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 * - Return values. There are nonstandard return values defined and used 37 * in the source code. This is because RFC2553 is silent about which error 38 * code must be returned for which situation. 39 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 40 * invalid. current code - SEGV on freeaddrinfo(NULL) 41 * 42 * Note: 43 * - The code filters out AFs that are not supported by the kernel, 44 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 45 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 46 * in ai_flags? 47 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 48 * (1) what should we do against numeric hostname (2) what should we do 49 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 50 * non-loopback address configured? global address configured? 51 * 52 * OS specific notes for freebsd4: 53 * - FreeBSD supported $GAI. The code does not. 54 */ 55 56 #include <sys/cdefs.h> 57 __FBSDID("$FreeBSD$"); 58 59 #include "namespace.h" 60 #include <sys/types.h> 61 #include <sys/param.h> 62 #include <sys/socket.h> 63 #include <net/if.h> 64 #include <netinet/in.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> /* XXX */ 71 #endif 72 #include <arpa/inet.h> 73 #include <arpa/nameser.h> 74 #include <rpc/rpc.h> 75 #include <rpcsvc/yp_prot.h> 76 #include <rpcsvc/ypclnt.h> 77 #include <netdb.h> 78 #include <resolv.h> 79 #include <string.h> 80 #include <stdlib.h> 81 #include <stddef.h> 82 #include <ctype.h> 83 #include <unistd.h> 84 #include <stdio.h> 85 #include <errno.h> 86 87 #include "res_config.h" 88 89 #ifdef DEBUG 90 #include <syslog.h> 91 #endif 92 93 #include <stdarg.h> 94 #include <nsswitch.h> 95 #include "un-namespace.h" 96 #include "libc_private.h" 97 #ifdef NS_CACHING 98 #include "nscache.h" 99 #endif 100 101 #if defined(__KAME__) && defined(INET6) 102 # define FAITH 103 #endif 104 105 #define SUCCESS 0 106 #define ANY 0 107 #define YES 1 108 #define NO 0 109 110 static const char in_addrany[] = { 0, 0, 0, 0 }; 111 static const char in_loopback[] = { 127, 0, 0, 1 }; 112 #ifdef INET6 113 static const char in6_addrany[] = { 114 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 115 }; 116 static const char in6_loopback[] = { 117 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 118 }; 119 #endif 120 121 struct policyqueue { 122 TAILQ_ENTRY(policyqueue) pc_entry; 123 #ifdef INET6 124 struct in6_addrpolicy pc_policy; 125 #endif 126 }; 127 TAILQ_HEAD(policyhead, policyqueue); 128 129 static const struct afd { 130 int a_af; 131 int a_addrlen; 132 socklen_t a_socklen; 133 int a_off; 134 const char *a_addrany; 135 const char *a_loopback; 136 int a_scoped; 137 } afdl [] = { 138 #ifdef INET6 139 #define N_INET6 0 140 {PF_INET6, sizeof(struct in6_addr), 141 sizeof(struct sockaddr_in6), 142 offsetof(struct sockaddr_in6, sin6_addr), 143 in6_addrany, in6_loopback, 1}, 144 #define N_INET 1 145 #else 146 #define N_INET 0 147 #endif 148 {PF_INET, sizeof(struct in_addr), 149 sizeof(struct sockaddr_in), 150 offsetof(struct sockaddr_in, sin_addr), 151 in_addrany, in_loopback, 0}, 152 {0, 0, 0, 0, NULL, NULL, 0}, 153 }; 154 155 struct explore { 156 int e_af; 157 int e_socktype; 158 int e_protocol; 159 const char *e_protostr; 160 int e_wild; 161 #define WILD_AF(ex) ((ex)->e_wild & 0x01) 162 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 163 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 164 }; 165 166 static const struct explore explore[] = { 167 #if 0 168 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 169 #endif 170 #ifdef INET6 171 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 172 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 173 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 174 #endif 175 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 176 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 177 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 178 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 179 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 180 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, 181 { -1, 0, 0, NULL, 0 }, 182 }; 183 184 #ifdef INET6 185 #define PTON_MAX 16 186 #else 187 #define PTON_MAX 4 188 #endif 189 190 #define AIO_SRCFLAG_DEPRECATED 0x1 191 192 struct ai_order { 193 union { 194 struct sockaddr_storage aiou_ss; 195 struct sockaddr aiou_sa; 196 } aio_src_un; 197 #define aio_srcsa aio_src_un.aiou_sa 198 u_int32_t aio_srcflag; 199 int aio_srcscope; 200 int aio_dstscope; 201 struct policyqueue *aio_srcpolicy; 202 struct policyqueue *aio_dstpolicy; 203 struct addrinfo *aio_ai; 204 int aio_matchlen; 205 }; 206 207 static const ns_src default_dns_files[] = { 208 { NSSRC_FILES, NS_SUCCESS }, 209 { NSSRC_DNS, NS_SUCCESS }, 210 { 0 } 211 }; 212 213 struct res_target { 214 struct res_target *next; 215 const char *name; /* domain name */ 216 int qclass, qtype; /* class and type of query */ 217 u_char *answer; /* buffer to put answer */ 218 int anslen; /* size of answer buffer */ 219 int n; /* result length */ 220 }; 221 222 #define MAXPACKET (64*1024) 223 224 typedef union { 225 HEADER hdr; 226 u_char buf[MAXPACKET]; 227 } querybuf; 228 229 static int str2number(const char *, int *); 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 int get_portmatch(const struct addrinfo *, const char *); 241 static int get_port(struct addrinfo *, const char *, int); 242 static const struct afd *find_afd(int); 243 static int addrconfig(struct addrinfo *); 244 static void set_source(struct ai_order *, struct policyhead *); 245 static int comp_dst(const void *, const void *); 246 #ifdef INET6 247 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 248 #endif 249 static int gai_addr2scopetype(struct sockaddr *); 250 251 static int explore_fqdn(const struct addrinfo *, const char *, 252 const char *, struct addrinfo **); 253 254 static int reorder(struct addrinfo *); 255 static int get_addrselectpolicy(struct policyhead *); 256 static void free_addrselectpolicy(struct policyhead *); 257 static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 258 struct policyhead *); 259 static int matchlen(struct sockaddr *, struct sockaddr *); 260 261 static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 262 const struct addrinfo *, res_state); 263 #if defined(RESOLVSORT) 264 static int addr4sort(struct addrinfo *, res_state); 265 #endif 266 static int _dns_getaddrinfo(void *, void *, va_list); 267 static void _sethtent(FILE **); 268 static void _endhtent(FILE **); 269 static struct addrinfo *_gethtent(FILE **, const char *, 270 const struct addrinfo *); 271 static int _files_getaddrinfo(void *, void *, va_list); 272 #ifdef YP 273 static struct addrinfo *_yphostent(char *, const struct addrinfo *); 274 static int _yp_getaddrinfo(void *, void *, va_list); 275 #endif 276 #ifdef NS_CACHING 277 static int addrinfo_id_func(char *, size_t *, va_list, void *); 278 static int addrinfo_marshal_func(char *, size_t *, void *, va_list, void *); 279 static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, void *); 280 #endif 281 282 static int res_queryN(const char *, struct res_target *, res_state); 283 static int res_searchN(const char *, struct res_target *, res_state); 284 static int res_querydomainN(const char *, const char *, 285 struct res_target *, res_state); 286 287 /* XXX macros that make external reference is BAD. */ 288 289 #define GET_AI(ai, afd, addr) \ 290 do { \ 291 /* external reference: pai, error, and label free */ \ 292 (ai) = get_ai(pai, (afd), (addr)); \ 293 if ((ai) == NULL) { \ 294 error = EAI_MEMORY; \ 295 goto free; \ 296 } \ 297 } while (/*CONSTCOND*/0) 298 299 #define GET_PORT(ai, serv) \ 300 do { \ 301 /* external reference: error and label free */ \ 302 error = get_port((ai), (serv), 0); \ 303 if (error != 0) \ 304 goto free; \ 305 } while (/*CONSTCOND*/0) 306 307 #define GET_CANONNAME(ai, str) \ 308 do { \ 309 /* external reference: pai, error and label free */ \ 310 error = get_canonname(pai, (ai), (str)); \ 311 if (error != 0) \ 312 goto free; \ 313 } while (/*CONSTCOND*/0) 314 315 #define ERR(err) \ 316 do { \ 317 /* external reference: error, and label bad */ \ 318 error = (err); \ 319 goto bad; \ 320 /*NOTREACHED*/ \ 321 } while (/*CONSTCOND*/0) 322 323 #define MATCH_FAMILY(x, y, w) \ 324 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 325 #define MATCH(x, y, w) \ 326 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 327 328 void 329 freeaddrinfo(struct addrinfo *ai) 330 { 331 struct addrinfo *next; 332 333 do { 334 next = ai->ai_next; 335 if (ai->ai_canonname) 336 free(ai->ai_canonname); 337 /* no need to free(ai->ai_addr) */ 338 free(ai); 339 ai = next; 340 } while (ai); 341 } 342 343 static int 344 str2number(const char *p, int *portp) 345 { 346 char *ep; 347 unsigned long v; 348 349 if (*p == '\0') 350 return -1; 351 ep = NULL; 352 errno = 0; 353 v = strtoul(p, &ep, 10); 354 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) { 355 *portp = v; 356 return 0; 357 } else 358 return -1; 359 } 360 361 int 362 getaddrinfo(const char *hostname, const char *servname, 363 const struct addrinfo *hints, struct addrinfo **res) 364 { 365 struct addrinfo sentinel; 366 struct addrinfo *cur; 367 int error = 0; 368 struct addrinfo ai; 369 struct addrinfo ai0; 370 struct addrinfo *pai; 371 const struct explore *ex; 372 int numeric = 0; 373 374 memset(&sentinel, 0, sizeof(sentinel)); 375 cur = &sentinel; 376 pai = &ai; 377 pai->ai_flags = 0; 378 pai->ai_family = PF_UNSPEC; 379 pai->ai_socktype = ANY; 380 pai->ai_protocol = ANY; 381 pai->ai_addrlen = 0; 382 pai->ai_canonname = NULL; 383 pai->ai_addr = NULL; 384 pai->ai_next = NULL; 385 386 if (hostname == NULL && servname == NULL) 387 return EAI_NONAME; 388 if (hints) { 389 /* error check for hints */ 390 if (hints->ai_addrlen || hints->ai_canonname || 391 hints->ai_addr || hints->ai_next) 392 ERR(EAI_BADHINTS); /* xxx */ 393 if (hints->ai_flags & ~AI_MASK) 394 ERR(EAI_BADFLAGS); 395 switch (hints->ai_family) { 396 case PF_UNSPEC: 397 case PF_INET: 398 #ifdef INET6 399 case PF_INET6: 400 #endif 401 break; 402 default: 403 ERR(EAI_FAMILY); 404 } 405 memcpy(pai, hints, sizeof(*pai)); 406 407 /* 408 * if both socktype/protocol are specified, check if they 409 * are meaningful combination. 410 */ 411 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 412 for (ex = explore; ex->e_af >= 0; ex++) { 413 if (pai->ai_family != ex->e_af) 414 continue; 415 if (ex->e_socktype == ANY) 416 continue; 417 if (ex->e_protocol == ANY) 418 continue; 419 if (pai->ai_socktype == ex->e_socktype && 420 pai->ai_protocol != ex->e_protocol) { 421 ERR(EAI_BADHINTS); 422 } 423 } 424 } 425 } 426 427 /* 428 * check for special cases. (1) numeric servname is disallowed if 429 * socktype/protocol are left unspecified. (2) servname is disallowed 430 * for raw and other inet{,6} sockets. 431 */ 432 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 433 #ifdef PF_INET6 434 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 435 #endif 436 ) { 437 ai0 = *pai; /* backup *pai */ 438 439 if (pai->ai_family == PF_UNSPEC) { 440 #ifdef PF_INET6 441 pai->ai_family = PF_INET6; 442 #else 443 pai->ai_family = PF_INET; 444 #endif 445 } 446 error = get_portmatch(pai, servname); 447 if (error) 448 ERR(error); 449 450 *pai = ai0; 451 } 452 453 ai0 = *pai; 454 455 /* NULL hostname, or numeric hostname */ 456 for (ex = explore; ex->e_af >= 0; ex++) { 457 *pai = ai0; 458 459 /* PF_UNSPEC entries are prepared for DNS queries only */ 460 if (ex->e_af == PF_UNSPEC) 461 continue; 462 463 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 464 continue; 465 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 466 continue; 467 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 468 continue; 469 470 if (pai->ai_family == PF_UNSPEC) 471 pai->ai_family = ex->e_af; 472 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 473 pai->ai_socktype = ex->e_socktype; 474 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 475 pai->ai_protocol = ex->e_protocol; 476 477 if (hostname == NULL) 478 error = explore_null(pai, servname, &cur->ai_next); 479 else 480 error = explore_numeric_scope(pai, hostname, servname, 481 &cur->ai_next); 482 483 if (error) 484 goto free; 485 486 while (cur && cur->ai_next) 487 cur = cur->ai_next; 488 } 489 490 /* 491 * XXX 492 * If numreic representation of AF1 can be interpreted as FQDN 493 * representation of AF2, we need to think again about the code below. 494 */ 495 if (sentinel.ai_next) { 496 numeric = 1; 497 goto good; 498 } 499 500 if (hostname == NULL) 501 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 502 if (pai->ai_flags & AI_NUMERICHOST) 503 ERR(EAI_NONAME); 504 505 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 506 ERR(EAI_FAIL); 507 508 /* 509 * hostname as alphabetical name. 510 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 511 * outer loop by AFs. 512 */ 513 for (ex = explore; ex->e_af >= 0; ex++) { 514 *pai = ai0; 515 516 /* require exact match for family field */ 517 if (pai->ai_family != ex->e_af) 518 continue; 519 520 if (!MATCH(pai->ai_socktype, ex->e_socktype, 521 WILD_SOCKTYPE(ex))) { 522 continue; 523 } 524 if (!MATCH(pai->ai_protocol, ex->e_protocol, 525 WILD_PROTOCOL(ex))) { 526 continue; 527 } 528 529 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 530 pai->ai_socktype = ex->e_socktype; 531 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 532 pai->ai_protocol = ex->e_protocol; 533 534 error = explore_fqdn(pai, hostname, servname, 535 &cur->ai_next); 536 537 while (cur && cur->ai_next) 538 cur = cur->ai_next; 539 } 540 541 /* XXX inhibit errors if we have the result */ 542 if (sentinel.ai_next) 543 error = 0; 544 545 good: 546 /* 547 * ensure we return either: 548 * - error == 0, non-NULL *res 549 * - error != 0, NULL *res 550 */ 551 if (error == 0) { 552 if (sentinel.ai_next) { 553 /* 554 * If the returned entry is for an active connection, 555 * and the given name is not numeric, reorder the 556 * list, so that the application would try the list 557 * in the most efficient order. Since the head entry 558 * of the original list may contain ai_canonname and 559 * that entry may be moved elsewhere in the new list, 560 * we keep the pointer and will restore it in the new 561 * head entry. (Note that RFC3493 requires the head 562 * entry store it when requested by the caller). 563 */ 564 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 565 if (!numeric) { 566 char *canonname; 567 568 canonname = 569 sentinel.ai_next->ai_canonname; 570 sentinel.ai_next->ai_canonname = NULL; 571 (void)reorder(&sentinel); 572 if (sentinel.ai_next->ai_canonname == 573 NULL) { 574 sentinel.ai_next->ai_canonname 575 = canonname; 576 } else if (canonname != NULL) 577 free(canonname); 578 } 579 } 580 *res = sentinel.ai_next; 581 return SUCCESS; 582 } else 583 error = EAI_FAIL; 584 } 585 free: 586 bad: 587 if (sentinel.ai_next) 588 freeaddrinfo(sentinel.ai_next); 589 *res = NULL; 590 return error; 591 } 592 593 static int 594 reorder(struct addrinfo *sentinel) 595 { 596 struct addrinfo *ai, **aip; 597 struct ai_order *aio; 598 int i, n; 599 struct policyhead policyhead; 600 601 /* count the number of addrinfo elements for sorting. */ 602 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 603 ; 604 605 /* 606 * If the number is small enough, we can skip the reordering process. 607 */ 608 if (n <= 1) 609 return(n); 610 611 /* allocate a temporary array for sort and initialization of it. */ 612 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 613 return(n); /* give up reordering */ 614 memset(aio, 0, sizeof(*aio) * n); 615 616 /* retrieve address selection policy from the kernel */ 617 TAILQ_INIT(&policyhead); 618 if (!get_addrselectpolicy(&policyhead)) { 619 /* no policy is installed into kernel, we don't sort. */ 620 free(aio); 621 return (n); 622 } 623 624 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 625 aio[i].aio_ai = ai; 626 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 627 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 628 &policyhead); 629 set_source(&aio[i], &policyhead); 630 } 631 632 /* perform sorting. */ 633 qsort(aio, n, sizeof(*aio), comp_dst); 634 635 /* reorder the addrinfo chain. */ 636 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 637 *aip = aio[i].aio_ai; 638 aip = &aio[i].aio_ai->ai_next; 639 } 640 *aip = NULL; 641 642 /* cleanup and return */ 643 free(aio); 644 free_addrselectpolicy(&policyhead); 645 return(n); 646 } 647 648 static int 649 get_addrselectpolicy(struct policyhead *head) 650 { 651 #ifdef INET6 652 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 653 size_t l; 654 char *buf; 655 struct in6_addrpolicy *pol, *ep; 656 657 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 658 return (0); 659 if ((buf = malloc(l)) == NULL) 660 return (0); 661 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 662 free(buf); 663 return (0); 664 } 665 666 ep = (struct in6_addrpolicy *)(buf + l); 667 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 668 struct policyqueue *new; 669 670 if ((new = malloc(sizeof(*new))) == NULL) { 671 free_addrselectpolicy(head); /* make the list empty */ 672 break; 673 } 674 new->pc_policy = *pol; 675 TAILQ_INSERT_TAIL(head, new, pc_entry); 676 } 677 678 free(buf); 679 return (1); 680 #else 681 return (0); 682 #endif 683 } 684 685 static void 686 free_addrselectpolicy(struct policyhead *head) 687 { 688 struct policyqueue *ent, *nent; 689 690 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 691 nent = TAILQ_NEXT(ent, pc_entry); 