 /* 1957 * We support only IPv4 address for backward 1958 * compatibility against gethostbyname(3). 1959 */ 1960 if (res->nsort && qtype == T_A) { 1961 if (addr4sort(&sentinel, res) < 0) { 1962 freeaddrinfo(sentinel.ai_next); 1963 RES_SET_H_ERRNO(res, NO_RECOVERY); 1964 return NULL; 1965 } 1966 } 1967#endif /*RESOLVSORT*/ 1968 if (!canonname) 1969 (void)get_canonname(pai, sentinel.ai_next, qname); 1970 else 1971 (void)get_canonname(pai, sentinel.ai_next, canonname); 1972 RES_SET_H_ERRNO(res, NETDB_SUCCESS); 1973 return sentinel.ai_next; 1974 } 1975 1976 RES_SET_H_ERRNO(res, NO_RECOVERY); 1977 return NULL; 1978} 1979 1980#ifdef RESOLVSORT 1981struct addr_ptr { 1982 struct addrinfo *ai; 1983 int aval; 1984}; 1985 1986static int 1987addr4sort(struct addrinfo *sentinel, res_state res) 1988{ 1989 struct addrinfo *ai; 1990 struct addr_ptr *addrs, addr; 1991 struct sockaddr_in *sin; 1992 int naddrs, i, j; 1993 int needsort = 0; 1994 1995 if (!sentinel) 1996 return -1; 1997 naddrs = 0; 1998 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1999 naddrs++; 2000 if (naddrs < 2) 2001 return 0; /* We don't need sorting. */ 2002 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 2003 return -1; 2004 i = 0; 2005 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 2006 sin = (struct sockaddr_in *)ai->ai_addr; 2007 for (j = 0; (unsigned)j < res->nsort; j++) { 2008 if (res->sort_list[j].addr.s_addr == 2009 (sin->sin_addr.s_addr & res->sort_list[j].mask)) 2010 break; 2011 } 2012 addrs[i].ai = ai; 2013 addrs[i].aval = j; 2014 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 2015 needsort = i; 2016 i++; 2017 } 2018 if (!needsort) { 2019 free(addrs); 2020 return 0; 2021 } 2022 2023 while (needsort < naddrs) { 2024 for (j = needsort - 1; j >= 0; j--) { 2025 if (addrs[j].aval > addrs[j+1].aval) { 2026 addr = addrs[j]; 2027 addrs[j] = addrs[j + 1]; 2028 addrs[j + 1] = addr; 2029 } else 2030 break; 2031 } 2032 needsort++; 2033 } 2034 2035 ai = sentinel; 2036 for (i = 0; i < naddrs; ++i) { 2037 ai->ai_next = addrs[i].ai; 2038 ai = ai->ai_next; 2039 } 2040 ai->ai_next = NULL; 2041 free(addrs); 2042 return 0; 2043} 2044#endif /*RESOLVSORT*/ 2045 2046/*ARGSUSED*/ 2047static int 2048_dns_getaddrinfo(void *rv, void *cb_data, va_list ap) 2049{ 2050 struct addrinfo *ai; 2051 querybuf *buf, *buf2; 2052 const char *hostname; 2053 const struct addrinfo *pai; 2054 struct addrinfo sentinel, *cur; 2055 struct res_target q, q2; 2056 res_state res; 2057 2058 hostname = va_arg(ap, char *); 2059 pai = va_arg(ap, const struct addrinfo *); 2060 2061 memset(&q, 0, sizeof(q)); 2062 memset(&q2, 0, sizeof(q2)); 2063 memset(&sentinel, 0, sizeof(sentinel)); 2064 cur = &sentinel; 2065 2066 buf = malloc(sizeof(*buf)); 2067 if (!buf) { 2068 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2069 return NS_NOTFOUND; 2070 } 2071 buf2 = malloc(sizeof(*buf2)); 2072 if (!buf2) { 2073 free(buf); 2074 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2075 return NS_NOTFOUND; 2076 } 2077 2078 switch (pai->ai_family) { 2079 case AF_UNSPEC: 2080 q.name = hostname; 2081 q.qclass = C_IN; 2082 q.qtype = T_A; 2083 q.answer = buf->buf; 2084 q.anslen = sizeof(buf->buf); 2085 q.next = &q2; 2086 q2.name = hostname; 2087 q2.qclass = C_IN; 2088 q2.qtype = T_AAAA; 2089 q2.answer = buf2->buf; 2090 q2.anslen = sizeof(buf2->buf); 2091 break; 2092 case AF_INET: 2093 q.name = hostname; 