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 * Issues to be discussed: 34 * - Return values. There are nonstandard return values defined and used 35 * in the source code. This is because RFC2553 is silent about which error 36 * code must be returned for which situation. 37 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 38 * invalid. current code - SEGV on freeaddrinfo(NULL) 39 * 40 * Note: 41 * - The code filters out AFs that are not supported by the kernel, 42 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 43 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 44 * in ai_flags? 45 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 46 * (1) what should we do against numeric hostname (2) what should we do 47 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 48 * non-loopback address configured? global address configured? 49 * 50 * OS specific notes for freebsd4: 51 * - FreeBSD supported $GAI. The code does not. 52 */ 53 54 #include <sys/cdefs.h> 55 __FBSDID("$FreeBSD$"); 56 57 #include "namespace.h" 58 #include <sys/types.h> 59 #include <sys/param.h> 60 #include <sys/socket.h> 61 #include <net/if.h> 62 #include <netinet/in.h> 63 #include <net/if_types.h> 64 #include <ifaddrs.h> 65 #include <sys/queue.h> 66 #ifdef INET6 67 #include <net/if_var.h> 68 #include <sys/sysctl.h> 69 #include <sys/ioctl.h> 70 #include <netinet6/in6_var.h> 71 #include <netinet6/nd6.h> 72 #endif 73 #include <arpa/inet.h> 74 #include <arpa/nameser.h> 75 #include <rpc/rpc.h> 76 #include <rpcsvc/yp_prot.h> 77 #include <rpcsvc/ypclnt.h> 78 #include <netdb.h> 79 #include <resolv.h> 80 #include <string.h> 81 #include <stdlib.h> 82 #include <stddef.h> 83 #include <ctype.h> 84 #include <unistd.h> 85 #include <stdio.h> 86 #include <errno.h> 87 88 #include "res_config.h" 89 90 #ifdef DEBUG 91 #include <syslog.h> 92 #endif 93 94 #include <stdarg.h> 95 #include <nsswitch.h> 96 #include "un-namespace.h" 97 #include "libc_private.h" 98 #ifdef NS_CACHING 99 #include "nscache.h" 100 #endif 101 102 #define ANY 0 103 #define YES 1 104 #define NO 0 105 106 static const char in_addrany[] = { 0, 0, 0, 0 }; 107 static const char in_loopback[] = { 127, 0, 0, 1 }; 108 #ifdef INET6 109 static const char in6_addrany[] = { 110 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 111 }; 112 static const char in6_loopback[] = { 113 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 114 }; 115 #endif 116 117 struct policyqueue { 118 TAILQ_ENTRY(policyqueue) pc_entry; 119 #ifdef INET6 120 struct in6_addrpolicy pc_policy; 121 #endif 122 }; 123 TAILQ_HEAD(policyhead, policyqueue); 124 125 static const struct afd { 126 int a_af; 127 int a_addrlen; 128 socklen_t a_socklen; 129 int a_off; 130 const char *a_addrany; 131 const char *a_loopback; 132 int a_scoped; 133 } afdl [] = { 134 #ifdef INET6 135 #define N_INET6 0 136 {PF_INET6, sizeof(struct in6_addr), 137 sizeof(struct sockaddr_in6), 138 offsetof(struct sockaddr_in6, sin6_addr), 139 in6_addrany, in6_loopback, 1}, 140 #define N_INET 1 141 #else 142 #define N_INET 0 143 #endif 144 {PF_INET, sizeof(struct in_addr), 145 sizeof(struct sockaddr_in), 146 offsetof(struct sockaddr_in, sin_addr), 147 in_addrany, in_loopback, 0}, 148 {0, 0, 0, 0, NULL, NULL, 0}, 149 }; 150 151 struct explore { 152 int e_af; 153 int e_socktype; 154 int e_protocol; 155 int e_wild; 156 #define WILD_AF(ex) ((ex)->e_wild & 0x01) 157 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 158 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 159 }; 160 161 static const struct explore explore[] = { 162 #if 0 163 { PF_LOCAL, ANY, ANY, 0x01 }, 164 #endif 165 #ifdef INET6 166 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, 0x07 }, 167 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, 0x07 }, 168 { PF_INET6, SOCK_STREAM, IPPROTO_SCTP, 0x03 }, 169 { PF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 }, 170 { PF_INET6, SOCK_DGRAM, IPPROTO_UDPLITE, 0x03 }, 171 { PF_INET6, SOCK_RAW, ANY, 0x05 }, 172 #endif 173 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, 0x07 }, 174 { PF_INET, SOCK_STREAM, IPPROTO_TCP, 0x07 }, 175 { PF_INET, SOCK_STREAM, IPPROTO_SCTP, 0x03 }, 176 { PF_INET, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 }, 177 { PF_INET, SOCK_DGRAM, IPPROTO_UDPLITE, 0x03 }, 178 { PF_INET, SOCK_RAW, ANY, 0x05 }, 179 { -1, 0, 0, 0 }, 180 }; 181 182 #ifdef INET6 183 #define PTON_MAX 16 184 #else 185 #define PTON_MAX 4 186 #endif 187 188 #define AIO_SRCFLAG_DEPRECATED 0x1 189 190 struct ai_order { 191 union { 192 struct sockaddr_storage aiou_ss; 193 struct sockaddr aiou_sa; 194 } aio_src_un; 195 #define aio_srcsa aio_src_un.aiou_sa 196 u_int32_t aio_srcflag; 197 int aio_srcscope; 198 int aio_dstscope; 199 struct policyqueue *aio_srcpolicy; 200 struct policyqueue *aio_dstpolicy; 201 struct addrinfo *aio_ai; 202 int aio_matchlen; 203 }; 204 205 static const ns_src default_dns_files[] = { 206 { NSSRC_FILES, NS_SUCCESS }, 207 { NSSRC_DNS, NS_SUCCESS }, 208 { 0 } 209 }; 210 211 struct res_target { 212 struct res_target *next; 213 const char *name; /* domain name */ 214 int qclass, qtype; /* class and type of query */ 215 u_char *answer; /* buffer to put answer */ 216 int anslen; /* size of answer buffer */ 217 int n; /* result length */ 218 }; 219 220 #define MAXPACKET (64*1024) 221 222 typedef union { 223 HEADER hdr; 224 u_char buf[MAXPACKET]; 225 } querybuf; 226 227 static int str2number(const char *, int *); 228 static int explore_copy(const struct addrinfo *, const struct addrinfo *, 229 struct addrinfo **); 230 static int explore_null(const struct addrinfo *, 231 const char *, struct addrinfo **); 232 static int explore_numeric(const struct addrinfo *, const char *, 233 const char *, struct addrinfo **, const char *); 234 static int explore_numeric_scope(const struct addrinfo *, const char *, 235 const char *, struct addrinfo **); 236 static int get_canonname(const struct addrinfo *, 237 struct addrinfo *, const char *); 238 static struct addrinfo *get_ai(const struct addrinfo *, 239 const struct afd *, const char *); 240 static struct addrinfo *copy_ai(const struct addrinfo *); 241 static int get_portmatch(const struct addrinfo *, const char *); 242 static int get_port(struct addrinfo *, const char *, int); 243 static const struct afd *find_afd(int); 244 static int addrconfig(struct addrinfo *); 245 #ifdef INET6 246 static int is_ifdisabled(char *); 247 #endif 248 static void set_source(struct ai_order *, struct policyhead *); 249 static int comp_dst(const void *, const void *); 250 #ifdef INET6 251 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 252 #endif 253 static int gai_addr2scopetype(struct sockaddr *); 254 255 static int explore_fqdn(const struct addrinfo *, const char *, 256 const char *, struct addrinfo **); 257 258 static int reorder(struct addrinfo *); 259 static int get_addrselectpolicy(struct policyhead *); 260 static void free_addrselectpolicy(struct policyhead *); 261 static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 262 struct policyhead *); 263 static int matchlen(struct sockaddr *, struct sockaddr *); 264 265 static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 266 const struct addrinfo *, res_state); 267 #if defined(RESOLVSORT) 268 static int addr4sort(struct addrinfo *, res_state); 269 #endif 270 static int _dns_getaddrinfo(void *, void *, va_list); 271 static void _sethtent(FILE **); 272 static void _endhtent(FILE **); 273 static struct addrinfo *_gethtent(FILE **, const char *, 274 const struct addrinfo *); 275 static int _files_getaddrinfo(void *, void *, va_list); 276 #ifdef YP 277 static struct addrinfo *_yphostent(char *, const struct addrinfo *); 278 static int _yp_getaddrinfo(void *, void *, va_list); 279 #endif 280 #ifdef NS_CACHING 281 static int addrinfo_id_func(char *, size_t *, va_list, void *); 282 static int addrinfo_marshal_func(char *, size_t *, void *, va_list, void *); 283 static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, void *); 284 #endif 285 286 static int res_queryN(const char *, struct res_target *, res_state); 287 static int res_searchN(const char *, struct res_target *, res_state); 288 static int res_querydomainN(const char *, const char *, 289 struct res_target *, res_state); 290 291 /* XXX macros that make external reference is BAD. */ 292 293 #define GET_AI(ai, afd, addr) \ 294 do { \ 295 /* external reference: pai, error, and label free */ \ 296 (ai) = get_ai(pai, (afd), (addr)); \ 297 if ((ai) == NULL) { \ 298 error = EAI_MEMORY; \ 299 goto free; \ 300 } \ 301 } while (/*CONSTCOND*/0) 302 303 #define GET_PORT(ai, serv) \ 304 do { \ 305 /* external reference: error and label free */ \ 306 error = get_port((ai), (serv), 0); \ 307 if (error != 0) \ 308 goto free; \ 309 } while (/*CONSTCOND*/0) 310 311 #define GET_CANONNAME(ai, str) \ 312 do { \ 313 /* external reference: pai, error and label free */ \ 314 error = get_canonname(pai, (ai), (str)); \ 315 if (error != 0) \ 316 goto free; \ 317 } while (/*CONSTCOND*/0) 318 319 #define ERR(err) \ 320 do { \ 321 /* external reference: error, and label bad */ \ 322 error = (err); \ 323 goto bad; \ 324 /*NOTREACHED*/ \ 325 } while (/*CONSTCOND*/0) 326 327 #define MATCH_FAMILY(x, y, w) \ 