692 TAILQ_REMOVE(head, ent, pc_entry); 693 free(ent); 694 } 695 } 696 697 static struct policyqueue * 698 match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 699 { 700 #ifdef INET6 701 struct policyqueue *ent, *bestent = NULL; 702 struct in6_addrpolicy *pol; 703 int matchlen, bestmatchlen = -1; 704 u_char *mp, *ep, *k, *p, m; 705 struct sockaddr_in6 key; 706 707 switch(addr->sa_family) { 708 case AF_INET6: 709 key = *(struct sockaddr_in6 *)addr; 710 break; 711 case AF_INET: 712 /* convert the address into IPv4-mapped IPv6 address. */ 713 memset(&key, 0, sizeof(key)); 714 key.sin6_family = AF_INET6; 715 key.sin6_len = sizeof(key); 716 key.sin6_addr.s6_addr[10] = 0xff; 717 key.sin6_addr.s6_addr[11] = 0xff; 718 memcpy(&key.sin6_addr.s6_addr[12], 719 &((struct sockaddr_in *)addr)->sin_addr, 4); 720 break; 721 default: 722 return(NULL); 723 } 724 725 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 726 pol = &ent->pc_policy; 727 matchlen = 0; 728 729 mp = (u_char *)&pol->addrmask.sin6_addr; 730 ep = mp + 16; /* XXX: scope field? */ 731 k = (u_char *)&key.sin6_addr; 732 p = (u_char *)&pol->addr.sin6_addr; 733 for (; mp < ep && *mp; mp++, k++, p++) { 734 m = *mp; 735 if ((*k & m) != *p) 736 goto next; /* not match */ 737 if (m == 0xff) /* short cut for a typical case */ 738 matchlen += 8; 739 else { 740 while (m >= 0x80) { 741 matchlen++; 742 m <<= 1; 743 } 744 } 745 } 746 747 /* matched. check if this is better than the current best. */ 748 if (matchlen > bestmatchlen) { 749 bestent = ent; 750 bestmatchlen = matchlen; 751 } 752 753 next: 754 continue; 755 } 756 757 return(bestent); 758 #else 759 return(NULL); 760 #endif 761 762 } 763 764 static void 765 set_source(struct ai_order *aio, struct policyhead *ph) 766 { 767 struct addrinfo ai = *aio->aio_ai; 768 struct sockaddr_storage ss; 769 socklen_t srclen; 770 int s; 771 772 /* set unspec ("no source is available"), just in case */ 773 aio->aio_srcsa.sa_family = AF_UNSPEC; 774 aio->aio_srcscope = -1; 775 776 switch(ai.ai_family) { 777 case AF_INET: 778 #ifdef INET6 779 case AF_INET6: 780 #endif 781 break; 782 default: /* ignore unsupported AFs explicitly */ 783 return; 784 } 785 786 /* XXX: make a dummy addrinfo to call connect() */ 787 ai.ai_socktype = SOCK_DGRAM; 788 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 789 ai.ai_next = NULL; 790 memset(&ss, 0, sizeof(ss)); 791 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 792 ai.ai_addr = (struct sockaddr *)&ss; 793 get_port(&ai, "1", 0); 794 795 /* open a socket to get the source address for the given dst */ 796 if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0) 797 return; /* give up */ 798 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 799 goto cleanup; 800 srclen = ai.ai_addrlen; 801 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 802 aio->aio_srcsa.sa_family = AF_UNSPEC; 803 goto cleanup; 804 } 805 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 806 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 807 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 808 #ifdef INET6 809 if (ai.ai_family == AF_INET6) { 810 struct in6_ifreq ifr6; 811 u_int32_t flags6; 812 813 /* XXX: interface name should not be hardcoded */ 814 strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name)); 815 memset(&ifr6, 0, sizeof(ifr6)); 816 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 817 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 818 flags6 = ifr6.ifr_ifru.ifru_flags6; 819 if ((flags6 & IN6_IFF_DEPRECATED)) 820 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 821 } 822 } 823 #endif 824 825 cleanup: 826 _close(s); 827 return; 828 } 829 830 static int 831 matchlen(struct sockaddr *src, struct sockaddr *dst) 832 { 833 int match = 0; 834 u_char *s, *d; 835 u_char *lim, r; 836 int addrlen; 837 838 switch (src->sa_family) { 839 #ifdef INET6 840 case AF_INET6: 841 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 842 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 843 addrlen = sizeof(struct in6_addr); 844 lim = s + addrlen; 845 break; 846 #endif 847 case AF_INET: 848 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; 849 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; 850 addrlen = sizeof(struct in_addr); 851 lim = s + addrlen; 852 break; 853 default: 854 return(0); 855 } 856 857 while (s < lim) 858 if ((r = (*d++ ^ *s++)) != 0) { 859 while (r < addrlen * 8) { 860 match++; 861 r <<= 1; 862 } 863 break; 864 } else 865 match += 8; 866 return(match); 867 } 868 869 static int 870 comp_dst(const void *arg1, const void *arg2) 871 { 872 const struct ai_order *dst1 = arg1, *dst2 = arg2; 873 874 /* 875 * Rule 1: Avoid unusable destinations. 876 * XXX: we currently do not consider if an appropriate route exists. 877 */ 878 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 879 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 880 return(-1); 881 } 882 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 883 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 884 return(1); 885 } 886 887 /* Rule 2: Prefer matching scope. */ 888 if (dst1->aio_dstscope == dst1->aio_srcscope && 889 dst2->aio_dstscope != dst2->aio_srcscope) { 890 return(-1); 891 } 892 if (dst1->aio_dstscope != dst1->aio_srcscope && 893 dst2->aio_dstscope == dst2->aio_srcscope) { 894 return(1); 895 } 896 897 /* Rule 3: Avoid deprecated addresses. */ 898 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 899 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 900 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 901 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 902 return(-1); 903 } 904 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 905 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 906 return(1); 907 } 908 } 909 910 /* Rule 4: Prefer home addresses. */ 911 /* XXX: not implemented yet */ 912 913 /* Rule 5: Prefer matching label. */ 914 #ifdef INET6 915 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 916 dst1->aio_srcpolicy->pc_policy.label == 917 dst1->aio_dstpolicy->pc_policy.label && 918 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 919 dst2->aio_srcpolicy->pc_policy.label != 920 dst2->aio_dstpolicy->pc_policy.label)) { 921 return(-1); 922 } 923 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 924 dst2->aio_srcpolicy->pc_policy.label == 925 dst2->aio_dstpolicy->pc_policy.label && 926 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 927 dst1->aio_srcpolicy->pc_policy.label != 928 dst1->aio_dstpolicy->pc_policy.label)) { 929 return(1); 930 } 931 #endif 932 933 /* Rule 6: Prefer higher precedence. */ 934 #ifdef INET6 935 if (dst1->aio_dstpolicy && 936 (dst2->aio_dstpolicy == NULL || 937 dst1->aio_dstpolicy->pc_policy.preced > 938 dst2->aio_dstpolicy->pc_policy.preced)) { 939 return(-1); 940 } 941 if (dst2->aio_dstpolicy && 942 (dst1->aio_dstpolicy == NULL || 943 dst2->aio_dstpolicy->pc_policy.preced > 944 dst1->aio_dstpolicy->pc_policy.preced)) { 945 return(1); 946 } 947 #endif 948 949 /* Rule 7: Prefer native transport. */ 950 /* XXX: not implemented yet */ 951 952 /* Rule 8: Prefer smaller scope. */ 953 if (dst1->aio_dstscope >= 0 && 954 dst1->aio_dstscope < dst2->aio_dstscope) { 955 return(-1); 956 } 957 if (dst2->aio_dstscope >= 0 && 958 dst2->aio_dstscope < dst1->aio_dstscope) { 959 return(1); 960 } 961 962 /* 963 * Rule 9: Use longest matching prefix. 964 * We compare the match length in a same AF only. 965 */ 966 if (dst1->aio_ai->ai_addr->sa_family == 967 dst2->aio_ai->ai_addr->sa_family) { 968 if (dst1->aio_matchlen > dst2->aio_matchlen) { 969 return(-1); 970 } 971 if (dst1->aio_matchlen < dst2->aio_matchlen) { 972 return(1); 973 } 974 } 975 976 /* Rule 10: Otherwise, leave the order unchanged. */ 977 return(-1); 978 } 979 980 /* 981 * Copy from scope.c. 982 * XXX: we should standardize the functions and link them as standard 983 * library. 984 */ 985 static int 986 gai_addr2scopetype(struct sockaddr *sa) 987 { 988 #ifdef INET6 989 struct sockaddr_in6 *sa6; 990 #endif 991 struct sockaddr_in *sa4; 992 993 switch(sa->sa_family) { 994 #ifdef INET6 995 case AF_INET6: 996 sa6 = (struct sockaddr_in6 *)sa; 997 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 998 /* just use the scope field of the multicast address */ 999 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1000 } 1001 /* 1002 * Unicast addresses: map scope type to corresponding scope 1003 * value defined for multcast addresses. 1004 * XXX: hardcoded scope type values are bad... 1005 */ 1006 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1007 return(1); /* node local scope */ 1008 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1009 return(2); /* link-local scope */ 1010 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1011 return(5); /* site-local scope */ 1012 return(14); /* global scope */ 1013 break; 1014 #endif 1015 case AF_INET: 1016 /* 1017 * IPv4 pseudo scoping according to RFC 3484. 