2094 q.qclass = C_IN; 2095 q.qtype = T_A; 2096 q.answer = buf->buf; 2097 q.anslen = sizeof(buf->buf); 2098 break; 2099 case AF_INET6: 2100 q.name = hostname; 2101 q.qclass = C_IN; 2102 q.qtype = T_AAAA; 2103 q.answer = buf->buf; 2104 q.anslen = sizeof(buf->buf); 2105 break; 2106 default: 2107 free(buf); 2108 free(buf2); 2109 return NS_UNAVAIL; 2110 } 2111 2112 res = __res_state(); 2113 if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) { 2114 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2115 free(buf); 2116 free(buf2); 2117 return NS_NOTFOUND; 2118 } 2119 2120 if (res_searchN(hostname, &q, res) < 0) { 2121 free(buf); 2122 free(buf2); 2123 return NS_NOTFOUND; 2124 } 2125 /* prefer IPv6 */ 2126 if (q.next) { 2127 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res); 2128 if (ai) { 2129 cur->ai_next = ai; 2130 while (cur && cur->ai_next) 2131 cur = cur->ai_next; 2132 } 2133 } 2134 ai = getanswer(buf, q.n, q.name, q.qtype, pai, res); 2135 if (ai) 2136 cur->ai_next = ai; 2137 free(buf); 2138 free(buf2); 2139 if (sentinel.ai_next == NULL) 2140 switch (res->res_h_errno) { 2141 case HOST_NOT_FOUND: 2142 return NS_NOTFOUND; 2143 case TRY_AGAIN: 2144 return NS_TRYAGAIN; 2145 default: 2146 return NS_UNAVAIL; 2147 } 2148 *((struct addrinfo **)rv) = sentinel.ai_next; 2149 return NS_SUCCESS; 2150} 2151 2152static void 2153_sethtent(FILE **hostf) 2154{ 2155 if (!*hostf) 2156 *hostf = fopen(_PATH_HOSTS, "r"); 2157 else 2158 rewind(*hostf); 2159} 2160 2161static void 2162_endhtent(FILE **hostf) 2163{ 2164 if (*hostf) { 2165 (void) fclose(*hostf); 2166 *hostf = NULL; 2167 } 2168} 2169 2170static struct addrinfo * 2171_gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2172{ 2173 char *p; 2174 char *cp, *tname, *cname; 2175 struct addrinfo hints, *res0, *res; 2176 int error; 2177 const char *addr; 2178 char hostbuf[8*1024]; 2179 2180 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "r"))) 2181 return (NULL); 2182again: 2183 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 2184 return (NULL); 2185 if (*p == '#') 2186 goto again; 2187 cp = strpbrk(p, "#\n"); 2188 if (cp != NULL) 2189 *cp = '\0'; 2190 if (!(cp = strpbrk(p, " \t"))) 2191 goto again; 2192 *cp++ = '\0'; 2193 addr = p; 2194 cname = NULL; 2195 /* if this is not something we're looking for, skip it. */ 2196 while (cp && *cp) { 2197 if (*cp == ' ' || *cp == '\t') { 2198 cp++; 2199 continue; 2200 } 2201 tname = cp; 2202 if (cname == NULL) 2203 cname = cp; 2204 if ((cp = strpbrk(cp, " \t")) != NULL) 2205 *cp++ = '\0'; 2206 if (strcasecmp(name, tname) == 0) 2207 goto found; 2208 } 2209 goto again; 2210 2211found: 2212 /* we should not glob socktype/protocol here */ 2213 memset(&hints, 0, sizeof(hints)); 2214 hints.ai_family = pai->ai_family; 2215 hints.ai_socktype = SOCK_DGRAM; 2216 hints.ai_protocol = 0; 2217 hints.ai_flags = AI_NUMERICHOST; 2218 error = getaddrinfo(addr, "0", &hints, &res0); 2219 if (error) 2220 goto again; 2221#ifdef FILTER_V4MAPPED 2222 /* XXX should check all items in the chain */ 2223 if (res0->ai_family == AF_INET6 && 2224 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2225 freeaddrinfo(res0); 2226 goto again; 2227 } 2228#endif 2229 for (res = res0; res; res = res->ai_next) { 2230 /* cover it up */ 2231 res->ai_flags = pai->ai_flags; 2232 res->ai_socktype = pai->ai_socktype; 2233 res->ai_protocol = pai->ai_protocol; 2234 