328 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 329 #define MATCH(x, y, w) \ 330 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 331 332 void 333 freeaddrinfo(struct addrinfo *ai) 334 { 335 struct addrinfo *next; 336 337 do { 338 next = ai->ai_next; 339 if (ai->ai_canonname) 340 free(ai->ai_canonname); 341 /* no need to free(ai->ai_addr) */ 342 free(ai); 343 ai = next; 344 } while (ai); 345 } 346 347 static int 348 str2number(const char *p, int *portp) 349 { 350 char *ep; 351 unsigned long v; 352 353 if (*p == '\0') 354 return -1; 355 ep = NULL; 356 errno = 0; 357 v = strtoul(p, &ep, 10); 358 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) { 359 *portp = v; 360 return 0; 361 } else 362 return -1; 363 } 364 365 int 366 getaddrinfo(const char *hostname, const char *servname, 367 const struct addrinfo *hints, struct addrinfo **res) 368 { 369 struct addrinfo sentinel; 370 struct addrinfo *cur; 371 int error = 0; 372 struct addrinfo ai, ai0, *afai; 373 struct addrinfo *pai; 374 const struct afd *afd; 375 const struct explore *ex; 376 struct addrinfo *afailist[sizeof(afdl)/sizeof(afdl[0])]; 377 struct addrinfo *afai_unspec; 378 int found; 379 int numeric = 0; 380 381 /* ensure we return NULL on errors */ 382 *res = NULL; 383 384 memset(&ai, 0, sizeof(ai)); 385 386 memset(afailist, 0, sizeof(afailist)); 387 afai_unspec = NULL; 388 389 memset(&sentinel, 0, sizeof(sentinel)); 390 cur = &sentinel; 391 pai = &ai; 392 pai->ai_flags = 0; 393 pai->ai_family = PF_UNSPEC; 394 pai->ai_socktype = ANY; 395 pai->ai_protocol = ANY; 396 pai->ai_addrlen = 0; 397 pai->ai_canonname = NULL; 398 pai->ai_addr = NULL; 399 pai->ai_next = NULL; 400 401 if (hostname == NULL && servname == NULL) 402 return EAI_NONAME; 403 if (hints) { 404 /* error check for hints */ 405 if (hints->ai_addrlen || hints->ai_canonname || 406 hints->ai_addr || hints->ai_next) 407 ERR(EAI_BADHINTS); /* xxx */ 408 if (hints->ai_flags & ~AI_MASK) 409 ERR(EAI_BADFLAGS); 410 switch (hints->ai_family) { 411 case PF_UNSPEC: 412 case PF_INET: 413 #ifdef INET6 414 case PF_INET6: 415 #endif 416 break; 417 default: 418 ERR(EAI_FAMILY); 419 } 420 memcpy(pai, hints, sizeof(*pai)); 421 422 /* 423 * if both socktype/protocol are specified, check if they 424 * are meaningful combination. 425 */ 426 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 427 for (ex = explore; ex->e_af >= 0; ex++) { 428 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, 429 WILD_AF(ex))) 430 continue; 431 if (!MATCH(pai->ai_socktype, ex->e_socktype, 432 WILD_SOCKTYPE(ex))) 433 continue; 434 if (!MATCH(pai->ai_protocol, ex->e_protocol, 435 WILD_PROTOCOL(ex))) 436 continue; 437 438 /* matched */ 439 break; 440 } 441 442 if (ex->e_af < 0) 443 ERR(EAI_BADHINTS); 444 } 445 } 446 447 /* 448 * check for special cases. (1) numeric servname is disallowed if 449 * socktype/protocol are left unspecified. (2) servname is disallowed 450 * for raw and other inet{,6} sockets. 451 */ 452 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 453 #ifdef PF_INET6 454 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 455 #endif 456 ) { 457 ai0 = *pai; /* backup *pai */ 458 459 if (pai->ai_family == PF_UNSPEC) { 460 #ifdef PF_INET6 461 pai->ai_family = PF_INET6; 462 #else 463 pai->ai_family = PF_INET; 464 #endif 465 } 466 error = get_portmatch(pai, servname); 467 if (error) 468 goto bad; 469 470 *pai = ai0; 471 } 472 473 ai0 = *pai; 474 475 /* 476 * NULL hostname, or numeric hostname. 477 * If numeric representation of AF1 can be interpreted as FQDN 478 * representation of AF2, we need to think again about the code below. 479 */ 480 found = 0; 481 for (afd = afdl; afd->a_af; afd++) { 482 *pai = ai0; 483 484 if (!MATCH_FAMILY(pai->ai_family, afd->a_af, 1)) 485 continue; 486 487 if (pai->ai_family == PF_UNSPEC) 488 pai->ai_family = afd->a_af; 489 490 if (hostname == NULL) { 491 error = explore_null(pai, servname, 492 &afailist[afd - afdl]); 493 494 /* 495 * Errors from explore_null should be unexpected and 496 * be caught to avoid returning an incomplete result. 497 */ 498 if (error != 0) 499 goto bad; 500 } else { 501 error = explore_numeric_scope(pai, hostname, servname, 502 &afailist[afd - afdl]); 503 504 /* 505 * explore_numeric_scope returns an error for address 506 * families that do not match that of hostname. 507 * Thus we should not catch the error at this moment. 508 */ 509 } 510 511 if (!error && afailist[afd - afdl]) 512 found++; 513 } 514 if (found) { 515 numeric = 1; 516 goto globcopy; 517 } 518 519 if (hostname == NULL) 520 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 521 if (pai->ai_flags & AI_NUMERICHOST) 522 ERR(EAI_NONAME); 523 524 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 525 ERR(EAI_FAIL); 526 527 /* 528 * hostname as alphabetical name. 529 */ 530 *pai = ai0; 531 error = explore_fqdn(pai, hostname, servname, &afai_unspec); 532 533 globcopy: 534 for (ex = explore; ex->e_af >= 0; ex++) { 535 *pai = ai0; 536 537 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 538 continue; 539 if (!MATCH(pai->ai_socktype, ex->e_socktype, 540 WILD_SOCKTYPE(ex))) 541 continue; 542 if (!MATCH(pai->ai_protocol, ex->e_protocol, 543 WILD_PROTOCOL(ex))) 544 continue; 545 546 if (pai->ai_family == PF_UNSPEC) 547 pai->ai_family = ex->e_af; 548 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 549 pai->ai_socktype = ex->e_socktype; 550 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 551 pai->ai_protocol = ex->e_protocol; 552 553 /* 554 * if the servname does not match socktype/protocol, ignore it. 555 */ 556 if (get_portmatch(pai, servname) != 0) 557 continue; 558 559 if (afai_unspec) 560 afai = afai_unspec; 561 else { 562 if ((afd = find_afd(pai->ai_family)) == NULL) 563 continue; 564 /* XXX assumes that afd points inside afdl[] */ 565 afai = afailist[afd - afdl]; 566 } 567 if (!afai) 568 continue; 569 570 error = explore_copy(pai, afai, &cur->ai_next); 571 if (error != 0) 572 goto bad; 573 574 while (cur && cur->ai_next) 575 cur = cur->ai_next; 576 } 577 578 /* 579 * ensure we return either: 580 * - error == 0, non-NULL *res 581 * - error != 0, NULL *res 582 */ 583 if (error == 0) { 584 if (sentinel.ai_next) { 585 /* 586 * If the returned entry is for an active connection, 587 * and the given name is not numeric, reorder the 588 * list, so that the application would try the list 589 * in the most efficient order. Since the head entry 590 * of the original list may contain ai_canonname and 591 * that entry may be moved elsewhere in the new list, 592 * we keep the pointer and will restore it in the new 593 * head entry. (Note that RFC3493 requires the head 594 * entry store it when requested by the caller). 595 */ 596 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 597 if (!numeric) { 598 char *canonname; 599 600 canonname = 601 sentinel.ai_next->ai_canonname; 602 sentinel.ai_next->ai_canonname = NULL; 603 (void)reorder(&sentinel); 604 if (sentinel.ai_next->ai_canonname == 605 NULL) { 606 sentinel.ai_next->ai_canonname 607 = canonname; 608 } else if (canonname != NULL) 609 free(canonname); 610 } 611 } 612 *res = sentinel.ai_next; 613 } else 614 error = EAI_FAIL; 615 } 616 617 bad: 618 if (afai_unspec) 619 freeaddrinfo(afai_unspec); 620 for (afd = afdl; afd->a_af; afd++) { 621 if (afailist[afd - afdl]) 622 freeaddrinfo(afailist[afd - afdl]); 623 } 624 if (!*res) 625 if (sentinel.ai_next) 626 freeaddrinfo(sentinel.ai_next); 627 628 return (error); 629 } 630 631 static int 632 reorder(struct addrinfo *sentinel) 633 { 634 struct addrinfo *ai, **aip; 635 struct ai_order *aio; 636 int i, n; 637 struct policyhead policyhead; 638 639 /* count the number of addrinfo elements for sorting. */ 640 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 641 ; 642 643 /* 644 * If the number is small enough, we can skip the reordering process. 