1018 */ 1019 sa4 = (struct sockaddr_in *)sa; 1020 /* IPv4 autoconfiguration addresses have link-local scope. */ 1021 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1022 ((u_char *)&sa4->sin_addr)[1] == 254) 1023 return(2); 1024 /* Private addresses have site-local scope. */ 1025 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1026 (((u_char *)&sa4->sin_addr)[0] == 172 && 1027 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1028 (((u_char *)&sa4->sin_addr)[0] == 192 && 1029 ((u_char *)&sa4->sin_addr)[1] == 168)) 1030 return(14); /* XXX: It should be 5 unless NAT */ 1031 /* Loopback addresses have link-local scope. */ 1032 if (((u_char *)&sa4->sin_addr)[0] == 127) 1033 return(2); 1034 return(14); 1035 break; 1036 default: 1037 errno = EAFNOSUPPORT; /* is this a good error? */ 1038 return(-1); 1039 } 1040 } 1041 1042 /* 1043 * hostname == NULL. 1044 * passive socket -> anyaddr (0.0.0.0 or ::) 1045 * non-passive socket -> localhost (127.0.0.1 or ::1) 1046 */ 1047 static int 1048 explore_null(const struct addrinfo *pai, const char *servname, 1049 struct addrinfo **res) 1050 { 1051 int s; 1052 const struct afd *afd; 1053 struct addrinfo *ai; 1054 int error; 1055 1056 *res = NULL; 1057 ai = NULL; 1058 1059 /* 1060 * filter out AFs that are not supported by the kernel 1061 * XXX errno? 1062 */ 1063 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1064 if (s < 0) { 1065 if (errno != EMFILE) 1066 return 0; 1067 } else 1068 _close(s); 1069 1070 /* 1071 * if the servname does not match socktype/protocol, ignore it. 1072 */ 1073 if (get_portmatch(pai, servname) != 0) 1074 return 0; 1075 1076 afd = find_afd(pai->ai_family); 1077 if (afd == NULL) 1078 return 0; 1079 1080 if (pai->ai_flags & AI_PASSIVE) { 1081 GET_AI(ai, afd, afd->a_addrany); 1082 GET_PORT(ai, servname); 1083 } else { 1084 GET_AI(ai, afd, afd->a_loopback); 1085 GET_PORT(ai, servname); 1086 } 1087 1088 *res = ai; 1089 return 0; 1090 1091 free: 1092 if (ai != NULL) 1093 freeaddrinfo(ai); 1094 return error; 1095 } 1096 1097 /* 1098 * numeric hostname 1099 */ 1100 static int 1101 explore_numeric(const struct addrinfo *pai, const char *hostname, 1102 const char *servname, struct addrinfo **res, const char *canonname) 1103 { 1104 const struct afd *afd; 1105 struct addrinfo *ai; 1106 int error; 1107 char pton[PTON_MAX]; 1108 1109 *res = NULL; 1110 ai = NULL; 1111 1112 /* 1113 * if the servname does not match socktype/protocol, ignore it. 1114 */ 1115 if (get_portmatch(pai, servname) != 0) 1116 return 0; 1117 1118 afd = find_afd(pai->ai_family); 1119 if (afd == NULL) 1120 return 0; 1121 1122 switch (afd->a_af) { 1123 case AF_INET: 1124 /* 1125 * RFC3493 requires getaddrinfo() to accept AF_INET formats 1126 * that are accepted by inet_addr() and its family. The 1127 * accepted forms includes the "classful" one, which inet_pton 1128 * does not accept. So we need to separate the case for 1129 * AF_INET. 1130 */ 1131 if (inet_aton(hostname, (struct in_addr *)pton) != 1) 1132 return 0; 1133 break; 1134 default: 1135 if (inet_pton(afd->a_af, hostname, pton) != 1) 1136 return 0; 1137 break; 1138 } 1139 1140 if (pai->ai_family == afd->a_af) { 1141 GET_AI(ai, afd, pton); 1142 GET_PORT(ai, servname); 1143 if ((pai->ai_flags & AI_CANONNAME)) { 1144 /* 1145 * Set the numeric address itself as the canonical 1146 * name, based on a clarification in RFC3493. 1147 */ 1148 GET_CANONNAME(ai, canonname); 1149 } 1150 } else { 1151 /* 1152 * XXX: This should not happen since we already matched the AF 1153 * by find_afd. 1154 */ 1155 ERR(EAI_FAMILY); 1156 } 1157 1158 *res = ai; 1159 return 0; 1160 1161 free: 1162 bad: 1163 if (ai != NULL) 1164 freeaddrinfo(ai); 1165 return error; 1166 } 1167 1168 /* 1169 * numeric hostname with scope 1170 */ 1171 static int 1172 explore_numeric_scope(const struct addrinfo *pai, const char *hostname, 1173 const char *servname, struct addrinfo **res) 1174 { 1175 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 1176 return explore_numeric(pai, hostname, servname, res, hostname); 1177 #else 1178 const struct afd *afd; 1179 struct addrinfo *cur; 1180 int error; 1181 char *cp, *hostname2 = NULL, *scope, *addr; 1182 struct sockaddr_in6 *sin6; 1183 1184 /* 1185 * if the servname does not match socktype/protocol, ignore it. 1186 */ 1187 if (get_portmatch(pai, servname) != 0) 1188 return 0; 1189 1190 afd = find_afd(pai->ai_family); 1191 if (afd == NULL) 1192 return 0; 1193 1194 if (!afd->a_scoped) 1195 return explore_numeric(pai, hostname, servname, res, hostname); 1196 1197 cp = strchr(hostname, SCOPE_DELIMITER); 1198 if (cp == NULL) 1199 return explore_numeric(pai, hostname, servname, res, hostname); 1200 1201 /* 1202 * Handle special case of <scoped_address><delimiter><scope id> 1203 */ 1204 hostname2 = strdup(hostname); 1205 if (hostname2 == NULL) 1206 return EAI_MEMORY; 1207 /* terminate at the delimiter */ 1208 hostname2[cp - hostname] = '\0'; 1209 addr = hostname2; 1210 scope = cp + 1; 1211 1212 error = explore_numeric(pai, addr, servname, res, hostname); 1213 if (error == 0) { 1214 u_int32_t scopeid; 1215 1216 for (cur = *res; cur; cur = cur->ai_next) { 1217 if (cur->ai_family != AF_INET6) 1218 continue; 1219 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1220 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1221 free(hostname2); 1222 return(EAI_NONAME); /* XXX: is return OK? */ 1223 } 1224 sin6->sin6_scope_id = scopeid; 1225 } 1226 } 1227 1228 free(hostname2); 1229 1230 return error; 1231 #endif 1232 } 1233 1234 static int 1235 get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) 1236 { 1237 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1238 ai->ai_canonname = strdup(str); 1239 if (ai->ai_canonname == NULL) 1240 return EAI_MEMORY; 1241 } 1242 return 0; 1243 } 1244 1245 static struct addrinfo * 1246 get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) 1247 { 1248 char *p; 1249 struct addrinfo *ai; 1250 #ifdef FAITH 1251 struct in6_addr faith_prefix; 1252 char *fp_str; 1253 int translate = 0; 1254 #endif 1255 1256 #ifdef FAITH 1257 /* 1258 * Transfrom an IPv4 addr into a special IPv6 addr format for 1259 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1260 * 1261 * +-----------------------------------+------------+ 1262 * | faith prefix part (12 bytes) | embedded | 1263 * | | IPv4 addr part (4 bytes) 1264 * +-----------------------------------+------------+ 1265 * 1266 * faith prefix part is specified as ascii IPv6 addr format 1267 * in environmental variable GAI. 1268 * For FAITH to work correctly, routing to faith prefix must be 1269 * setup toward a machine where a FAITH daemon operates. 1270 * Also, the machine must enable some mechanizm 1271 * (e.g. faith interface hack) to divert those packet with 1272 * faith prefixed destination addr to user-land FAITH daemon. 1273 */ 1274 fp_str = getenv("GAI"); 1275 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1276 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1277 u_int32_t v4a; 1278 u_int8_t v4a_top; 1279 1280 memcpy(&v4a, addr, sizeof v4a); 1281 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1282 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1283 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1284 afd = &afdl[N_INET6]; 1285 memcpy(&faith_prefix.s6_addr[12], addr, 1286 sizeof(struct in_addr)); 1287 translate = 1; 1288 } 1289 } 1290 #endif 1291 1292 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1293 + (afd->a_socklen)); 1294 if (ai == NULL) 1295 return NULL; 1296 1297 memcpy(ai, pai, sizeof(struct addrinfo)); 1298 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1299 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1300 ai->ai_addr->sa_len = afd->a_socklen; 1301 ai->ai_addrlen = afd->a_socklen; 1302 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1303 p = (char *)(void *)(ai->ai_addr); 1304 #ifdef FAITH 1305 if (translate == 1) 1306 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1307 else 1308 #endif 1309 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1310 return ai; 1311 } 1312 1313 static int 1314 get_portmatch(const struct addrinfo *ai, const char *servname) 1315 { 1316 1317 /* get_port does not touch first argument when matchonly == 1. */ 1318 /* LINTED const cast */ 1319 return get_port((struct addrinfo *)ai, servname, 1); 1320 } 1321 1322 static int 1323 get_port(struct addrinfo *ai, const char *servname, int matchonly) 1324 { 1325 const char *proto; 1326 struct servent *sp; 1327 int port, error; 1328 int allownumeric; 1329 1330 if (servname == NULL) 1331 return 0; 1332 switch (ai->ai_family) { 1333 case AF_INET: 1334 #ifdef AF_INET6 1335 case AF_INET6: 1336 #endif 1337 break; 1338 default: 1339 return 0; 1340 } 1341 1342 switch (ai->ai_socktype) { 1343 case SOCK_RAW: 1344 return EAI_SERVICE; 1345 case SOCK_DGRAM: 1346 case SOCK_STREAM: 1347 allownumeric = 1; 1348 break; 1349 case ANY: 1350 allownumeric = 0; 1351 break; 1352 default: 1353 return EAI_SOCKTYPE; 1354 } 1355 1356 error = str2number(servname, &port); 1357 if (error == 0) { 1358 if (!allownumeric) 1359 return EAI_SERVICE; 1360 if (port < 0 || port > 65535) 1361 return EAI_SERVICE; 1362 port = htons(port); 1363 } else { 1364 if (ai->ai_flags & AI_NUMERICSERV) 1365 return EAI_NONAME; 1366 switch (ai->ai_socktype) { 1367 case SOCK_DGRAM: 1368 proto = "udp"; 1369 break; 1370 case SOCK_STREAM: 1371 proto = "tcp"; 1372 break; 1373 default: 1374 proto = NULL; 1375 break; 1376 } 1377 1378 if ((sp = getservbyname(servname, proto)) == NULL) 1379 return EAI_SERVICE; 1380 port = sp->s_port; 1381 } 1382 1383 if (!matchonly) { 1384 switch (ai->ai_family) { 1385 case AF_INET: 1386 ((struct sockaddr_in *)(void *) 1387 ai->ai_addr)->sin_port = port; 1388 break; 1389 #ifdef INET6 1390 case AF_INET6: 1391 ((struct sockaddr_in6 *)(void *) 1392 ai->ai_addr)->sin6_port = port; 1393 break; 1394 #endif 1395 } 1396 } 1397 1398 return 0; 1399 } 1400 1401 static const struct afd * 1402 find_afd(int af) 1403 { 1404 const struct afd *afd; 1405 1406 if (af == PF_UNSPEC) 1407 return NULL; 1408 for (afd = afdl; afd->a_af; afd++) { 1409 if (afd->a_af == af) 1410 return afd; 1411 } 1412 return NULL; 1413 } 1414 1415 /* 1416 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1417 * will take care of it. 1418 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1419 * if the code is right or not. 1420 * 1421 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1422 * _dns_getaddrinfo. 1423 */ 1424 static int 1425 addrconfig(struct addrinfo *pai) 1426 { 1427 int s, af; 1428 1429 /* 1430 * TODO: 1431 * Note that implementation dependent test for address 1432 * configuration should be done everytime called 1433 * (or apropriate interval), 1434 * because addresses will be dynamically assigned or deleted. 1435 */ 1436 af = pai->ai_family; 1437 if (af == AF_UNSPEC) { 1438 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1439 af = AF_INET; 1440 else { 1441 _close(s); 1442 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1443 af = AF_INET6; 1444 else 1445 _close(s); 1446 } 1447 } 1448 if (af != AF_UNSPEC) { 1449 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1450 return 0; 1451 _close(s); 1452 } 1453 pai->ai_family = af; 1454 return 1; 1455 } 1456 1457 #ifdef INET6 1458 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1459 static int 1460 ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid) 1461 { 1462 u_long lscopeid; 1463 struct in6_addr *a6; 1464 char *ep; 1465 1466 a6 = &sin6->sin6_addr; 1467 1468 /* empty scopeid portion is invalid */ 1469 if (*scope == '\0') 1470 return -1; 1471 1472 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1473 /* 1474 * We currently assume a one-to-one mapping between links 1475 * and interfaces, so we simply use interface indices for 1476 * like-local scopes. 1477 */ 1478 *scopeid = if_nametoindex(scope); 1479 if (*scopeid == 0) 1480 goto trynumeric; 1481 return 0; 1482 } 1483 1484 /* still unclear about literal, allow numeric only - placeholder */ 1485 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1486 goto trynumeric; 1487 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1488 goto trynumeric; 1489 else 1490 goto trynumeric; /* global */ 1491 1492 /* try to convert to a numeric id as a last resort */ 1493 trynumeric: 1494 errno = 0; 1495 lscopeid = strtoul(scope, &ep, 10); 1496 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1497 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1498 return 0; 1499 else 1500 return -1; 1501 } 1502 #endif 1503 1504 1505 #ifdef NS_CACHING 1506 static int 1507 addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap, 1508 void *cache_mdata) 1509 { 1510 res_state statp; 1511 u_long res_options; 1512 1513 const int op_id = 0; /* identifies the getaddrinfo for the cache */ 1514 char *hostname; 1515 struct addrinfo *hints; 1516 1517 char *p; 1518 int ai_flags, ai_family, ai_socktype, ai_protocol; 1519 size_t desired_size, size; 1520 1521 statp = __res_state(); 1522 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES | 1523 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6); 1524 1525 hostname = va_arg(ap, char *); 1526 hints = va_arg(ap, struct addrinfo *); 1527 1528 desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4; 1529 if (hostname != NULL) { 1530 size = strlen(hostname); 1531 desired_size += size + 1; 1532 } else 1533 size = 0; 1534 1535 if (desired_size > *buffer_size) { 1536 *buffer_size = desired_size; 1537 return (NS_RETURN); 1538 } 1539 1540 if (hints == NULL) 1541 ai_flags = ai_family = ai_socktype = ai_protocol = 0; 1542 else { 1543 ai_flags = hints->ai_flags; 1544 ai_family = hints->ai_family; 1545 ai_socktype = hints->ai_socktype; 1546 ai_protocol = hints->ai_protocol; 1547 } 1548 1549 p = buffer; 1550 memcpy(p, &res_options, sizeof(res_options)); 1551 p += sizeof(res_options); 1552 1553 memcpy(p, &op_id, sizeof(int)); 1554 p += sizeof(int); 1555 1556 memcpy(p, &ai_flags, sizeof(int)); 1557 p += sizeof(int); 1558 1559 memcpy(p, &ai_family, sizeof(int)); 1560 p += sizeof(int); 1561 1562 memcpy(p, &ai_socktype, sizeof(int)); 1563 p += sizeof(int); 1564 1565 memcpy(p, &ai_protocol, sizeof(int)); 1566 p += sizeof(int); 1567 1568 if (hostname != NULL) 1569 memcpy(p, hostname, size); 1570 1571 *buffer_size = desired_size; 1572 return (NS_SUCCESS); 1573 } 1574 1575 static int 1576 addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval, 1577 va_list ap, void *cache_mdata) 1578 { 1579 struct addrinfo *ai, *cai; 1580 char *p; 1581 size_t desired_size, size, ai_size; 1582 1583 ai = *((struct addrinfo **)retval); 1584 1585 desired_size = sizeof(size_t); 1586 ai_size = 0; 1587 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1588 desired_size += sizeof(struct addrinfo) + cai->ai_addrlen; 1589 if (cai->ai_canonname != NULL) 1590 desired_size += sizeof(size_t) + 1591 strlen(cai->ai_canonname); 1592 ++ai_size; 1593 } 1594 1595 if (desired_size > *buffer_size) { 1596 /* this assignment is here for future use */ 1597 errno = ERANGE; 1598 *buffer_size = desired_size; 1599 return (NS_RETURN); 1600 } 1601 1602 memset(buffer, 0, desired_size); 1603 p = buffer; 1604 1605 memcpy(p, &ai_size, sizeof(size_t)); 1606 p += sizeof(size_t); 1607 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1608 memcpy(p, cai, sizeof(struct addrinfo)); 1609 p += sizeof(struct addrinfo); 1610 1611 memcpy(p, cai->ai_addr, cai->ai_addrlen); 1612 p += cai->ai_addrlen; 1613 1614 if (cai->ai_canonname != NULL) { 1615 size = strlen(cai->ai_canonname); 1616 memcpy(p, &size, sizeof(size_t)); 1617 p += sizeof(size_t); 1618 1619 memcpy(p, cai->ai_canonname, size); 1620 p += size; 1621 } 1622 } 1623 1624 return (NS_SUCCESS); 1625 } 1626 1627 static int 1628 addrinfo_unmarshal_func(char *buffer, size_t buffer_size, void *retval, 1629 va_list ap, void *cache_mdata) 1630 { 1631 struct addrinfo new_ai, *result, *sentinel, *lasts; 1632 1633 char *p; 1634 size_t ai_size, ai_i, size; 1635 1636 p = buffer; 1637 memcpy(&ai_size, p, sizeof(size_t)); 1638 p += sizeof(size_t); 1639 1640 result = NULL; 1641 lasts = NULL; 1642 for (ai_i = 0; ai_i < ai_size; ++ai_i) { 1643 memcpy(&new_ai, p, sizeof(struct addrinfo)); 1644 p += sizeof(struct addrinfo); 1645 size = new_ai.ai_addrlen + sizeof(struct addrinfo) + 1646 _ALIGNBYTES; 1647 1648 sentinel = (struct addrinfo *)malloc(size); 1649 memset(sentinel, 0, size); 1650 1651 memcpy(sentinel, &new_ai, sizeof(struct addrinfo)); 1652 sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel + 1653 sizeof(struct addrinfo)); 1654 1655 memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen); 1656 p += new_ai.ai_addrlen; 1657 1658 if (new_ai.ai_canonname != NULL) { 1659 memcpy(&size, p, sizeof(size_t)); 1660 p += sizeof(size_t); 1661 1662 sentinel->ai_canonname = (char *)malloc(size + 1); 1663 memset(sentinel->ai_canonname, 0, size + 1); 1664 1665 memcpy(sentinel->ai_canonname, p, size); 1666 p += size; 1667 } 1668 1669 if (result == NULL) { 1670 result = sentinel; 1671 lasts = sentinel; 1672 } else { 1673 lasts->ai_next = sentinel; 1674 lasts = sentinel; 1675 } 1676 } 1677 1678 *((struct addrinfo **)retval) = result; 1679 return (NS_SUCCESS); 1680 } 1681 #endif /* NS_CACHING */ 1682 1683 /* 1684 * FQDN hostname, DNS lookup 1685 */ 1686 static int 1687 explore_fqdn(const struct addrinfo *pai, const char *hostname, 1688 const char *servname, struct addrinfo **res) 1689 { 1690 struct addrinfo *result; 1691 struct addrinfo *cur; 1692 int