2235 if (pai->ai_flags & AI_CANONNAME) { 2236 if (get_canonname(pai, res, cname) != 0) { 2237 freeaddrinfo(res0); 2238 goto again; 2239 } 2240 } 2241 } 2242 return res0; 2243} 2244 2245/*ARGSUSED*/ 2246static int 2247_files_getaddrinfo(void *rv, void *cb_data, va_list ap) 2248{ 2249 const char *name; 2250 const struct addrinfo *pai; 2251 struct addrinfo sentinel, *cur; 2252 struct addrinfo *p; 2253 FILE *hostf = NULL; 2254 2255 name = va_arg(ap, char *); 2256 pai = va_arg(ap, struct addrinfo *); 2257 2258 memset(&sentinel, 0, sizeof(sentinel)); 2259 cur = &sentinel; 2260 2261 _sethtent(&hostf); 2262 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2263 cur->ai_next = p; 2264 while (cur && cur->ai_next) 2265 cur = cur->ai_next; 2266 } 2267 _endhtent(&hostf); 2268 2269 *((struct addrinfo **)rv) = sentinel.ai_next; 2270 if (sentinel.ai_next == NULL) 2271 return NS_NOTFOUND; 2272 return NS_SUCCESS; 2273} 2274 2275#ifdef YP 2276/*ARGSUSED*/ 2277static struct addrinfo * 2278_yphostent(char *line, const struct addrinfo *pai) 2279{ 2280 struct addrinfo sentinel, *cur; 2281 struct addrinfo hints, *res, *res0; 2282 int error; 2283 char *p = line; 2284 const char *addr, *canonname; 2285 char *nextline; 2286 char *cp; 2287 2288 addr = canonname = NULL; 2289 2290 memset(&sentinel, 0, sizeof(sentinel)); 2291 cur = &sentinel; 2292 2293nextline: 2294 /* terminate line */ 2295 cp = strchr(p, '\n'); 2296 if (cp) { 2297 *cp++ = '\0'; 2298 nextline = cp; 2299 } else 2300 nextline = NULL; 2301 2302 cp = strpbrk(p, " \t"); 2303 if (cp == NULL) { 2304 if (canonname == NULL) 2305 return (NULL); 2306 else 2307 goto done; 2308 } 2309 *cp++ = '\0'; 2310 2311 addr = p; 2312 2313 while (cp && *cp) { 2314 if (*cp == ' ' || *cp == '\t') { 2315 cp++; 2316 continue; 2317 } 2318 if (!canonname) 2319 canonname = cp; 2320 if ((cp = strpbrk(cp, " \t")) != NULL) 2321 *cp++ = '\0'; 2322 } 2323 2324 hints = *pai; 2325 hints.ai_flags = AI_NUMERICHOST; 2326 error = getaddrinfo(addr, NULL, &hints, &res0); 2327 if (error == 0) { 2328 for (res = res0; res; res = res->ai_next) { 2329 /* cover it up */ 2330 res->ai_flags = pai->ai_flags; 2331 2332 if (pai->ai_flags & AI_CANONNAME) 2333 (void)get_canonname(pai, res, canonname); 2334 } 2335 } else 2336 res0 = NULL; 2337 if (res0) { 2338 cur->ai_next = res0; 2339 while (cur && cur->ai_next) 2340 cur = cur->ai_next; 2341 } 2342 2343 if (nextline) { 2344 p = nextline; 2345 goto nextline; 2346 } 2347 2348done: 2349 return sentinel.ai_next; 2350} 2351 2352/*ARGSUSED*/ 2353static int 2354_yp_getaddrinfo(void *rv, void *cb_data, va_list ap) 2355{ 2356 struct addrinfo sentinel, *cur; 2357 struct addrinfo *ai = NULL; 2358 char *ypbuf; 2359 int ypbuflen, r; 2360 const char *name; 2361 const struct addrinfo *pai; 2362 char *ypdomain; 2363 2364 if (_yp_check(&ypdomain) == 0) 2365 return NS_UNAVAIL; 2366 2367 name = va_arg(ap, char *); 2368 pai = va_arg(ap, const struct addrinfo *); 2369 2370 memset(&sentinel, 0, sizeof(sentinel)); 2371 cur = &sentinel; 2372 2373 /* hosts.byname is only for IPv4 (Solaris8) */ 2374 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2375 r = yp_match(ypdomain, "hosts.byname", name, 2376 (int)strlen(name), &ypbuf, &ypbuflen); 2377 if (r == 0) { 2378 struct addrinfo ai4; 2379 2380 ai4 = *pai; 2381 ai4.ai_family = AF_INET; 2382 ai = _yphostent(ypbuf, &ai4); 2383 if (ai) { 2384 cur->ai_next = ai; 