645 */ 646 if (n <= 1) 647 return(n); 648 649 /* allocate a temporary array for sort and initialization of it. */ 650 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 651 return(n); /* give up reordering */ 652 memset(aio, 0, sizeof(*aio) * n); 653 654 /* retrieve address selection policy from the kernel */ 655 TAILQ_INIT(&policyhead); 656 if (!get_addrselectpolicy(&policyhead)) { 657 /* no policy is installed into kernel, we don't sort. */ 658 free(aio); 659 return (n); 660 } 661 662 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 663 aio[i].aio_ai = ai; 664 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 665 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 666 &policyhead); 667 set_source(&aio[i], &policyhead); 668 } 669 670 /* perform sorting. */ 671 qsort(aio, n, sizeof(*aio), comp_dst); 672 673 /* reorder the addrinfo chain. */ 674 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 675 *aip = aio[i].aio_ai; 676 aip = &aio[i].aio_ai->ai_next; 677 } 678 *aip = NULL; 679 680 /* cleanup and return */ 681 free(aio); 682 free_addrselectpolicy(&policyhead); 683 return(n); 684 } 685 686 static int 687 get_addrselectpolicy(struct policyhead *head) 688 { 689 #ifdef INET6 690 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 691 size_t l; 692 char *buf; 693 struct in6_addrpolicy *pol, *ep; 694 695 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 696 return (0); 697 if (l == 0) 698 return (0); 699 if ((buf = malloc(l)) == NULL) 700 return (0); 701 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 702 free(buf); 703 return (0); 704 } 705 706 ep = (struct in6_addrpolicy *)(buf + l); 707 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 708 struct policyqueue *new; 709 710 if ((new = malloc(sizeof(*new))) == NULL) { 711 free_addrselectpolicy(head); /* make the list empty */ 712 break; 713 } 714 new->pc_policy = *pol; 715 TAILQ_INSERT_TAIL(head, new, pc_entry); 716 } 717 718 free(buf); 719 return (1); 720 #else 721 return (0); 722 #endif 723 } 724 725 static void 726 free_addrselectpolicy(struct policyhead *head) 727 { 728 struct policyqueue *ent, *nent; 729 730 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 731 nent = TAILQ_NEXT(ent, pc_entry); 732 TAILQ_REMOVE(head, ent, pc_entry); 733 free(ent); 734 } 735 } 736 737 static struct policyqueue * 738 match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 739 { 740 #ifdef INET6 741 struct policyqueue *ent, *bestent = NULL; 742 struct in6_addrpolicy *pol; 743 int matchlen, bestmatchlen = -1; 744 u_char *mp, *ep, *k, *p, m; 745 struct sockaddr_in6 key; 746 747 switch(addr->sa_family) { 748 case AF_INET6: 749 key = *(struct sockaddr_in6 *)addr; 750 break; 751 case AF_INET: 752 /* convert the address into IPv4-mapped IPv6 address. */ 753 memset(&key, 0, sizeof(key)); 754 key.sin6_family = AF_INET6; 755 key.sin6_len = sizeof(key); 756 key.sin6_addr.s6_addr[10] = 0xff; 757 key.sin6_addr.s6_addr[11] = 0xff; 758 memcpy(&key.sin6_addr.s6_addr[12], 759 &((struct sockaddr_in *)addr)->sin_addr, 4); 760 break; 761 default: 762 return(NULL); 763 } 764 765 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 766 pol = &ent->pc_policy; 767 matchlen = 0; 768 769 mp = (u_char *)&pol->addrmask.sin6_addr; 770 ep = mp + 16; /* XXX: scope field? */ 771 k = (u_char *)&key.sin6_addr; 772 p = (u_char *)&pol->addr.sin6_addr; 773 for (; mp < ep && *mp; mp++, k++, p++) { 774 m = *mp; 775 if ((*k & m) != *p) 776 goto next; /* not match */ 777 if (m == 0xff) /* short cut for a typical case */ 778 matchlen += 8; 779 else { 780 while (m >= 0x80) { 781 matchlen++; 782 m <<= 1; 783 } 784 } 785 } 786 787 /* matched. check if this is better than the current best. */ 788 if (matchlen > bestmatchlen) { 789 bestent = ent; 790 bestmatchlen = matchlen; 791 } 792 793 next: 794 continue; 795 } 796 797 return(bestent); 798 #else 799 return(NULL); 800 #endif 801 802 } 803 804 static void 805 set_source(struct ai_order *aio, struct policyhead *ph) 806 { 807 struct addrinfo ai = *aio->aio_ai; 808 struct sockaddr_storage ss; 809 socklen_t srclen; 810 int s; 811 812 /* set unspec ("no source is available"), just in case */ 813 aio->aio_srcsa.sa_family = AF_UNSPEC; 814 aio->aio_srcscope = -1; 815 816 switch(ai.ai_family) { 817 case AF_INET: 818 #ifdef INET6 819 case AF_INET6: 820 #endif 821 break; 822 default: /* ignore unsupported AFs explicitly */ 823 return; 824 } 825 826 /* XXX: make a dummy addrinfo to call connect() */ 827 ai.ai_socktype = SOCK_DGRAM; 828 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 829 ai.ai_next = NULL; 830 memset(&ss, 0, sizeof(ss)); 831 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 832 ai.ai_addr = (struct sockaddr *)&ss; 833 get_port(&ai, "1", 0); 834 835 /* open a socket to get the source address for the given dst */ 836 if ((s = _socket(ai.ai_family, ai.ai_socktype | SOCK_CLOEXEC, 837 ai.ai_protocol)) < 0) 838 return; /* give up */ 839 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 840 goto cleanup; 841 srclen = ai.ai_addrlen; 842 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 843 aio->aio_srcsa.sa_family = AF_UNSPEC; 844 goto cleanup; 845 } 846 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 847 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 848 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 849 #ifdef INET6 850 if (ai.ai_family == AF_INET6) { 851 struct in6_ifreq ifr6; 852 u_int32_t flags6; 853 854 memset(&ifr6, 0, sizeof(ifr6)); 855 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 856 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 857 flags6 = ifr6.ifr_ifru.ifru_flags6; 858 if ((flags6 & IN6_IFF_DEPRECATED)) 859 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 860 } 861 } 862 #endif 863 864 cleanup: 865 _close(s); 866 return; 867 } 868 869 static int 870 matchlen(struct sockaddr *src, struct sockaddr *dst) 871 { 872 int match = 0; 873 u_char *s, *d; 874 u_char *lim, r; 875 int addrlen; 876 877 switch (src->sa_family) { 878 #ifdef INET6 879 case AF_INET6: 880 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 881 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 882 addrlen = sizeof(struct in6_addr); 883 lim = s + addrlen; 884 break; 885 #endif 886 case AF_INET: 887 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; 888 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; 889 addrlen = sizeof(struct in_addr); 890 lim = s + addrlen; 891 break; 892 default: 893 return(0); 894 } 895 896 while (s < lim) 897 if ((r = (*d++ ^ *s++)) != 0) { 898 while (r < addrlen * 8) { 899 match++; 900 r <<= 1; 901 } 902 break; 903 } else 904 match += 8; 905 return(match); 906 } 907 908 static int 909 comp_dst(const void *arg1, const void *arg2) 910 { 911 const struct ai_order *dst1 = arg1, *dst2 = arg2; 912 913 /* 914 * Rule 1: Avoid unusable destinations. 915 * XXX: we currently do not consider if an appropriate route exists. 916 */ 917 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 918 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 919 return(-1); 920 } 921 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 922 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 923 return(1); 924 } 925 926 /* Rule 2: Prefer matching scope. */ 927 if (dst1->aio_dstscope == dst1->aio_srcscope && 928 dst2->aio_dstscope != dst2->aio_srcscope) { 929 return(-1); 930 } 931 if (dst1->aio_dstscope != dst1->aio_srcscope && 932 dst2->aio_dstscope == dst2->aio_srcscope) { 933 return(1); 934 } 935 936 /* Rule 3: Avoid deprecated addresses. */ 937 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 938 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 939 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 940 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 941 return(-1); 942 } 943 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 944 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 945 return(1); 946 } 947 } 948 949 /* Rule 4: Prefer home addresses. */ 950 /* XXX: not implemented yet */ 951 952 /* Rule 5: Prefer matching label. */ 953 #ifdef INET6 954 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 955 dst1->aio_srcpolicy->pc_policy.label == 956 dst1->aio_dstpolicy->pc_policy.label && 957 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 958 dst2->aio_srcpolicy->pc_policy.label != 959 dst2->aio_dstpolicy->pc_policy.label)) { 960 return(-1); 961 } 962 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 963 dst2->aio_srcpolicy->pc_policy.label == 964 dst2->aio_dstpolicy->pc_policy.label && 965 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 966 dst1->aio_srcpolicy->pc_policy.label != 967 dst1->aio_dstpolicy->pc_policy.label)) { 968 return(1); 969 } 970 #endif 971 972 /* Rule 6: Prefer higher precedence. */ 973 #ifdef INET6 974 if (dst1->aio_dstpolicy && 975 (dst2->aio_dstpolicy == NULL || 976 dst1->aio_dstpolicy->pc_policy.preced > 977 dst2->aio_dstpolicy->pc_policy.preced)) { 978 return(-1); 979 } 980 if (dst2->aio_dstpolicy && 981 (dst1->aio_dstpolicy == NULL || 982 dst2->aio_dstpolicy->pc_policy.preced > 983 dst1->aio_dstpolicy->pc_policy.preced)) { 984 return(1); 985 } 986 #endif 987 988 /* Rule 7: Prefer native transport. */ 989 /* XXX: not implemented yet */ 990 991 /* Rule 8: Prefer smaller scope. */ 992 if (dst1->aio_dstscope >= 0 && 993 dst1->aio_dstscope < dst2->aio_dstscope) { 994 return(-1); 995 } 996 if (dst2->aio_dstscope >= 0 && 997 dst2->aio_dstscope < dst1->aio_dstscope) { 998 return(1); 999 } 1000 1001 /* 1002 * Rule 9: Use longest matching prefix. 1003 * We compare the match length in a same AF only. 1004 */ 1005 if (dst1->aio_ai->ai_addr->sa_family == 1006 dst2->aio_ai->ai_addr->sa_family && 1007 dst1->aio_ai->ai_addr->sa_family != AF_INET) { 1008 if (dst1->aio_matchlen > dst2->aio_matchlen) { 1009 return(-1); 1010 } 1011 if (dst1->aio_matchlen < dst2->aio_matchlen) { 1012 return(1); 1013 } 1014 } 1015 1016 /* Rule 10: Otherwise, leave the order unchanged. */ 1017 return(-1); 1018 } 1019 1020 /* 1021 * Copy from scope.c. 1022 * XXX: we should standardize the functions and link them as standard 1023 * library. 1024 */ 1025 static int 1026 gai_addr2scopetype(struct sockaddr *sa) 1027 { 1028 #ifdef INET6 1029 struct sockaddr_in6 *sa6; 1030 #endif 1031 struct sockaddr_in *sa4; 1032 1033 switch(sa->sa_family) { 1034 #ifdef INET6 1035 case AF_INET6: 1036 sa6 = (struct sockaddr_in6 *)sa; 1037 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1038 /* just use the scope field of the multicast address */ 1039 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1040 } 1041 /* 1042 * Unicast addresses: map scope type to corresponding scope 1043 * value defined for multcast addresses. 