error = 0; 1693 1694 #ifdef NS_CACHING 1695 static const nss_cache_info cache_info = 1696 NS_COMMON_CACHE_INFO_INITIALIZER( 1697 hosts, NULL, addrinfo_id_func, addrinfo_marshal_func, 1698 addrinfo_unmarshal_func); 1699 #endif 1700 static const ns_dtab dtab[] = { 1701 NS_FILES_CB(_files_getaddrinfo, NULL) 1702 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1703 NS_NIS_CB(_yp_getaddrinfo, NULL) 1704 #ifdef NS_CACHING 1705 NS_CACHE_CB(&cache_info) 1706 #endif 1707 { 0 } 1708 }; 1709 1710 result = NULL; 1711 1712 /* 1713 * if the servname does not match socktype/protocol, ignore it. 1714 */ 1715 if (get_portmatch(pai, servname) != 0) 1716 return 0; 1717 1718 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1719 default_dns_files, hostname, pai)) { 1720 case NS_TRYAGAIN: 1721 error = EAI_AGAIN; 1722 goto free; 1723 case NS_UNAVAIL: 1724 error = EAI_FAIL; 1725 goto free; 1726 case NS_NOTFOUND: 1727 error = EAI_NONAME; 1728 goto free; 1729 case NS_SUCCESS: 1730 error = 0; 1731 for (cur = result; cur; cur = cur->ai_next) { 1732 GET_PORT(cur, servname); 1733 /* canonname should be filled already */ 1734 } 1735 break; 1736 } 1737 1738 *res = result; 1739 1740 return 0; 1741 1742 free: 1743 if (result) 1744 freeaddrinfo(result); 1745 return error; 1746 } 1747 1748 #ifdef DEBUG 1749 static const char AskedForGot[] = 1750 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1751 #endif 1752 1753 static struct addrinfo * 1754 getanswer(const querybuf *answer, int anslen, const char *qname, int qtype, 1755 const struct addrinfo *pai, res_state res) 1756 { 1757 struct addrinfo sentinel, *cur; 1758 struct addrinfo ai; 1759 const struct afd *afd; 1760 char *canonname; 1761 const HEADER *hp; 1762 const u_char *cp; 1763 int n; 1764 const u_char *eom; 1765 char *bp, *ep; 1766 int type, class, ancount, qdcount; 1767 int haveanswer, had_error; 1768 char tbuf[MAXDNAME]; 1769 int (*name_ok)(const char *); 1770 char hostbuf[8*1024]; 1771 1772 memset(&sentinel, 0, sizeof(sentinel)); 1773 cur = &sentinel; 1774 1775 canonname = NULL; 1776 eom = answer->buf + anslen; 1777 switch (qtype) { 1778 case T_A: 1779 case T_AAAA: 1780 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1781 name_ok = res_hnok; 1782 break; 1783 default: 1784 return (NULL); /* XXX should be abort(); */ 1785 } 1786 /* 1787 * find first satisfactory answer 1788 */ 1789 hp = &answer->hdr; 1790 ancount = ntohs(hp->ancount); 1791 qdcount = ntohs(hp->qdcount); 1792 bp = hostbuf; 1793 ep = hostbuf + sizeof hostbuf; 1794 cp = answer->buf + HFIXEDSZ; 1795 if (qdcount != 1) { 1796 RES_SET_H_ERRNO(res, NO_RECOVERY); 1797 return (NULL); 1798 } 1799 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1800 if ((n < 0) || !(*name_ok)(bp)) { 1801 RES_SET_H_ERRNO(res, NO_RECOVERY); 1802 return (NULL); 1803 } 1804 cp += n + QFIXEDSZ; 1805 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1806 /* res_send() has already verified that the query name is the 1807 * same as the one we sent; this just gets the expanded name 1808 * (i.e., with the succeeding search-domain tacked on). 1809 */ 1810 n = strlen(bp) + 1; /* for the \0 */ 1811 if (n >= MAXHOSTNAMELEN) { 1812 RES_SET_H_ERRNO(res, NO_RECOVERY); 1813 return (NULL); 1814 } 1815 canonname = bp; 1816 bp += n; 1817 /* The qname can be abbreviated, but h_name is now absolute. */ 1818 qname = canonname; 1819 } 1820 haveanswer = 0; 1821 had_error = 0; 1822 while (ancount-- > 0 && cp < eom && !had_error) { 1823 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1824 if ((n < 0) || !(*name_ok)(bp)) { 1825 had_error++; 1826 continue; 1827 } 1828 cp += n; /* name */ 1829 type = _getshort(cp); 1830 cp += INT16SZ; /* type */ 1831 class = _getshort(cp); 1832 cp += INT16SZ + INT32SZ; /* class, TTL */ 1833 n = _getshort(cp); 1834 cp += INT16SZ; /* len */ 1835 if (class != C_IN) { 1836 /* XXX - debug? syslog? */ 1837 cp += n; 1838 continue; /* XXX - had_error++ ? */ 1839 } 1840 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1841 type == T_CNAME) { 1842 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1843 if ((n < 0) || !(*name_ok)(tbuf)) { 1844 had_error++; 1845 continue; 1846 } 1847 cp += n; 1848 /* Get canonical name. */ 1849 n = strlen(tbuf) + 1; /* for the \0 */ 1850 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1851 had_error++; 1852 continue; 1853 } 1854 strlcpy(bp, tbuf, ep - bp); 1855 canonname = bp; 1856 bp += n; 1857 continue; 1858 } 1859 if (qtype == T_ANY) { 1860 if (!(type == T_A || type == T_AAAA)) { 1861 cp += n; 1862 continue; 1863 } 1864 } else if (type != qtype) { 1865 #ifdef DEBUG 1866 if (type != T_KEY && type != T_SIG && 1867 type != ns_t_dname) 1868 syslog(LOG_NOTICE|LOG_AUTH, 1869 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1870 qname, p_class(C_IN), p_type(qtype), 1871 p_type(type)); 1872 #endif 1873 cp += n; 1874 continue; /* XXX - had_error++ ? */ 1875 } 1876 switch (type) { 1877 case T_A: 1878 case T_AAAA: 1879 if (strcasecmp(canonname, bp) != 0) { 1880 #ifdef DEBUG 1881 syslog(LOG_NOTICE|LOG_AUTH, 1882 AskedForGot, canonname, bp); 1883 #endif 1884 cp += n; 1885 continue; /* XXX - had_error++ ? */ 1886 } 1887 if (type == T_A && n != INADDRSZ) { 1888 cp += n; 1889 continue; 1890 } 1891 if (type == T_AAAA && n != IN6ADDRSZ) { 1892 cp += n; 1893 continue; 1894 } 1895 #ifdef FILTER_V4MAPPED 1896 if (type == T_AAAA) { 1897 struct in6_addr in6; 1898 memcpy(&in6, cp, sizeof(in6)); 1899 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1900 cp += n; 1901 continue; 1902 } 1903 } 1904 #endif 1905 if (!haveanswer) { 1906 int nn; 1907 1908 canonname = bp; 1909 nn = strlen(bp) + 1; /* for the \0 */ 1910 bp += nn; 1911 } 1912 1913 /* don't overwrite pai */ 1914 ai = *pai; 1915 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1916 afd = find_afd(ai.ai_family); 1917 if (afd == NULL) { 1918 cp += n; 1919 continue; 1920 } 1921 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1922 if (cur->ai_next == NULL) 1923 had_error++; 1924 while (cur && cur->ai_next) 1925 cur = cur->ai_next; 1926 cp += n; 1927 break; 1928 default: 1929 abort(); 1930 } 1931 if (!had_error) 1932 haveanswer++; 1933 } 1934 if (haveanswer) { 1935 #if defined(RESOLVSORT) 1936 /* 1937 * We support only IPv4 address for backward 1938 * compatibility against gethostbyname(3). 1939 */ 1940 if (res->nsort && qtype == T_A) { 1941 if (addr4sort(&sentinel, res) < 0) { 1942 freeaddrinfo(sentinel.ai_next); 1943 RES_SET_H_ERRNO(res, NO_RECOVERY); 1944 return NULL; 1945 } 1946 } 1947 #endif /*RESOLVSORT*/ 1948 if (!canonname) 1949 (void)get_canonname(pai, sentinel.ai_next, qname); 1950 else 1951 (void)get_canonname(pai, sentinel.ai_next, canonname); 1952 RES_SET_H_ERRNO(res, NETDB_SUCCESS); 1953 return sentinel.ai_next; 1954 } 1955 1956 RES_SET_H_ERRNO(res, NO_RECOVERY); 1957 return NULL; 1958 } 1959 1960 #ifdef RESOLVSORT 1961 struct addr_ptr { 1962 struct addrinfo *ai; 1963 int aval; 1964 }; 1965 1966 static int 1967 addr4sort(struct addrinfo *sentinel, res_state res) 1968 { 1969 struct addrinfo *ai; 1970 struct addr_ptr *addrs, addr; 1971 struct sockaddr_in *sin; 1972 int naddrs, i, j; 1973 int needsort = 0; 1974 1975 if (!sentinel) 1976 return -1; 1977 naddrs = 0; 1978 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1979 naddrs++; 1980 if (naddrs < 2) 1981 return 0; /* We don't need sorting. */ 1982 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1983 return -1; 1984 i = 0; 1985 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1986 sin = (struct sockaddr_in *)ai->ai_addr; 1987 for (j = 0; (unsigned)j < res->nsort; j++) { 1988 if (res->sort_list[j].addr.s_addr == 1989 (sin->sin_addr.s_addr & res->sort_list[j].mask)) 1990 break; 1991 } 1992 addrs[i].ai = ai; 1993 addrs[i].aval = j; 1994 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1995 needsort = i; 1996 i++; 1997 } 1998 if (!needsort) { 1999 free(addrs); 2000 return 0; 2001 } 2002 2003 while (needsort < naddrs) { 2004 for (j = needsort - 1; j >= 0; j--) { 2005 if (addrs[j].aval > addrs[j+1].aval) { 2006 addr = addrs[j]; 2007 addrs[j] = addrs[j + 1]; 2008 addrs[j + 1] = addr; 2009 } else 2010 break; 2011 } 2012 needsort++; 2013 } 2014 2015 ai = sentinel; 2016 for (i = 0; i < naddrs; ++i) { 2017 ai->ai_next = addrs[i].ai; 2018 ai = ai->ai_next; 2019 } 2020 ai->ai_next = NULL; 2021 free(addrs); 2022 return 0; 2023 } 2024 #endif /*RESOLVSORT*/ 2025 2026 /*ARGSUSED*/ 2027 static int 2028 _dns_getaddrinfo(void *rv, void *cb_data, va_list ap) 2029 { 2030 struct addrinfo *ai; 2031 querybuf *buf, *buf2; 2032 const char *hostname; 2033 const struct addrinfo *pai; 2034 struct addrinfo sentinel, *cur; 2035 struct res_target q, q2; 2036 res_state res; 2037 2038 hostname = va_arg(ap, char *); 2039 pai = va_arg(ap, const struct addrinfo *); 2040 2041 memset(&q, 0, sizeof(q)); 2042 memset(&q2, 