2385 while (cur && cur->ai_next) 2386 cur = cur->ai_next; 2387 } 2388 free(ypbuf); 2389 } 2390 } 2391 2392 /* ipnodes.byname can hold both IPv4/v6 */ 2393 r = yp_match(ypdomain, "ipnodes.byname", name, 2394 (int)strlen(name), &ypbuf, &ypbuflen); 2395 if (r == 0) { 2396 ai = _yphostent(ypbuf, pai); 2397 if (ai) 2398 cur->ai_next = ai; 2399 free(ypbuf); 2400 } 2401 2402 if (sentinel.ai_next == NULL) { 2403 RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND); 2404 return NS_NOTFOUND; 2405 } 2406 *((struct addrinfo **)rv) = sentinel.ai_next; 2407 return NS_SUCCESS; 2408} 2409#endif 2410 2411/* resolver logic */ 2412 2413/* 2414 * Formulate a normal query, send, and await answer. 2415 * Returned answer is placed in supplied buffer "answer". 2416 * Perform preliminary check of answer, returning success only 2417 * if no error is indicated and the answer count is nonzero. 2418 * Return the size of the response on success, -1 on error. 2419 * Error number is left in h_errno. 2420 * 2421 * Caller must parse answer and determine whether it answers the question. 2422 */ 2423static int 2424res_queryN(const char *name, struct res_target *target, res_state res) 2425{ 2426 u_char *buf; 2427 HEADER *hp; 2428 int n; 2429 u_int oflags; 2430 struct res_target *t; 2431 int rcode; 2432 int ancount; 2433 2434 rcode = NOERROR; 2435 ancount = 0; 2436 2437 buf = malloc(MAXPACKET); 2438 if (!buf) { 2439 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2440 return -1; 2441 } 2442 2443 for (t = target; t; t = t->next) { 2444 int class, type; 2445 u_char *answer; 2446 int anslen; 2447 2448 hp = (HEADER *)(void *)t->answer; 2449 2450 /* make it easier... */ 2451 class = t->qclass; 2452 type = t->qtype; 2453 answer = t->answer; 2454 anslen = t->anslen; 2455 2456 oflags = res->_flags; 2457 2458again: 2459 hp->rcode = NOERROR; /* default */ 2460 2461#ifdef DEBUG 2462 if (res->options & RES_DEBUG) 2463 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2464#endif 2465 2466 n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL, 2467 buf, MAXPACKET); 2468 if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 && 2469 (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U) 2470 n = res_nopt(res, n, buf, MAXPACKET, anslen); 2471 if (n <= 0) { 2472#ifdef DEBUG 2473 if (res->options & RES_DEBUG) 2474 printf(";; res_query: mkquery failed\n"); 2475#endif 2476 free(buf); 2477 RES_SET_H_ERRNO(res, NO_RECOVERY); 2478 return (n); 2479 } 2480 n = res_nsend(res, buf, n, answer, anslen); 2481 if (n < 0) { 2482 /* 2483 * if the query choked with EDNS0, retry 2484 * without EDNS0 2485 */ 2486 if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) 2487 != 0U && 2488 ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) { 2489 res->_flags |= RES_F_EDNS0ERR; 2490 if (res->options & RES_DEBUG) 2491 printf(";; res_nquery: retry without EDNS0\n"); 2492 goto again; 2493 } 2494 rcode = hp->rcode; /* record most recent error */ 2495#ifdef DEBUG 2496 if (res->options & RES_DEBUG) 2497 printf(";; res_query: send error\n"); 2498#endif 2499 continue; 2500 } 2501 2502 if (n > anslen) 2503 hp->rcode = FORMERR; /* XXX not very informative */ 2504 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2505 rcode = hp->rcode; /* record most recent error */ 2506#ifdef DEBUG 2507 if (res->options & RES_DEBUG) 2508 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2509 