1044 * XXX: hardcoded scope type values are bad... 1045 */ 1046 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1047 return(1); /* node local scope */ 1048 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1049 return(2); /* link-local scope */ 1050 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1051 return(5); /* site-local scope */ 1052 return(14); /* global scope */ 1053 break; 1054 #endif 1055 case AF_INET: 1056 /* 1057 * IPv4 pseudo scoping according to RFC 3484. 1058 */ 1059 sa4 = (struct sockaddr_in *)sa; 1060 /* IPv4 autoconfiguration addresses have link-local scope. */ 1061 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1062 ((u_char *)&sa4->sin_addr)[1] == 254) 1063 return(2); 1064 /* Private addresses have site-local scope. */ 1065 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1066 (((u_char *)&sa4->sin_addr)[0] == 172 && 1067 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1068 (((u_char *)&sa4->sin_addr)[0] == 192 && 1069 ((u_char *)&sa4->sin_addr)[1] == 168)) 1070 return(14); /* XXX: It should be 5 unless NAT */ 1071 /* Loopback addresses have link-local scope. */ 1072 if (((u_char *)&sa4->sin_addr)[0] == 127) 1073 return(2); 1074 return(14); 1075 break; 1076 default: 1077 errno = EAFNOSUPPORT; /* is this a good error? */ 1078 return(-1); 1079 } 1080 } 1081 1082 static int 1083 explore_copy(const struct addrinfo *pai, const struct addrinfo *src0, 1084 struct addrinfo **res) 1085 { 1086 int error; 1087 struct addrinfo sentinel, *cur; 1088 const struct addrinfo *src; 1089 1090 error = 0; 1091 sentinel.ai_next = NULL; 1092 cur = &sentinel; 1093 1094 for (src = src0; src != NULL; src = src->ai_next) { 1095 if (src->ai_family != pai->ai_family) 1096 continue; 1097 1098 cur->ai_next = copy_ai(src); 1099 if (!cur->ai_next) { 1100 error = EAI_MEMORY; 1101 goto fail; 1102 } 1103 1104 cur->ai_next->ai_socktype = pai->ai_socktype; 1105 cur->ai_next->ai_protocol = pai->ai_protocol; 1106 cur = cur->ai_next; 1107 } 1108 1109 *res = sentinel.ai_next; 1110 return 0; 1111 1112 fail: 1113 freeaddrinfo(sentinel.ai_next); 1114 return error; 1115 } 1116 1117 /* 1118 * hostname == NULL. 1119 * passive socket -> anyaddr (0.0.0.0 or ::) 1120 * non-passive socket -> localhost (127.0.0.1 or ::1) 1121 */ 1122 static int 1123 explore_null(const struct addrinfo *pai, const char *servname, 1124 struct addrinfo **res) 1125 { 1126 int s; 1127 const struct afd *afd; 1128 struct addrinfo *ai; 1129 int error; 1130 1131 *res = NULL; 1132 ai = NULL; 1133 1134 /* 1135 * filter out AFs that are not supported by the kernel 1136 * XXX errno? 1137 */ 1138 s = _socket(pai->ai_family, SOCK_DGRAM | SOCK_CLOEXEC, 0); 1139 if (s < 0) { 1140 if (errno != EMFILE) 1141 return 0; 1142 } else 1143 _close(s); 1144 1145 afd = find_afd(pai->ai_family); 1146 if (afd == NULL) 1147 return 0; 1148 1149 if (pai->ai_flags & AI_PASSIVE) { 1150 GET_AI(ai, afd, afd->a_addrany); 1151 GET_PORT(ai, servname); 1152 } else { 1153 GET_AI(ai, afd, afd->a_loopback); 1154 GET_PORT(ai, servname); 1155 } 1156 1157 *res = ai; 1158 return 0; 1159 1160 free: 1161 if (ai != NULL) 1162 freeaddrinfo(ai); 1163 return error; 1164 } 1165 1166 /* 1167 * numeric hostname 1168 */ 1169 static int 1170 explore_numeric(const struct addrinfo *pai, const char *hostname, 1171 const char *servname, struct addrinfo **res, const char *canonname) 1172 { 1173 const struct afd *afd; 1174 struct addrinfo *ai; 1175 int error; 1176 char pton[PTON_MAX]; 1177 1178 *res = NULL; 1179 ai = NULL; 1180 1181 afd = find_afd(pai->ai_family); 1182 if (afd == NULL) 1183 return 0; 1184 1185 switch (afd->a_af) { 1186 case AF_INET: 1187 /* 1188 * RFC3493 requires getaddrinfo() to accept AF_INET formats 1189 * that are accepted by inet_addr() and its family. The 1190 * accepted forms includes the "classful" one, which inet_pton 1191 * does not accept. So we need to separate the case for 1192 * AF_INET. 1193 */ 1194 if (inet_aton(hostname, (struct in_addr *)pton) != 1) 1195 return 0; 1196 break; 1197 default: 1198 if (inet_pton(afd->a_af, hostname, pton) != 1) 1199 return 0; 1200 break; 1201 } 1202 1203 if (pai->ai_family == afd->a_af) { 1204 GET_AI(ai, afd, pton); 1205 GET_PORT(ai, servname); 1206 if ((pai->ai_flags & AI_CANONNAME)) { 1207 /* 1208 * Set the numeric address itself as the canonical 1209 * name, based on a clarification in RFC3493. 1210 */ 1211 GET_CANONNAME(ai, canonname); 1212 } 1213 } else { 1214 /* 1215 * XXX: This should not happen since we already matched the AF 1216 * by find_afd. 1217 */ 1218 ERR(EAI_FAMILY); 1219 } 1220 1221 *res = ai; 1222 return 0; 1223 1224 free: 1225 bad: 1226 if (ai != NULL) 1227 freeaddrinfo(ai); 1228 return error; 1229 } 1230 1231 /* 1232 * numeric hostname with scope 1233 */ 1234 static int 1235 explore_numeric_scope(const struct addrinfo *pai, const char *hostname, 1236 const char *servname, struct addrinfo **res) 1237 { 1238 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 1239 return explore_numeric(pai, hostname, servname, res, hostname); 1240 #else 1241 const struct afd *afd; 1242 struct addrinfo *cur; 1243 int error; 1244 char *cp, *hostname2 = NULL, *scope, *addr; 1245 struct sockaddr_in6 *sin6; 1246 1247 afd = find_afd(pai->ai_family); 1248 if (afd == NULL) 1249 return 0; 1250 1251 if (!afd->a_scoped) 1252 return explore_numeric(pai, hostname, servname, res, hostname); 1253 1254 cp = strchr(hostname, SCOPE_DELIMITER); 1255 if (cp == NULL) 1256 return explore_numeric(pai, hostname, servname, res, hostname); 1257 1258 /* 1259 * Handle special case of <scoped_address><delimiter><scope id> 1260 */ 1261 hostname2 = strdup(hostname); 1262 if (hostname2 == NULL) 1263 return EAI_MEMORY; 1264 /* terminate at the delimiter */ 1265 hostname2[cp - hostname] = '\0'; 1266 addr = hostname2; 1267 scope = cp + 1; 1268 1269 error = explore_numeric(pai, addr, servname, res, hostname); 1270 if (error == 0) { 1271 u_int32_t scopeid; 1272 1273 for (cur = *res; cur; cur = cur->ai_next) { 1274 if (cur->ai_family != AF_INET6) 1275 continue; 1276 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1277 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1278 free(hostname2); 1279 freeaddrinfo(*res); 1280 *res = NULL; 1281 return(EAI_NONAME); /* XXX: is return OK? */ 1282 } 1283 sin6->sin6_scope_id = scopeid; 1284 } 1285 } 1286 1287 free(hostname2); 1288 1289 if (error && *res) { 1290 freeaddrinfo(*res); 1291 *res = NULL; 1292 } 1293 return error; 1294 #endif 1295 } 1296 1297 static int 1298 get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) 1299 { 1300 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1301 ai->ai_canonname = strdup(str); 1302 if (ai->ai_canonname == NULL) 1303 return EAI_MEMORY; 1304 } 1305 return 0; 1306 } 1307 1308 static struct addrinfo * 1309 get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) 1310 { 1311 char *p; 1312 struct addrinfo *ai; 1313 1314 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1315 + (afd->a_socklen)); 1316 if (ai == NULL) 1317 return NULL; 1318 1319 memcpy(ai, pai, sizeof(struct addrinfo)); 1320 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1321 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1322 ai->ai_addr->sa_len = afd->a_socklen; 1323 ai->ai_addrlen = afd->a_socklen; 1324 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1325 p = (char *)(void *)(ai->ai_addr); 1326 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1327 return ai; 1328 } 1329 1330 /* XXX need to malloc() the same way we do from other functions! */ 1331 static struct addrinfo * 1332 copy_ai(const struct addrinfo *pai) 1333 { 1334 struct addrinfo *ai; 1335 size_t l; 1336 1337 l = sizeof(*ai) + pai->ai_addrlen; 1338 if ((ai = (struct addrinfo *)malloc(l)) == NULL) 1339 return NULL; 1340 memset(ai, 0, l); 1341 memcpy(ai, pai, sizeof(*ai)); 1342 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1343 memcpy(ai->ai_addr, pai->ai_addr, pai->ai_addrlen); 1344 1345 if (pai->ai_canonname) { 1346 l = strlen(pai->ai_canonname) + 1; 1347 if ((ai->ai_canonname = malloc(l)) == NULL) { 1348 free(ai); 1349 return NULL; 1350 } 1351 strlcpy(ai->ai_canonname, pai->ai_canonname, l); 1352 } else { 1353 /* just to make sure */ 1354 ai->ai_canonname = NULL; 1355 } 1356 1357 ai->ai_next = NULL; 1358 1359 return ai; 1360 } 1361 1362 static int 1363 get_portmatch(const struct addrinfo *ai, const char *servname) 1364 { 1365 1366 /* get_port does not touch first argument when matchonly == 1. */ 1367 /* LINTED const cast */ 1368 return get_port((struct addrinfo *)ai, servname, 1); 1369 } 1370 1371 static int 1372 get_port(struct addrinfo *ai, const char *servname, int matchonly) 1373 { 1374 const char *proto; 1375 struct servent *sp; 1376 int port, error; 1377 int allownumeric; 1378 1379 if (servname == NULL) 1380 return 0; 1381 switch (ai->ai_family) { 1382 case AF_INET: 1383 #ifdef AF_INET6 1384 case AF_INET6: 1385 #endif 1386 break; 1387 default: 1388 return 0; 1389 } 1390 1391 switch (ai->ai_socktype) { 1392 case SOCK_RAW: 1393 return EAI_SERVICE; 1394 case SOCK_DGRAM: 1395 case SOCK_STREAM: 1396 case SOCK_SEQPACKET: 1397 