0, sizeof(q2)); 2043 memset(&sentinel, 0, sizeof(sentinel)); 2044 cur = &sentinel; 2045 2046 buf = malloc(sizeof(*buf)); 2047 if (!buf) { 2048 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2049 return NS_NOTFOUND; 2050 } 2051 buf2 = malloc(sizeof(*buf2)); 2052 if (!buf2) { 2053 free(buf); 2054 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2055 return NS_NOTFOUND; 2056 } 2057 2058 switch (pai->ai_family) { 2059 case AF_UNSPEC: 2060 q.name = hostname; 2061 q.qclass = C_IN; 2062 q.qtype = T_A; 2063 q.answer = buf->buf; 2064 q.anslen = sizeof(buf->buf); 2065 q.next = &q2; 2066 q2.name = hostname; 2067 q2.qclass = C_IN; 2068 q2.qtype = T_AAAA; 2069 q2.answer = buf2->buf; 2070 q2.anslen = sizeof(buf2->buf); 2071 break; 2072 case AF_INET: 2073 q.name = hostname; 2074 q.qclass = C_IN; 2075 q.qtype = T_A; 2076 q.answer = buf->buf; 2077 q.anslen = sizeof(buf->buf); 2078 break; 2079 case AF_INET6: 2080 q.name = hostname; 2081 q.qclass = C_IN; 2082 q.qtype = T_AAAA; 2083 q.answer = buf->buf; 2084 q.anslen = sizeof(buf->buf); 2085 break; 2086 default: 2087 free(buf); 2088 free(buf2); 2089 return NS_UNAVAIL; 2090 } 2091 2092 res = __res_state(); 2093 if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) { 2094 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2095 free(buf); 2096 free(buf2); 2097 return NS_NOTFOUND; 2098 } 2099 2100 if (res_searchN(hostname, &q, res) < 0) { 2101 free(buf); 2102 free(buf2); 2103 return NS_NOTFOUND; 2104 } 2105 /* prefer IPv6 */ 2106 if (q.next) { 2107 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res); 2108 if (ai) { 2109 cur->ai_next = ai; 2110 while (cur && cur->ai_next) 2111 cur = cur->ai_next; 2112 } 2113 } 2114 ai = getanswer(buf, q.n, q.name, q.qtype, pai, res); 2115 if (ai) 2116 cur->ai_next = ai; 2117 free(buf); 2118 free(buf2); 2119 if (sentinel.ai_next == NULL) 2120 switch (res->res_h_errno) { 2121 case HOST_NOT_FOUND: 2122 return NS_NOTFOUND; 2123 case TRY_AGAIN: 2124 return NS_TRYAGAIN; 2125 default: 2126 return NS_UNAVAIL; 2127 } 2128 *((struct addrinfo **)rv) = sentinel.ai_next; 2129 return NS_SUCCESS; 2130 } 2131 2132 static void 2133 _sethtent(FILE **hostf) 2134 { 2135 if (!*hostf) 2136 *hostf = fopen(_PATH_HOSTS, "r"); 2137 else 2138 rewind(*hostf); 2139 } 2140 2141 static void 2142 _endhtent(FILE **hostf) 2143 { 2144 if (*hostf) { 2145 (void) fclose(*hostf); 2146 *hostf = NULL; 2147 } 2148 } 2149 2150 static struct addrinfo * 2151 _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2152 { 2153 char *p; 2154 char *cp, *tname, *cname; 2155 struct addrinfo hints, *res0, *res; 2156 int error; 2157 const char *addr; 2158 char hostbuf[8*1024]; 2159 2160 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "r"))) 2161 return (NULL); 2162 again: 2163 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 2164 return (NULL); 2165 if (*p == '#') 2166 goto again; 2167 cp = strpbrk(p, "#\n"); 2168 if (cp != NULL) 2169 *cp = '\0'; 2170 if (!(cp = strpbrk(p, " \t"))) 2171 goto again; 2172 *cp++ = '\0'; 2173 addr = p; 2174 cname = NULL; 2175 /* if this is not something we're looking for, skip it. */ 2176 while (cp && *cp) { 2177 if (*cp == ' ' || *cp == '\t') { 2178 cp++; 2179 continue; 2180 } 2181 tname = cp; 2182 if (cname == NULL) 2183 cname = cp; 2184 if ((cp = strpbrk(cp, " \t")) != NULL) 2185 *cp++ = '\0'; 2186 if (strcasecmp(name, tname) == 0) 2187 goto found; 2188 } 2189 goto again; 2190 2191 found: 2192 /* we should not glob socktype/protocol here */ 2193 memset(&hints, 0, sizeof(hints)); 2194 hints.ai_family = pai->ai_family; 2195 hints.ai_socktype = SOCK_DGRAM; 2196 hints.ai_protocol = 0; 2197 hints.ai_flags = AI_NUMERICHOST; 2198 error = getaddrinfo(addr, "0", &hints, &res0); 2199 if (error) 2200 goto again; 2201 #ifdef FILTER_V4MAPPED 2202 /* XXX should check all items in the chain */ 2203 if (res0->ai_family == AF_INET6 && 2204 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2205 freeaddrinfo(res0); 2206 goto again; 2207 } 2208 #endif 2209 for (res = res0; res; res = res->ai_next) { 2210 /* cover it up */ 2211 res->ai_flags = pai->ai_flags; 2212 res->ai_socktype = pai->ai_socktype; 2213 res->ai_protocol = pai->ai_protocol; 2214 2215 if (pai->ai_flags & AI_CANONNAME) { 2216 if (get_canonname(pai, res, cname) != 0) { 2217 freeaddrinfo(res0); 2218 goto again; 2219 } 2220 } 2221 } 2222 return res0; 2223 } 2224 2225 /*ARGSUSED*/ 2226 static int 2227 _files_getaddrinfo(void *rv, void *cb_data, va_list ap) 2228 { 2229 const char *name; 2230 const struct addrinfo *pai; 2231 struct addrinfo sentinel, *cur; 2232 struct addrinfo *p; 2233 FILE *hostf = NULL; 2234 2235 name = va_arg(ap, char *); 2236 pai = va_arg(ap, struct addrinfo *); 2237 2238 memset(&sentinel, 0, sizeof(sentinel)); 2239 cur = &sentinel; 2240 2241 _sethtent(&hostf); 2242 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2243 cur->ai_next = p; 2244 while (cur && cur->ai_next) 2245 cur = cur->ai_next; 2246 } 2247 _endhtent(&hostf); 2248 2249 *((struct addrinfo **)rv) = sentinel.ai_next; 2250 if (sentinel.ai_next == NULL) 2251 return NS_NOTFOUND; 2252 return NS_SUCCESS; 2253 } 2254 2255 #ifdef YP 2256 /*ARGSUSED*/ 2257 static struct addrinfo * 2258 _yphostent(char *line, const struct addrinfo *pai) 2259 { 2260 struct addrinfo sentinel, *cur; 2261 struct addrinfo hints, *res, *res0; 2262 int error; 2263 char *p = line; 2264 const char *addr, *canonname; 2265 char *nextline; 2266 char *cp; 2267 2268 addr = canonname = NULL; 2269 2270 memset(&sentinel, 0, sizeof(sentinel)); 2271 cur = &sentinel; 2272 2273 nextline: 2274 /* terminate line */ 2275 cp = strchr(p, '\n'); 2276 if (cp) { 2277 *cp++ = '\0'; 2278 nextline = cp; 2279 } else 2280 nextline = NULL; 2281 2282 cp = strpbrk(p, " \t"); 2283 if (cp == NULL) { 2284 if (canonname == NULL) 2285 return (NULL); 2286 else 2287 goto done; 2288 } 2289 *cp++ = '\0'; 2290 2291 addr = p; 2292 2293 while (cp && *cp) { 2294 if (*cp == ' ' || *cp == '\t') { 2295 cp++; 2296 continue; 2297 } 2298 if (!canonname) 2299 canonname = cp; 2300 if ((cp = strpbrk(cp, " \t")) != NULL) 2301 *cp++ = '\0'; 2302 } 2303 2304 hints = *pai; 2305 hints.ai_flags = AI_NUMERICHOST; 2306 error = getaddrinfo(addr, NULL, &hints, &res0); 2307 if (error == 0) { 2308 for (res = res0; res; res = res->ai_next) { 2309 /* cover it up */ 2310 res->ai_flags = pai->ai_flags; 2311 2312 if (pai->ai_flags & AI_CANONNAME) 2313 (void)get_canonname(pai, res, canonname); 2314 } 2315 } else 2316 res0 = NULL; 2317 if (res0) { 2318 cur->ai_next = res0; 2319 while (cur && cur->ai_next) 2320 cur = cur->ai_next; 2321 } 2322 2323 if (nextline) { 2324 p = nextline; 2325 goto nextline; 2326 } 2327 2328 done: 2329 return sentinel.ai_next; 2330 } 2331 2332 /*ARGSUSED*/ 2333 static int 2334 _yp_getaddrinfo(void *rv, void *cb_data, va_list ap) 2335 { 2336 struct addrinfo sentinel, *cur; 2337 struct addrinfo *ai = NULL; 2338 char *ypbuf; 2339 int ypbuflen, r; 2340 const char *name; 2341 const struct addrinfo *pai; 2342 char *ypdomain; 2343 2344 if (_yp_check(&ypdomain) == 0) 2345 return NS_UNAVAIL; 2346 2347 name = va_arg(ap, char *); 2348 pai = va_arg(ap, const struct addrinfo *); 2349 2350 memset(&sentinel, 0, sizeof(sentinel)); 2351 cur = &sentinel; 2352 2353 /* hosts.byname is only for IPv4 (Solaris8) */ 2354 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2355 r = yp_match(ypdomain, "hosts.byname", name, 2356 (int)strlen(name), &ypbuf, &ypbuflen); 2357 if (r == 0) { 2358 struct addrinfo ai4; 2359 2360 ai4 = *pai; 2361 ai4.ai_family = AF_INET; 2362 ai = _yphostent(ypbuf, &ai4); 2363 if (ai) { 2364 cur->ai_next = ai; 2365 while (cur && cur->ai_next) 2366 cur = cur->ai_next; 2367 } 2368 free(ypbuf); 2369 } 2370 } 2371 2372 /* ipnodes.byname can hold both IPv4/v6 */ 2373 r = yp_match(ypdomain, "ipnodes.byname", name, 2374 (int)strlen(name), &ypbuf, &ypbuflen); 2375 if (r == 0) { 2376 ai = _yphostent(ypbuf, pai); 2377 if (ai) 2378 cur->ai_next = ai; 2379 free(ypbuf); 2380 } 2381 2382 if (sentinel.ai_next == NULL) { 2383 RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND); 2384 return NS_NOTFOUND; 2385 } 2386 *((struct addrinfo **)rv) = sentinel.ai_next; 2387 return NS_SUCCESS; 2388 } 2389 #endif 2390 2391 /* resolver logic */ 2392 2393 /* 2394 * Formulate a normal query, send, and await answer. 2395 * Returned answer is placed in supplied buffer "answer". 2396 * Perform preliminary check of answer, returning success only 2397 * if no error is indicated and the answer count is nonzero. 2398 * Return the size of the response on success, -1 on error. 2399 * Error number is left in h_errno. 2400 * 2401 * Caller must parse answer and determine whether it answers the question. 