ntohs(hp->ancount)); 2510#endif 2511 continue; 2512 } 2513 2514 ancount += ntohs(hp->ancount); 2515 2516 t->n = n; 2517 } 2518 2519 free(buf); 2520 2521 if (ancount == 0) { 2522 switch (rcode) { 2523 case NXDOMAIN: 2524 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); 2525 break; 2526 case SERVFAIL: 2527 RES_SET_H_ERRNO(res, TRY_AGAIN); 2528 break; 2529 case NOERROR: 2530 RES_SET_H_ERRNO(res, NO_DATA); 2531 break; 2532 case FORMERR: 2533 case NOTIMP: 2534 case REFUSED: 2535 default: 2536 RES_SET_H_ERRNO(res, NO_RECOVERY); 2537 break; 2538 } 2539 return (-1); 2540 } 2541 return (ancount); 2542} 2543 2544/* 2545 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2546 * Return the size of the response on success, -1 on error. 2547 * If enabled, implement search rules until answer or unrecoverable failure 2548 * is detected. Error code, if any, is left in h_errno. 2549 */ 2550static int 2551res_searchN(const char *name, struct res_target *target, res_state res) 2552{ 2553 const char *cp, * const *domain; 2554 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2555 u_int dots; 2556 int trailing_dot, ret, saved_herrno; 2557 int got_nodata = 0, got_servfail = 0, root_on_list = 0; 2558 int tried_as_is = 0; 2559 int searched = 0; 2560 char abuf[MAXDNAME]; 2561 2562 errno = 0; 2563 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */ 2564 dots = 0; 2565 for (cp = name; *cp; cp++) 2566 dots += (*cp == '.'); 2567 trailing_dot = 0; 2568 if (cp > name && *--cp == '.') 2569 trailing_dot++; 2570 2571 /* 2572 * if there aren't any dots, it could be a user-level alias 2573 */ 2574 if (!dots && 2575 (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL) 2576 return (res_queryN(cp, target, res)); 2577 2578 /* 2579 * If there are enough dots in the name, let's just give it a 2580 * try 'as is'. The threshold can be set with the "ndots" option. 2581 * Also, query 'as is', if there is a trailing dot in the name. 2582 */ 2583 saved_herrno = -1; 2584 if (dots >= res->ndots || trailing_dot) { 2585 ret = res_querydomainN(name, NULL, target, res); 2586 if (ret > 0 || trailing_dot) 2587 return (ret); 2588 if (errno == ECONNREFUSED) { 2589 RES_SET_H_ERRNO(res, TRY_AGAIN); 2590 return (-1); 2591 } 2592 switch (res->res_h_errno) { 2593 case NO_DATA: 2594 case HOST_NOT_FOUND: 2595 break; 2596 case TRY_AGAIN: 2597 if (hp->rcode == SERVFAIL) 2598 break; 2599 /* FALLTHROUGH */ 2600 default: 2601 return (-1); 2602 } 2603 saved_herrno = res->res_h_errno; 2604 tried_as_is++; 2605 } 2606 2607 /* 2608 * We do at least one level of search if 2609 * - there is no dot and RES_DEFNAME is set, or 2610 * - there is at least one dot, there is no trailing dot, 2611 * and RES_DNSRCH is set. 2612 */ 2613 if ((!dots && (res->options & RES_DEFNAMES)) || 2614 (dots && !trailing_dot && (res->options & RES_DNSRCH))) { 2615 int done = 0; 2616 2617 for (domain = (const char * const *)res->dnsrch; 2618 *domain && !done; 2619 domain++) { 2620 searched = 1; 2621 2622 if (domain[0][0] == '\0' || 2623 (domain[0][0] == '.' && domain[0][1] == '\0')) 2624 root_on_list++; 2625 2626 if (root_on_list && tried_as_is) 2627 continue; 2628 2629 ret = res_querydomainN(name, *domain, target, res); 2630 if (ret > 0) 2631 return (ret); 2632 2633 /* 2634 * If no server present, give up. 2635 * If name isn't found in this domain, 2636 * keep trying higher domains in the search list 2637 * (if that's enabled). 