allownumeric = 1; 1398 break; 1399 case ANY: 1400 switch (ai->ai_family) { 1401 case AF_INET: 1402 #ifdef AF_INET6 1403 case AF_INET6: 1404 #endif 1405 allownumeric = 1; 1406 break; 1407 default: 1408 allownumeric = 0; 1409 break; 1410 } 1411 break; 1412 default: 1413 return EAI_SOCKTYPE; 1414 } 1415 1416 error = str2number(servname, &port); 1417 if (error == 0) { 1418 if (!allownumeric) 1419 return EAI_SERVICE; 1420 if (port < 0 || port > 65535) 1421 return EAI_SERVICE; 1422 port = htons(port); 1423 } else { 1424 if (ai->ai_flags & AI_NUMERICSERV) 1425 return EAI_NONAME; 1426 1427 switch (ai->ai_protocol) { 1428 case IPPROTO_UDP: 1429 proto = "udp"; 1430 break; 1431 case IPPROTO_TCP: 1432 proto = "tcp"; 1433 break; 1434 case IPPROTO_SCTP: 1435 proto = "sctp"; 1436 break; 1437 case IPPROTO_UDPLITE: 1438 proto = "udplite"; 1439 break; 1440 default: 1441 proto = NULL; 1442 break; 1443 } 1444 1445 if ((sp = getservbyname(servname, proto)) == NULL) 1446 return EAI_SERVICE; 1447 port = sp->s_port; 1448 } 1449 1450 if (!matchonly) { 1451 switch (ai->ai_family) { 1452 case AF_INET: 1453 ((struct sockaddr_in *)(void *) 1454 ai->ai_addr)->sin_port = port; 1455 break; 1456 #ifdef INET6 1457 case AF_INET6: 1458 ((struct sockaddr_in6 *)(void *) 1459 ai->ai_addr)->sin6_port = port; 1460 break; 1461 #endif 1462 } 1463 } 1464 1465 return 0; 1466 } 1467 1468 static const struct afd * 1469 find_afd(int af) 1470 { 1471 const struct afd *afd; 1472 1473 if (af == PF_UNSPEC) 1474 return NULL; 1475 for (afd = afdl; afd->a_af; afd++) { 1476 if (afd->a_af == af) 1477 return afd; 1478 } 1479 return NULL; 1480 } 1481 1482 /* 1483 * RFC 3493: AI_ADDRCONFIG check. Determines which address families are 1484 * configured on the local system and correlates with pai->ai_family value. 1485 * If an address family is not configured on the system, it will not be 1486 * queried for. For this purpose, loopback addresses are not considered 1487 * configured addresses. 1488 * 1489 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1490 * _dns_getaddrinfo. 1491 */ 1492 static int 1493 addrconfig(struct addrinfo *pai) 1494 { 1495 struct ifaddrs *ifaddrs, *ifa; 1496 struct sockaddr_in *sin; 1497 #ifdef INET6 1498 struct sockaddr_in6 *sin6; 1499 #endif 1500 int seen_inet = 0, seen_inet6 = 0; 1501 1502 if (getifaddrs(&ifaddrs) != 0) 1503 return (0); 1504 1505 for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) { 1506 if (ifa->ifa_addr == NULL || (ifa->ifa_flags & IFF_UP) == 0) 1507 continue; 1508 switch (ifa->ifa_addr->sa_family) { 1509 case AF_INET: 1510 if (seen_inet) 1511 continue; 1512 sin = (struct sockaddr_in *)(ifa->ifa_addr); 1513 if (IN_LOOPBACK(htonl(sin->sin_addr.s_addr))) 1514 continue; 1515 seen_inet = 1; 1516 break; 1517 #ifdef INET6 1518 case AF_INET6: 1519 if (seen_inet6) 1520 continue; 1521 sin6 = (struct sockaddr_in6 *)(ifa->ifa_addr); 1522 if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr)) 1523 continue; 1524 if ((ifa->ifa_flags & IFT_LOOP) != 0 && 1525 IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) 1526 continue; 1527 if (is_ifdisabled(ifa->ifa_name)) 1528 continue; 1529 seen_inet6 = 1; 1530 break; 1531 #endif 1532 } 1533 } 1534 freeifaddrs(ifaddrs); 1535 1536 switch(pai->ai_family) { 1537 case AF_INET6: 1538 return (seen_inet6); 1539 case AF_INET: 1540 return (seen_inet); 1541 case AF_UNSPEC: 1542 if (seen_inet == seen_inet6) 1543 return (seen_inet); 1544 pai->ai_family = seen_inet ? AF_INET : AF_INET6; 1545 return (1); 1546 } 1547 return (1); 1548 } 1549 1550 #ifdef INET6 1551 static int 1552 is_ifdisabled(char *name) 1553 { 1554 struct in6_ndireq nd; 1555 int fd; 1556 1557 if ((fd = _socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, 0)) < 0) 1558 return (-1); 1559 memset(&nd, 0, sizeof(nd)); 1560 strlcpy(nd.ifname, name, sizeof(nd.ifname)); 1561 if (_ioctl(fd, SIOCGIFINFO_IN6, &nd) < 0) { 1562 _close(fd); 1563 return (-1); 1564 } 1565 _close(fd); 1566 return ((nd.ndi.flags & ND6_IFF_IFDISABLED) != 0); 1567 } 1568 1569 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1570 static int 1571 ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid) 1572 { 1573 u_long lscopeid; 1574 struct in6_addr *a6; 1575 char *ep; 1576 1577 a6 = &sin6->sin6_addr; 1578 1579 /* empty scopeid portion is invalid */ 1580 if (*scope == '\0') 1581 return -1; 1582 1583 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6) || 1584 IN6_IS_ADDR_MC_NODELOCAL(a6)) { 1585 /* 1586 * We currently assume a one-to-one mapping between links 1587 * and interfaces, so we simply use interface indices for 1588 * like-local scopes. 1589 */ 1590 *scopeid = if_nametoindex(scope); 1591 if (*scopeid == 0) 1592 goto trynumeric; 1593 return 0; 1594 } 1595 1596 /* still unclear about literal, allow numeric only - placeholder */ 1597 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1598 goto trynumeric; 1599 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1600 goto trynumeric; 1601 else 1602 goto trynumeric; /* global */ 1603 1604 /* try to convert to a numeric id as a last resort */ 1605 trynumeric: 1606 errno = 0; 1607 lscopeid = strtoul(scope, &ep, 10); 1608 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1609 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1610 return 0; 1611 else 1612 return -1; 1613 } 1614 #endif 1615 1616 1617 #ifdef NS_CACHING 1618 static int 1619 addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap, 1620 void *cache_mdata) 1621 { 1622 res_state statp; 1623 u_long res_options; 1624 1625 const int op_id = 0; /* identifies the getaddrinfo for the cache */ 1626 char *hostname; 1627 struct addrinfo *hints; 1628 1629 char *p; 1630 int ai_flags, ai_family, ai_socktype, ai_protocol; 1631 size_t desired_size, size; 1632 1633 statp = __res_state(); 1634 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES | 1635 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6); 1636 1637 hostname = va_arg(ap, char *); 1638 hints = va_arg(ap, struct addrinfo *); 1639 1640 desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4; 1641 if (hostname != NULL) { 1642 size = strlen(hostname); 1643 desired_size += size + 1; 1644 } else 1645 size = 0; 1646 1647 if (desired_size > *buffer_size) { 1648 *buffer_size = desired_size; 1649 return (NS_RETURN); 1650 } 1651 1652 if (hints == NULL) 1653 ai_flags = ai_family = ai_socktype = ai_protocol = 0; 1654 else { 1655 ai_flags = hints->ai_flags; 1656 ai_family = hints->ai_family; 1657 ai_socktype = hints->ai_socktype; 1658 ai_protocol = hints->ai_protocol; 1659 } 1660 1661 p = buffer; 1662 memcpy(p, &res_options, sizeof(res_options)); 1663 p += sizeof(res_options); 1664 1665 memcpy(p, &op_id, sizeof(int)); 1666 p += sizeof(int); 1667 1668 memcpy(p, &ai_flags, sizeof(int)); 1669 p += sizeof(int); 1670 1671 memcpy(p, &ai_family, sizeof(int)); 1672 p += sizeof(int); 1673 1674 memcpy(p, &ai_socktype, sizeof(int)); 1675 p += sizeof(int); 1676 1677 memcpy(p, &ai_protocol, sizeof(int)); 1678 p += sizeof(int); 1679 1680 if (hostname != NULL) 1681 memcpy(p, hostname, size); 1682 1683 *buffer_size = desired_size; 1684 return (NS_SUCCESS); 1685 } 1686 1687 static int 1688 addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval, 1689 va_list ap, void *cache_mdata) 1690 { 1691 struct addrinfo *ai, *cai; 1692 char *p; 1693 size_t desired_size, size, ai_size; 1694 1695 ai = *((struct addrinfo **)retval); 1696 1697 desired_size = sizeof(size_t); 1698 ai_size = 0; 1699 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1700 desired_size += sizeof(struct addrinfo) + cai->ai_addrlen; 1701 if (cai->ai_canonname != NULL) 1702 desired_size += sizeof(size_t) + 1703 strlen(cai->ai_canonname); 1704 ++ai_size; 1705 } 1706 1707 if (desired_size > *buffer_size) { 1708 /* this assignment is here for future use */ 1709 errno = ERANGE; 1710 *buffer_size = desired_size; 1711 return (NS_RETURN); 1712 } 1713 1714 memset(buffer, 0, desired_size); 1715 p = buffer; 1716 1717 memcpy(p, &ai_size, sizeof(size_t)); 1718 p += sizeof(size_t); 1719 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1720 memcpy(p, cai, sizeof(struct addrinfo)); 1721 p += sizeof(struct addrinfo); 1722 1723 memcpy(p, cai->ai_addr, cai->ai_addrlen); 1724 p += cai->ai_addrlen; 1725 1726 if (cai->ai_canonname != NULL) { 1727 size = strlen(cai->ai_canonname); 1728 memcpy(p, &size, sizeof(size_t)); 1729 p += sizeof(size_t); 1730 1731 memcpy(p, cai->ai_canonname, size); 1732 p += size; 1733 } 1734 } 1735 1736 return (NS_SUCCESS); 1737 } 1738 1739 static int 1740 addrinfo_unmarshal_func(char *buffer, size_t buffer_size, void *retval, 1741 va_list ap, void *cache_mdata) 1742 { 1743 struct addrinfo new_ai, *result, *sentinel, *lasts; 1744 1745 char *p; 1746 size_t ai_size, ai_i, size; 1747 1748 p = buffer; 1749 memcpy(&ai_size, p, sizeof(size_t)); 1750 p += sizeof(size_t); 1751 1752 result = NULL; 1753 lasts = NULL; 1754 for (ai_i = 0; ai_i < ai_size; ++ai_i) { 1755 memcpy(&new_ai, p, sizeof(struct addrinfo)); 1756 p += sizeof(struct addrinfo); 1757 size = new_ai.ai_addrlen + sizeof(struct addrinfo) + 1758 _ALIGNBYTES; 1759 1760 sentinel = (struct addrinfo *)malloc(size); 1761 memset(sentinel, 0, size); 1762 1763 memcpy(sentinel, &new_ai, sizeof(struct addrinfo)); 1764 sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel + 1765 sizeof(struct addrinfo)); 1766 1767 memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen); 1768 p += new_ai.ai_addrlen; 1769 1770 if (new_ai.ai_canonname != NULL) { 1771 memcpy(&size, p, sizeof(size_t)); 1772 p += sizeof(size_t); 1773 1774 sentinel->ai_canonname = (char *)malloc(size + 1); 1775 memset(sentinel->ai_canonname, 0, size + 1); 1776 1777 memcpy(sentinel->ai_canonname, p, size); 1778 p += size; 1779 } 1780 1781 if (result == NULL) { 1782 result = sentinel; 1783 lasts = sentinel; 1784 } else { 1785 lasts->ai_next = sentinel; 1786 lasts = sentinel; 1787 } 1788 } 1789 1790 *((struct addrinfo **)retval) = result; 1791 return (NS_SUCCESS); 1792 } 1793 #endif /* NS_CACHING */ 1794 1795 /* 1796 * FQDN hostname, DNS lookup 1797 */ 1798 static int 1799 explore_fqdn(const struct addrinfo *pai, const char *hostname, 1800 const char *servname, struct addrinfo **res) 1801 { 1802 struct addrinfo *result; 1803 struct addrinfo *cur; 1804 int error = 0; 1805 1806 #ifdef NS_CACHING 1807 static const nss_cache_info cache_info = 1808 NS_COMMON_CACHE_INFO_INITIALIZER( 1809 hosts, NULL, addrinfo_id_func, addrinfo_marshal_func, 1810 addrinfo_unmarshal_func); 1811 #endif 1812 static const ns_dtab dtab[] = { 1813 NS_FILES_CB(_files_getaddrinfo, NULL) 1814 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1815 NS_NIS_CB(_yp_getaddrinfo, NULL) 1816 #ifdef NS_CACHING 1817 NS_CACHE_CB(&cache_info) 1818 #endif 1819 { 0 } 1820 }; 1821 1822 result = NULL; 1823 1824 /* 1825 * if the servname does not match socktype/protocol, ignore it. 1826 */ 1827 if (get_portmatch(pai, servname) != 0) 1828 return 0; 1829 1830 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1831 default_dns_files, hostname, pai)) { 1832 case NS_TRYAGAIN: 1833 error = EAI_AGAIN; 1834 goto free; 1835 case NS_UNAVAIL: 1836 error = EAI_FAIL; 1837 goto free; 1838 case NS_NOTFOUND: 1839 error = EAI_NONAME; 1840 goto free; 1841 case NS_SUCCESS: 1842 error = 0; 1843 for (cur = result; cur; cur = cur->ai_next) { 1844 GET_PORT(cur, servname); 1845 /* canonname should be filled already */ 1846 } 1847 break; 1848 } 1849 1850 *res = result; 1851 1852 return 0; 1853 1854 free: 1855 if (result) 1856 freeaddrinfo(result); 1857 return error; 1858 } 1859 1860 #ifdef DEBUG 1861 static const char AskedForGot[] = 1862 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1863 #endif 1864 1865 static struct addrinfo * 1866 getanswer(const querybuf *answer, int anslen, const char *qname, int qtype, 1867 const struct addrinfo *pai, res_state res) 1868 { 1869 struct addrinfo sentinel, *cur; 1870 struct addrinfo ai; 1871 const struct afd *afd; 1872 char *canonname; 1873 const HEADER *hp; 1874 const u_char *cp; 1875 int n; 1876 const u_char *eom; 1877 char *bp, *ep; 1878 int type, class, ancount, qdcount; 1879 int haveanswer, had_error; 1880 char tbuf[MAXDNAME]; 1881 int (*name_ok)(const char *); 1882 char hostbuf[8*1024]; 1883 1884 memset(&sentinel, 0, sizeof(sentinel)); 1885 cur = &sentinel; 1886 1887 canonname = NULL; 1888 eom = answer->buf + anslen; 1889 switch (qtype) { 1890 case T_A: 1891 case T_AAAA: 1892 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1893 name_ok = res_hnok; 1894 break; 1895 default: 1896 return (NULL); /* XXX should be abort(); */ 1897 } 1898 /* 1899 * find first satisfactory answer 1900 */ 1901 hp = &answer->hdr; 1902 ancount = ntohs(hp->ancount); 1903 qdcount = ntohs(hp->qdcount); 1904 bp = hostbuf; 1905 ep = hostbuf + sizeof hostbuf; 1906 cp = answer->buf + HFIXEDSZ; 1907 if (qdcount != 1) { 1908 RES_SET_H_ERRNO(res, NO_RECOVERY); 1909 return (NULL); 1910 } 1911 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1912 if ((n < 0) || !(*name_ok)(bp)) { 1913 RES_SET_H_ERRNO(res, NO_RECOVERY); 1914 return (NULL); 1915 } 1916 cp += n + QFIXEDSZ; 1917 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1918 /* res_send() has already verified that the query name is the 1919 * same as the one we sent; this just gets the expanded name 1920 * (i.e., with the succeeding search-domain tacked on). 1921 */ 1922 n = strlen(bp) + 1; /* for the \0 */ 1923 if (n >= MAXHOSTNAMELEN) { 1924 RES_SET_H_ERRNO(res, NO_RECOVERY); 1925 return (NULL); 1926 } 1927 canonname = bp; 1928 bp += n; 1929 /* The qname can be abbreviated, but h_name is now absolute. */ 1930 qname = canonname; 1931 } 1932 haveanswer = 0; 1933 had_error = 0; 1934 while (ancount-- > 0 && cp < eom && !had_error) { 1935 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1936 if ((n < 0) || !(*name_ok)(bp)) { 1937 had_error++; 1938 continue; 1939 } 1940 cp += n; /* name */ 1941 type = _getshort(cp); 1942 cp += INT16SZ; /* type */ 1943 class = _getshort(cp); 1944 cp += INT16SZ + INT32SZ; /* class, TTL */ 1945 n = _getshort(cp); 1946 cp += INT16SZ; /* len */ 1947 if (class != C_IN) { 1948 /* XXX - debug? syslog? */ 1949 cp += n; 1950 continue; /* XXX - had_error++ ? */ 1951 } 1952 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1953 type == T_CNAME) { 1954 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1955 if ((n < 0) || !(*name_ok)(tbuf)) { 1956 had_error++; 1957 continue; 1958 } 1959 cp += n; 1960 /* Get canonical name. */ 1961 n = strlen(tbuf) + 1; /* for the \0 */ 1962 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1963 had_error++; 1964 continue; 1965 } 1966 strlcpy(bp, tbuf, ep - bp); 1967 canonname = bp; 1968 bp += n; 1969 continue; 1970 } 1971 if (qtype == T_ANY) { 1972 if (!(type == T_A || type == T_AAAA)) { 1973 cp += n; 1974 continue; 1975 } 1976 } else if (type != qtype) { 1977 #ifdef DEBUG 1978 if (type != T_KEY && type != T_SIG && 1979 type != ns_t_dname) 1980 syslog(LOG_NOTICE|LOG_AUTH, 1981 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1982 qname, p_class(C_IN), p_type(qtype), 1983 p_type(type)); 1984 #endif 1985 cp += n; 1986 continue; /* XXX - had_error++ ? */ 1987 } 1988 switch (type) { 1989 case T_A: 1990 case T_AAAA: 1991 if (strcasecmp(canonname, bp) != 0) { 1992 #ifdef DEBUG 1993 syslog(LOG_NOTICE|LOG_AUTH, 1994 AskedForGot, canonname, bp); 1995 #endif 1996 cp += n; 1997 continue; /* XXX - had_error++ ? */ 1998 } 1999 if (type == T_A && n != INADDRSZ) { 2000 cp += n; 2001 continue; 2002 } 2003 if (type == T_AAAA && n != IN6ADDRSZ) { 2004 cp += n; 2005 continue; 2006 } 2007 #ifdef FILTER_V4MAPPED 2008 if (type == T_AAAA) { 2009 struct in6_addr in6; 2010 memcpy(&in6, cp, sizeof(in6)); 2011 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 2012 cp += n; 2013 continue; 2014 } 2015 } 2016 #endif 2017 if (!haveanswer) { 2018 int nn; 2019 2020 canonname = bp; 2021 nn = strlen(bp) + 1; /* for the \0 */ 2022 bp += nn; 2023 } 2024 2025 /* don't overwrite pai */ 2026 ai = *pai; 2027 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 2028 afd = find_afd(ai.ai_family); 2029 if (afd == NULL) { 2030 cp += n; 2031 continue; 2032 } 2033 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 2034 if (cur->ai_next == NULL) 2035 had_error++; 2036 while (cur && cur->ai_next) 2037 cur = cur->ai_next; 2038 cp += n; 2039 break; 2040 default: 2041 abort(); 2042 } 2043 if (!had_error) 2044 haveanswer++; 2045 } 2046 if (haveanswer) { 2047 #if defined(RESOLVSORT) 2048 /* 2049 * We support only IPv4 address for backward 2050 * compatibility against gethostbyname(3). 2051 */ 2052 if (res->nsort && qtype == T_A) { 2053 if (addr4sort(&sentinel, res) < 0) { 2054 freeaddrinfo(sentinel.ai_next); 2055 RES_SET_H_ERRNO(res, NO_RECOVERY); 2056 return NULL; 2057 } 2058 } 2059 #endif /*RESOLVSORT*/ 2060 if (!canonname) 2061 (void)get_canonname(pai, sentinel.ai_next, qname); 2062 else 2063 (void)get_canonname(pai, sentinel.ai_next, canonname); 2064 RES_SET_H_ERRNO(res, NETDB_SUCCESS); 2065 return sentinel.ai_next; 2066 } 2067 2068 RES_SET_H_ERRNO(res, NO_RECOVERY); 2069 return NULL; 2070 } 2071 2072 #ifdef RESOLVSORT 2073 struct addr_ptr { 2074 struct addrinfo *ai; 2075 int aval; 2076 }; 2077 2078 static int 2079 addr4sort(struct addrinfo *sentinel, res_state res) 2080 { 2081 struct addrinfo *ai; 2082 struct addr_ptr *addrs, addr; 2083 struct sockaddr_in *sin; 2084 int naddrs, i, j; 2085 int needsort = 0; 2086 2087 if (!sentinel) 2088 return -1; 2089 naddrs = 0; 2090 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 2091 naddrs++; 2092 if (naddrs < 2) 2093 return 0; /* We don't need sorting. */ 2094 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 2095 return -1; 2096 i = 0; 2097 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 2098 sin = (struct sockaddr_in *)ai->ai_addr; 2099 for (j = 0; (unsigned)j < res->nsort; j++) { 2100 if (res->sort_list[j].addr.s_addr == 2101 (sin->sin_addr.s_addr & res->sort_list[j].mask)) 2102 break; 2103 } 2104 addrs[i].ai = ai; 2105 addrs[i].aval = j; 2106 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 2107 needsort = i; 2108 i++; 2109 } 2110 if (!needsort) { 2111 free(addrs); 2112 return 0; 2113 } 2114 2115 while (needsort < naddrs) { 2116 for (j = needsort - 1; j >= 0; j--) { 2117 if (addrs[j].aval > addrs[j+1].aval) { 2118 addr = addrs[j]; 2119 addrs[j] = addrs[j + 1]; 2120 addrs[j + 1] = addr; 2121 } else 2122 break; 2123 } 2124 needsort++; 2125 } 2126 2127 ai = sentinel; 