2638 * On a NO_DATA error, keep trying, otherwise 2639 * a wildcard entry of another type could keep us 2640 * from finding this entry higher in the domain. 2641 * If we get some other error (negative answer or 2642 * server failure), then stop searching up, 2643 * but try the input name below in case it's 2644 * fully-qualified. 2645 */ 2646 if (errno == ECONNREFUSED) { 2647 RES_SET_H_ERRNO(res, TRY_AGAIN); 2648 return (-1); 2649 } 2650 2651 switch (res->res_h_errno) { 2652 case NO_DATA: 2653 got_nodata++; 2654 /* FALLTHROUGH */ 2655 case HOST_NOT_FOUND: 2656 /* keep trying */ 2657 break; 2658 case TRY_AGAIN: 2659 got_servfail++; 2660 if (hp->rcode == SERVFAIL) { 2661 /* try next search element, if any */ 2662 break; 2663 } 2664 /* FALLTHROUGH */ 2665 default: 2666 /* anything else implies that we're done */ 2667 done++; 2668 } 2669 /* 2670 * if we got here for some reason other than DNSRCH, 2671 * we only wanted one iteration of the loop, so stop. 2672 */ 2673 if (!(res->options & RES_DNSRCH)) 2674 done++; 2675 } 2676 } 2677 2678 switch (res->res_h_errno) { 2679 case NO_DATA: 2680 case HOST_NOT_FOUND: 2681 break; 2682 case TRY_AGAIN: 2683 if (hp->rcode == SERVFAIL) 2684 break; 2685 /* FALLTHROUGH */ 2686 default: 2687 goto giveup; 2688 } 2689 2690 /* 2691 * If the query has not already been tried as is then try it 2692 * unless RES_NOTLDQUERY is set and there were no dots. 2693 */ 2694 if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) && 2695 !(tried_as_is || root_on_list)) { 2696 ret = res_querydomainN(name, NULL, target, res); 2697 if (ret > 0) 2698 return (ret); 2699 } 2700 2701 /* 2702 * if we got here, we didn't satisfy the search. 2703 * if we did an initial full query, return that query's h_errno 2704 * (note that we wouldn't be here if that query had succeeded). 2705 * else if we ever got a nodata, send that back as the reason. 2706 * else send back meaningless h_errno, that being the one from 2707 * the last DNSRCH we did. 2708 */ 2709giveup: 2710 if (saved_herrno != -1) 2711 RES_SET_H_ERRNO(res, saved_herrno); 2712 else if (got_nodata) 2713 RES_SET_H_ERRNO(res, NO_DATA); 2714 else if (got_servfail) 2715 RES_SET_H_ERRNO(res, TRY_AGAIN); 2716 return (-1); 2717} 2718 2719/* 2720 * Perform a call on res_query on the concatenation of name and domain, 2721 * removing a trailing dot from name if domain is NULL. 2722 */ 2723static int 2724res_querydomainN(const char *name, const char *domain, 2725 struct res_target *target, res_state res) 2726{ 2727 char nbuf[MAXDNAME]; 2728 const char *longname = nbuf; 2729 size_t n, d; 2730 2731#ifdef DEBUG 2732 if (res->options & RES_DEBUG) 2733 printf(";; res_querydomain(%s, %s)\n", 2734 name, domain?domain:"<Nil>"); 2735#endif 2736 if (domain == NULL) { 2737 /* 2738 * Check for trailing '.'; 2739 * copy without '.' if present. 2740 */ 2741 n = strlen(name); 2742 if (n >= MAXDNAME) { 2743 RES_SET_H_ERRNO(res, NO_RECOVERY); 2744 return (-1); 2745 } 2746 if (n > 0 && name[--n] == '.') { 2747 strncpy(nbuf, name, n); 2748 nbuf[n] = '\0'; 2749 } else 2750 longname = name; 2751 } else { 2752 n = strlen(name); 2753 d = strlen(domain); 2754 if (n + d + 1 >= MAXDNAME) { 2755 RES_SET_H_ERRNO(res, NO_RECOVERY); 2756 return (-1); 2757 } 2758 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2759 } 2760 return (res_queryN(longname, target, res)); 2761} 2762