2128 for (i = 0; i < naddrs; ++i) { 2129 ai->ai_next = addrs[i].ai; 2130 ai = ai->ai_next; 2131 } 2132 ai->ai_next = NULL; 2133 free(addrs); 2134 return 0; 2135 } 2136 #endif /*RESOLVSORT*/ 2137 2138 /*ARGSUSED*/ 2139 static int 2140 _dns_getaddrinfo(void *rv, void *cb_data, va_list ap) 2141 { 2142 struct addrinfo *ai; 2143 querybuf *buf, *buf2; 2144 const char *hostname; 2145 const struct addrinfo *pai; 2146 struct addrinfo sentinel, *cur; 2147 struct res_target q, q2; 2148 res_state res; 2149 2150 hostname = va_arg(ap, char *); 2151 pai = va_arg(ap, const struct addrinfo *); 2152 2153 memset(&q, 0, sizeof(q)); 2154 memset(&q2, 0, sizeof(q2)); 2155 memset(&sentinel, 0, sizeof(sentinel)); 2156 cur = &sentinel; 2157 2158 buf = malloc(sizeof(*buf)); 2159 if (!buf) { 2160 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2161 return NS_NOTFOUND; 2162 } 2163 buf2 = malloc(sizeof(*buf2)); 2164 if (!buf2) { 2165 free(buf); 2166 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2167 return NS_NOTFOUND; 2168 } 2169 2170 switch (pai->ai_family) { 2171 case AF_UNSPEC: 2172 q.name = hostname; 2173 q.qclass = C_IN; 2174 q.qtype = T_A; 2175 q.answer = buf->buf; 2176 q.anslen = sizeof(buf->buf); 2177 q.next = &q2; 2178 q2.name = hostname; 2179 q2.qclass = C_IN; 2180 q2.qtype = T_AAAA; 2181 q2.answer = buf2->buf; 2182 q2.anslen = sizeof(buf2->buf); 2183 break; 2184 case AF_INET: 2185 q.name = hostname; 2186 q.qclass = C_IN; 2187 q.qtype = T_A; 2188 q.answer = buf->buf; 2189 q.anslen = sizeof(buf->buf); 2190 break; 2191 case AF_INET6: 2192 q.name = hostname; 2193 q.qclass = C_IN; 2194 q.qtype = T_AAAA; 2195 q.answer = buf->buf; 2196 q.anslen = sizeof(buf->buf); 2197 break; 2198 default: 2199 free(buf); 2200 free(buf2); 2201 return NS_UNAVAIL; 2202 } 2203 2204 res = __res_state(); 2205 if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) { 2206 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2207 free(buf); 2208 free(buf2); 2209 return NS_NOTFOUND; 2210 } 2211 2212 if (res_searchN(hostname, &q, res) < 0) { 2213 free(buf); 2214 free(buf2); 2215 return NS_NOTFOUND; 2216 } 2217 /* prefer IPv6 */ 2218 if (q.next) { 2219 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res); 2220 if (ai) { 2221 cur->ai_next = ai; 2222 while (cur && cur->ai_next) 2223 cur = cur->ai_next; 2224 } 2225 } 2226 ai = getanswer(buf, q.n, q.name, q.qtype, pai, res); 2227 if (ai) 2228 cur->ai_next = ai; 2229 free(buf); 2230 free(buf2); 2231 if (sentinel.ai_next == NULL) 2232 switch (res->res_h_errno) { 2233 case HOST_NOT_FOUND: 2234 return NS_NOTFOUND; 2235 case TRY_AGAIN: 2236 return NS_TRYAGAIN; 2237 default: 2238 return NS_UNAVAIL; 2239 } 2240 *((struct addrinfo **)rv) = sentinel.ai_next; 2241 return NS_SUCCESS; 2242 } 2243 2244 static void 2245 _sethtent(FILE **hostf) 2246 { 2247 if (!*hostf) 2248 *hostf = fopen(_PATH_HOSTS, "re"); 2249 else 2250 rewind(*hostf); 2251 } 2252 2253 static void 2254 _endhtent(FILE **hostf) 2255 { 2256 if (*hostf) { 2257 (void) fclose(*hostf); 2258 *hostf = NULL; 2259 } 2260 } 2261 2262 static struct addrinfo * 2263 _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2264 { 2265 char *p; 2266 char *cp, *tname, *cname; 2267 struct addrinfo hints, *res0, *res; 2268 int error; 2269 const char *addr; 2270 char hostbuf[8*1024]; 2271 2272 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "re"))) 2273 return (NULL); 2274 again: 2275 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 2276 return (NULL); 2277 if (*p == '#') 2278 goto again; 2279 cp = strpbrk(p, "#\n"); 2280 if (cp != NULL) 2281 *cp = '\0'; 2282 if (!(cp = strpbrk(p, " \t"))) 2283 goto again; 2284 *cp++ = '\0'; 2285 addr = p; 2286 cname = NULL; 2287 /* if this is not something we're looking for, skip it. */ 2288 while (cp && *cp) { 2289 if (*cp == ' ' || *cp == '\t') { 2290 cp++; 2291 continue; 2292 } 2293 tname = cp; 2294 if (cname == NULL) 2295 cname = cp; 2296 if ((cp = strpbrk(cp, " \t")) != NULL) 2297 *cp++ = '\0'; 2298 if (strcasecmp(name, tname) == 0) 2299 goto found; 2300 } 2301 goto again; 2302 2303 found: 2304 /* we should not glob socktype/protocol here */ 2305 memset(&hints, 0, sizeof(hints)); 2306 hints.ai_family = pai->ai_family; 2307 hints.ai_socktype = SOCK_DGRAM; 2308 hints.ai_protocol = 0; 2309 hints.ai_flags = AI_NUMERICHOST; 2310 error = getaddrinfo(addr, "0", &hints, &res0); 2311 if (error) 2312 goto again; 2313 #ifdef FILTER_V4MAPPED 2314 /* XXX should check all items in the chain */ 2315 if (res0->ai_family == AF_INET6 && 2316 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2317 freeaddrinfo(res0); 2318 goto again; 2319 } 2320 #endif 2321 for (res = res0; res; res = res->ai_next) { 2322 /* cover it up */ 2323 res->ai_flags = pai->ai_flags; 2324 res->ai_socktype = pai->ai_socktype; 2325 res->ai_protocol = pai->ai_protocol; 2326 2327 if (pai->ai_flags & AI_CANONNAME) { 2328 if (get_canonname(pai, res, cname) != 0) { 2329 freeaddrinfo(res0); 2330 goto again; 2331 } 2332 } 2333 } 2334 return res0; 2335 } 2336 2337 /*ARGSUSED*/ 2338 static int 2339 _files_getaddrinfo(void *rv, void *cb_data, va_list ap) 2340 { 2341 const char *name; 2342 const struct addrinfo *pai; 2343 struct addrinfo sentinel, *cur; 2344 struct addrinfo *p; 2345 FILE *hostf = NULL; 2346 2347 name = va_arg(ap, char *); 2348 pai = va_arg(ap, struct addrinfo *); 2349 2350 memset(&sentinel, 0, sizeof(sentinel)); 2351 cur = &sentinel; 2352 2353 _sethtent(&hostf); 2354 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2355 cur->ai_next = p; 2356 while (cur && cur->ai_next) 2357 cur = cur->ai_next; 2358 } 2359 _endhtent(&hostf); 2360 2361 *((struct addrinfo **)rv) = sentinel.ai_next; 2362 if (sentinel.ai_next == NULL) 2363 return NS_NOTFOUND; 2364 return NS_SUCCESS; 2365 } 2366 2367 #ifdef YP 2368 /*ARGSUSED*/ 2369 static struct addrinfo * 2370 _yphostent(char *line, const struct addrinfo *pai) 2371 { 2372 struct addrinfo sentinel, *cur; 2373 struct addrinfo hints, *res, *res0; 2374 int error; 2375 char *p = line; 2376 const char *addr, *canonname; 2377 char *nextline; 2378 char *cp; 2379 2380 addr = canonname = NULL; 2381 2382 memset(&sentinel, 0, sizeof(sentinel)); 2383 cur = &sentinel; 2384 2385 nextline: 2386 /* terminate line */ 2387 cp = strchr(p, '\n'); 2388 if (cp) { 2389 *cp++ = '\0'; 2390 nextline = cp; 2391 } else 2392 nextline = NULL; 2393 2394 cp = strpbrk(p, " \t"); 2395 if (cp == NULL) { 2396 if (canonname == NULL) 2397 return (NULL); 2398 else 2399 goto done; 2400 } 2401 *cp++ = '\0'; 2402 2403 addr = p; 2404 2405 while (cp && *cp) { 2406 if (*cp == ' ' || *cp == '\t') { 2407 cp++; 2408 continue; 2409 } 2410 if (!canonname) 2411 canonname = cp; 2412 if ((cp = strpbrk(cp, " \t")) != NULL) 2413 *cp++ = '\0'; 2414 } 2415 2416 hints = *pai; 2417 hints.ai_flags = AI_NUMERICHOST; 2418 error = getaddrinfo(addr, NULL, &hints, &res0); 2419 if (error == 0) { 2420 for (res = res0; res; res = res->ai_next) { 2421 /* cover it up */ 2422 res->ai_flags = pai->ai_flags; 2423 2424 if (pai->ai_flags & AI_CANONNAME) 2425 (void)get_canonname(pai, res, canonname); 2426 } 2427 } else 2428 res0 = NULL; 2429 if (res0) { 2430 cur->ai_next = res0; 2431 while (cur && cur->ai_next) 2432 cur = cur->ai_next; 2433 } 2434 2435 if (nextline) { 2436 p = nextline; 2437 goto nextline; 2438 } 2439 2440 done: 2441 return sentinel.ai_next; 2442 } 2443 2444 /*ARGSUSED*/ 2445 static int 2446 _yp_getaddrinfo(void *rv, void *cb_data, va_list ap) 2447 { 2448 struct addrinfo sentinel, *cur; 2449 struct addrinfo *ai = NULL; 2450 char *ypbuf; 2451 int ypbuflen, r; 2452 const char *name; 2453 const struct addrinfo *pai; 2454 char *ypdomain; 2455 2456 if (_yp_check(&ypdomain) == 0) 2457 return NS_UNAVAIL; 2458 2459 name = va_arg(ap, char *); 2460 pai = va_arg(ap, const struct addrinfo *); 2461 2462 memset(&sentinel, 0, sizeof(sentinel)); 2463 cur = &sentinel; 2464 2465 /* hosts.byname is only for IPv4 (Solaris8) */ 2466 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2467 r = yp_match(ypdomain, "hosts.byname", name, 2468 (int)strlen(name), &ypbuf, &ypbuflen); 2469 if (r == 0) { 2470 struct addrinfo ai4; 2471 2472 ai4 = *pai; 2473 ai4.ai_family = AF_INET; 2474 ai = _yphostent(ypbuf, &ai4); 2475 if (ai) { 2476 cur->ai_next = ai; 2477 while (cur && cur->ai_next) 2478 cur = cur->ai_next; 2479 } 2480 free(ypbuf); 2481 } 2482 } 2483 2484 /* ipnodes.byname can hold both IPv4/v6 */ 2485 r = yp_match(ypdomain, "ipnodes.byname", name, 2486 (int)strlen(name), &ypbuf, &ypbuflen); 2487 if (r == 0) { 2488 ai = _yphostent(ypbuf, pai); 2489 if (ai) 2490 cur->ai_next = ai; 2491 free(ypbuf); 2492 } 2493 2494 if (sentinel.ai_next == NULL) { 2495 RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND); 2496 return NS_NOTFOUND; 2497 } 2498 *((struct addrinfo **)rv) = sentinel.ai_next; 2499 return NS_SUCCESS; 2500 } 2501 #endif 2502 2503 /* resolver logic */ 2504 2505 /* 2506 * Formulate a normal query, send, and await answer. 2507 * Returned answer is placed in supplied buffer "answer". 2508 * Perform preliminary check of answer, returning success only 2509 * if no error is indicated and the answer count is nonzero. 2510 * Return the size of the response on success, -1 on error. 2511 * Error number is left in h_errno. 2512 * 2513 * Caller must parse answer and determine whether it answers the question. 2514 */ 2515 static int 2516 res_queryN(const char *name, struct res_target *target, res_state res) 2517 { 2518 u_char *buf; 2519 HEADER *hp; 2520 int n; 2521 u_int oflags; 2522 struct res_target *t; 2523 int rcode; 2524 int ancount; 2525 2526 rcode = NOERROR; 2527 ancount = 0; 2528 2529 buf = malloc(MAXPACKET); 2530 if (!buf) { 2531 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2532 return -1; 2533 } 2534 2535 for (t = target; t; t = t->next) { 2536 int class, type; 2537 u_char *answer; 2538 int anslen; 2539 2540 hp = (HEADER *)(void *)t->answer; 2541 2542 /* make it easier... */ 2543 class = t->qclass; 2544 type = t->qtype; 2545 answer = t->answer; 2546 anslen = t->anslen; 2547 2548 oflags = res->_flags; 2549 2550 again: 2551 hp->rcode = NOERROR; /* default */ 2552 2553 #ifdef DEBUG 2554 if (res->options & RES_DEBUG) 2555 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2556 #endif 2557 2558 n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL, 2559 buf, MAXPACKET); 2560 if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 && 2561 (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U) 2562 n = res_nopt(res, n, buf, MAXPACKET, anslen); 2563 if (n <= 0) { 2564 #ifdef DEBUG 2565 if (res->options & RES_DEBUG) 2566 printf(";; res_query: mkquery failed\n"); 2567 #endif 2568 free(buf); 2569 RES_SET_H_ERRNO(res, NO_RECOVERY); 2570 return (n); 2571 } 2572 n = res_nsend(res, buf, n, answer, anslen); 2573 if (n < 0) { 2574 /* 2575 * if the query choked with EDNS0, retry 2576 * without EDNS0 2577 */ 2578 if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) 2579 != 0U && 2580 ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) { 2581 res->_flags |= RES_F_EDNS0ERR; 2582 if (res->options & RES_DEBUG) 2583 printf(";; res_nquery: retry without EDNS0\n"); 2584 goto again; 2585 } 2586 rcode = hp->rcode; /* record most recent error */ 2587 #ifdef DEBUG 2588 if (res->options & RES_DEBUG) 2589 printf(";; res_query: send error\n"); 2590 #endif 2591 continue; 2592 } 2593 2594 if (n > anslen) 2595 hp->rcode = FORMERR; /* XXX not very informative */ 2596 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2597 rcode = hp->rcode; /* record most recent error */ 2598 #ifdef DEBUG 2599 if (res->options & RES_DEBUG) 2600 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2601 ntohs(hp->ancount)); 2602 #endif 2603 continue; 2604 } 2605 2606 ancount += ntohs(hp->ancount); 2607 2608 t->n = n; 2609 } 2610 2611 free(buf); 2612 2613 if (ancount == 0) { 2614 switch (rcode) { 2615 case NXDOMAIN: 2616 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); 2617 break; 2618 case SERVFAIL: 2619 RES_SET_H_ERRNO(res, TRY_AGAIN); 2620 break; 2621 case NOERROR: 2622 RES_SET_H_ERRNO(res, NO_DATA); 2623 break; 2624 case FORMERR: 2625 case NOTIMP: 2626 case REFUSED: 2627 default: 2628 RES_SET_H_ERRNO(res, NO_RECOVERY); 2629 break; 2630 } 2631 return (-1); 2632 } 2633 return (ancount); 2634 } 2635 2636 /* 2637 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2638 * Return the size of the response on success, -1 on error. 2639 * If enabled, implement search rules until answer or unrecoverable failure 2640 * is detected. Error code, if any, is left in h_errno. 2641 */ 2642 static int 2643 res_searchN(const char *name, struct res_target *target, res_state res) 2644 { 2645 const char *cp, * const *domain; 2646 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2647 u_int dots; 2648 int trailing_dot, ret, saved_herrno; 2649 int got_nodata = 0, got_servfail = 0, root_on_list = 0; 2650 int tried_as_is = 0; 2651 int searched = 0; 2652 char abuf[MAXDNAME]; 2653 2654 errno = 0; 2655 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */ 2656 dots = 0; 2657 for (cp = name; *cp; cp++) 2658 dots += (*cp == '.'); 2659 trailing_dot = 0; 2660 if (cp > name && *--cp == '.') 2661 trailing_dot++; 2662 2663 /* 2664 * if there aren't any dots, it could be a user-level alias 2665 */ 2666 if (!dots && 2667 (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL) 2668 return (res_queryN(cp, target, res)); 2669 2670 /* 2671 * If there are enough dots in the name, let's just give it a 2672 * try 'as is'. The threshold can be set with the "ndots" option. 2673 * Also, query 'as is', if there is a trailing dot in the name. 2674 */ 2675 saved_herrno = -1; 2676 if (dots >= res->ndots || trailing_dot) { 2677 ret = res_querydomainN(name, NULL, target, res); 2678 if (ret > 0 || trailing_dot) 2679 return (ret); 2680 if (errno == ECONNREFUSED) { 2681 RES_SET_H_ERRNO(res, TRY_AGAIN); 2682 return (-1); 2683 } 2684 switch (res->res_h_errno) { 2685 case NO_DATA: 2686 case HOST_NOT_FOUND: 2687 break; 2688 case TRY_AGAIN: 2689 if (hp->rcode == SERVFAIL) 2690 break; 2691 /* FALLTHROUGH */ 2692 default: 2693 return (-1); 2694 } 2695 saved_herrno = res->res_h_errno; 2696 tried_as_is++; 2697 } 2698 2699 /* 2700 * We do at least one level of search if 2701 * - there is no dot and RES_DEFNAME is set, or 2702 * - there is at least one dot, there is no trailing dot, 2703 * and RES_DNSRCH is set. 2704 */ 2705 if ((!dots && (res->options & RES_DEFNAMES)) || 2706 (dots && !trailing_dot && (res->options & RES_DNSRCH))) { 2707 int done = 0; 2708 2709 for (domain = (const char * const *)res->dnsrch; 2710 *domain && !done; 2711 domain++) { 2712 searched = 1; 2713 2714 if (domain[0][0] == '\0' || 2715 (domain[0][0] == '.' && domain[0][1] == '\0')) 2716 root_on_list++; 2717 2718 if (root_on_list && tried_as_is) 2719 continue; 2720 2721 ret = res_querydomainN(name, *domain, target, res); 2722 if (ret > 0) 2723 return (ret); 2724 2725 /* 2726 * If no server present, give up. 2727 * If name isn't found in this domain, 2728 * keep trying higher domains in the search list 2729 * (if that's enabled). 2730 * On a NO_DATA error, keep trying, otherwise 2731 * a wildcard entry of another type could keep us 2732 * from finding this entry higher in the domain. 2733 * If we get some other error (negative answer or 2734 * server failure), then stop searching up, 2735 * but try the input name below in case it's 2736 * fully-qualified. 2737 */ 2738 if (errno == ECONNREFUSED) { 2739 RES_SET_H_ERRNO(res, TRY_AGAIN); 2740 return (-1); 2741 } 2742 2743 switch (res->res_h_errno) { 2744 case NO_DATA: 2745 got_nodata++; 2746 /* FALLTHROUGH */ 2747 case HOST_NOT_FOUND: 2748 /* keep trying */ 2749 break; 2750 case TRY_AGAIN: 2751 got_servfail++; 2752 if (hp->rcode == SERVFAIL) { 2753 /* try next search element, if any */ 2754 break; 2755 } 2756 /* FALLTHROUGH */ 2757 default: 2758 /* anything else implies that we're done */ 2759 done++; 2760 } 2761 /* 2762 * if we got here for some reason other than DNSRCH, 2763 * we only wanted one iteration of the loop, so stop. 2764 */ 2765 if (!(res->options & RES_DNSRCH)) 2766 done++; 2767 } 2768 } 2769 2770 switch (res->res_h_errno) { 2771 case NO_DATA: 2772 case HOST_NOT_FOUND: 2773 break; 2774 case TRY_AGAIN: 2775 if (hp->rcode == SERVFAIL) 2776 break; 2777 /* FALLTHROUGH */ 2778 default: 2779 goto giveup; 2780 } 2781 2782 /* 2783 * If the query has not already been tried as is then try it 2784 * unless RES_NOTLDQUERY is set and there were no dots. 2785 */ 2786 if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) && 2787 !(tried_as_is || root_on_list)) { 2788 ret = res_querydomainN(name, NULL, target, res); 2789 if (ret > 0) 2790 return (ret); 2791 } 2792 2793 /* 2794 * if we got here, we didn't satisfy the search. 2795 * if we did an initial full query, return that query's h_errno 2796 * (note that we wouldn't be here if that query had succeeded). 2797 * else if we ever got a nodata, send that back as the reason. 2798 * else send back meaningless h_errno, that being the one from 2799 * the last DNSRCH we did. 2800 */ 2801 giveup: 2802 if (saved_herrno != -1) 2803 RES_SET_H_ERRNO(res, saved_herrno); 2804 else if (got_nodata) 2805 RES_SET_H_ERRNO(res, NO_DATA); 2806 else if (got_servfail) 2807 RES_SET_H_ERRNO(res, TRY_AGAIN); 2808 return (-1); 2809 } 2810 2811 /* 2812 * Perform a call on res_query on the concatenation of name and domain, 2813 * removing a trailing dot from name if domain is NULL. 2814 */ 2815 static int 2816 res_querydomainN(const char *name, const char *domain, 2817 struct res_target *target, res_state res) 2818 { 2819 char nbuf[MAXDNAME]; 2820 const char *longname = nbuf; 2821 size_t n, d; 2822 2823 #ifdef DEBUG 2824 if (res->options & RES_DEBUG) 2825 printf(";; res_querydomain(%s, %s)\n", 2826 name, domain?domain:"<Nil>"); 2827 #endif 2828 if (domain == NULL) { 2829 /* 2830 * Check for trailing '.'; 2831 * copy without '.' if present. 2832 */ 2833 n = strlen(name); 2834 if (n >= MAXDNAME) { 2835 RES_SET_H_ERRNO(res, NO_RECOVERY); 2836 return (-1); 2837 } 2838 if (n > 0 && name[--n] == '.') { 2839 strncpy(nbuf, name, n); 2840 nbuf[n] = '\0'; 2841 } else 2842 longname = name; 2843 } else { 2844 n = strlen(name); 2845 d = strlen(domain); 2846 if (n + d + 1 >= MAXDNAME) { 2847 RES_SET_H_ERRNO(res, NO_RECOVERY); 2848 return (-1); 2849 } 2850 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2851 } 2852 return (res_queryN(longname, target, res)); 2853 } 2854