2402 */ 2403 static int 2404 res_queryN(const char *name, struct res_target *target, res_state res) 2405 { 2406 u_char *buf; 2407 HEADER *hp; 2408 int n; 2409 u_int oflags; 2410 struct res_target *t; 2411 int rcode; 2412 int ancount; 2413 2414 rcode = NOERROR; 2415 ancount = 0; 2416 2417 buf = malloc(MAXPACKET); 2418 if (!buf) { 2419 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2420 return -1; 2421 } 2422 2423 for (t = target; t; t = t->next) { 2424 int class, type; 2425 u_char *answer; 2426 int anslen; 2427 2428 hp = (HEADER *)(void *)t->answer; 2429 2430 /* make it easier... */ 2431 class = t->qclass; 2432 type = t->qtype; 2433 answer = t->answer; 2434 anslen = t->anslen; 2435 2436 oflags = res->_flags; 2437 2438 again: 2439 hp->rcode = NOERROR; /* default */ 2440 2441 #ifdef DEBUG 2442 if (res->options & RES_DEBUG) 2443 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2444 #endif 2445 2446 n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL, 2447 buf, MAXPACKET); 2448 if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 && 2449 (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U) 2450 n = res_nopt(res, n, buf, MAXPACKET, anslen); 2451 if (n <= 0) { 2452 #ifdef DEBUG 2453 if (res->options & RES_DEBUG) 2454 printf(";; res_query: mkquery failed\n"); 2455 #endif 2456 free(buf); 2457 RES_SET_H_ERRNO(res, NO_RECOVERY); 2458 return (n); 2459 } 2460 n = res_nsend(res, buf, n, answer, anslen); 2461 if (n < 0) { 2462 /* 2463 * if the query choked with EDNS0, retry 2464 * without EDNS0 2465 */ 2466 if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) 2467 != 0U && 2468 ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) { 2469 res->_flags |= RES_F_EDNS0ERR; 2470 if (res->options & RES_DEBUG) 2471 printf(";; res_nquery: retry without EDNS0\n"); 2472 goto again; 2473 } 2474 rcode = hp->rcode; /* record most recent error */ 2475 #ifdef DEBUG 2476 if (res->options & RES_DEBUG) 2477 printf(";; res_query: send error\n"); 2478 #endif 2479 continue; 2480 } 2481 2482 if (n > anslen) 2483 hp->rcode = FORMERR; /* XXX not very informative */ 2484 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2485 rcode = hp->rcode; /* record most recent error */ 2486 #ifdef DEBUG 2487 if (res->options & RES_DEBUG) 2488 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2489 ntohs(hp->ancount)); 2490 #endif 2491 continue; 2492 } 2493 2494 ancount += ntohs(hp->ancount); 2495 2496 t->n = n; 2497 } 2498 2499 free(buf); 2500 2501 if (ancount == 0) { 2502 switch (rcode) { 2503 case NXDOMAIN: 2504 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); 2505 break; 2506 case SERVFAIL: 2507 RES_SET_H_ERRNO(res, TRY_AGAIN); 2508 break; 2509 case NOERROR: 2510 RES_SET_H_ERRNO(res, NO_DATA); 2511 break; 2512 case FORMERR: 2513 case NOTIMP: 2514 case REFUSED: 2515 default: 2516 RES_SET_H_ERRNO(res, NO_RECOVERY); 2517 break; 2518 } 2519 return (-1); 2520 } 2521 return (ancount); 2522 } 2523 2524 /* 2525 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2526 * Return the size of the response on success, -1 on error. 2527 * If enabled, implement search rules until answer or unrecoverable failure 2528 * is detected. Error code, if any, is left in h_errno. 2529 */ 2530 static int 2531 res_searchN(const char *name, struct res_target *target, res_state res) 2532 { 2533 const char *cp, * const *domain; 2534 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2535 u_int dots; 2536 int trailing_dot, ret, saved_herrno; 2537 int got_nodata = 0, got_servfail = 0, root_on_list = 0; 2538 int tried_as_is = 0; 2539 int searched = 0; 2540 char abuf[MAXDNAME]; 2541 2542 errno = 0; 2543 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */ 2544 dots = 0; 2545 for (cp = name; *cp; cp++) 2546 dots += (*cp == '.'); 2547 trailing_dot = 0; 2548 if (cp > name && *--cp == '.') 2549 trailing_dot++; 2550 2551 /* 2552 * if there aren't any dots, it could be a user-level alias 2553 */ 2554 if (!dots && 2555 (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL) 2556 return (res_queryN(cp, target, res)); 2557 2558 /* 2559 * If there are enough dots in the name, let's just give it a 2560 * try 'as is'. The threshold can be set with the "ndots" option. 2561 * Also, query 'as is', if there is a trailing dot in the name. 2562 */ 2563 saved_herrno = -1; 2564 if (dots >= res->ndots || trailing_dot) { 2565 ret = res_querydomainN(name, NULL, target, res); 2566 if (ret > 0 || trailing_dot) 2567 return (ret); 2568 if (errno == ECONNREFUSED) { 2569 RES_SET_H_ERRNO(res, TRY_AGAIN); 2570 return (-1); 2571 } 2572 switch (res->res_h_errno) { 2573 case NO_DATA: 2574 case HOST_NOT_FOUND: 2575 break; 2576 case TRY_AGAIN: 2577 if (hp->rcode == SERVFAIL) 2578 break; 2579 /* FALLTHROUGH */ 2580 default: 2581 return (-1); 2582 } 2583 saved_herrno = res->res_h_errno; 2584 tried_as_is++; 2585 } 2586 2587 /* 2588 * We do at least one level of search if 2589 * - there is no dot and RES_DEFNAME is set, or 2590 * - there is at least one dot, there is no trailing dot, 2591 * and RES_DNSRCH is set. 2592 */ 2593 if ((!dots && (res->options & RES_DEFNAMES)) || 2594 (dots && !trailing_dot && (res->options & RES_DNSRCH))) { 2595 int done = 0; 2596 2597 for (domain = (const char * const *)res->dnsrch; 2598 *domain && !done; 2599 domain++) { 2600 searched = 1; 2601 2602 if (domain[0][0] == '\0' || 2603 (domain[0][0] == '.' && domain[0][1] == '\0')) 2604 root_on_list++; 2605 2606 if (root_on_list && tried_as_is) 2607 continue; 2608 2609 ret = res_querydomainN(name, *domain, target, res); 2610 if (ret > 0) 2611 return (ret); 2612 2613 /* 2614 * If no server present, give up. 2615 * If name isn't found in this domain, 2616 * keep trying higher domains in the search list 2617 * (if that's enabled). 2618 * On a NO_DATA error, keep trying, otherwise 2619 * a wildcard entry of another type could keep us 2620 * from finding this entry higher in the domain. 2621 * If we get some other error (negative answer or 2622 * server failure), then stop searching up, 2623 * but try the input name below in case it's 2624 * fully-qualified. 2625 */ 2626 if (errno == ECONNREFUSED) { 2627 RES_SET_H_ERRNO(res, TRY_AGAIN); 2628 return (-1); 2629 } 2630 2631 switch (res->res_h_errno) { 2632 case NO_DATA: 2633 got_nodata++; 2634 /* FALLTHROUGH */ 2635 case HOST_NOT_FOUND: 2636 /* keep trying */ 2637 break; 2638 case TRY_AGAIN: 2639 got_servfail++; 2640 if (hp->rcode == SERVFAIL) { 2641 /* try next search element, if any */ 2642 break; 2643 } 2644 /* FALLTHROUGH */ 2645 default: 2646 /* anything else implies that we're done */ 2647 done++; 2648 } 2649 /* 2650 * if we got here for some reason other than DNSRCH, 2651 * we only wanted one iteration of the loop, so stop. 2652 */ 2653 if (!(res->options & RES_DNSRCH)) 2654 done++; 2655 } 2656 } 2657 2658 switch (res->res_h_errno) { 2659 case NO_DATA: 2660 case HOST_NOT_FOUND: 2661 break; 2662 case TRY_AGAIN: 2663 if (hp->rcode == SERVFAIL) 2664 break; 2665 /* FALLTHROUGH */ 2666 default: 2667 goto giveup; 2668 } 2669 2670 /* 2671 * If the query has not already been tried as is then try it 2672 * unless RES_NOTLDQUERY is set and there were no dots. 2673 */ 2674 if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) && 2675 !(tried_as_is || root_on_list)) { 2676 ret = res_querydomainN(name, NULL, target, res); 2677 if (ret > 0) 2678 return (ret); 2679 } 2680 2681 /* 2682 * if we got here, we didn't satisfy the search. 2683 * if we did an initial full query, return that query's h_errno 2684 * (note that we wouldn't be here if that query had succeeded). 2685 * else if we ever got a nodata, send that back as the reason. 2686 * else send back meaningless h_errno, that being the one from 2687 * the last DNSRCH we did. 2688 */ 2689 giveup: 2690 if (saved_herrno != -1) 2691 RES_SET_H_ERRNO(res, saved_herrno); 2692 else if (got_nodata) 2693 RES_SET_H_ERRNO(res, NO_DATA); 2694 else if (got_servfail) 2695 RES_SET_H_ERRNO(res, TRY_AGAIN); 2696 return (-1); 2697 } 2698 2699 /* 2700 * Perform a call on res_query on the concatenation of name and domain, 2701 * removing a trailing dot from name if domain is NULL. 2702 */ 2703 static int 2704 res_querydomainN(const char *name, const char *domain, 2705 struct res_target *target, res_state res) 2706 { 2707 char nbuf[MAXDNAME]; 2708 const char *longname = nbuf; 2709 size_t n, d; 2710 2711 #ifdef DEBUG 2712 if (res->options & RES_DEBUG) 2713 printf(";; res_querydomain(%s, %s)\n", 2714 name, domain?domain:"<Nil>"); 2715 #endif 2716 if (domain == NULL) { 2717 /* 2718 * Check for trailing '.'; 2719 * copy without '.' if present. 2720 */ 2721 n = strlen(name); 2722 if (n >= MAXDNAME) { 2723 RES_SET_H_ERRNO(res, NO_RECOVERY); 2724 return (-1); 2725 } 2726 if (n > 0 && name[--n] == '.') { 2727 strncpy(nbuf, name, n); 2728 nbuf[n] = '\0'; 2729 } else 2730 longname = name; 2731 } else { 2732 n = strlen(name); 2733 d = strlen(domain); 2734 if (n + d + 1 >= MAXDNAME) { 2735 RES_SET_H_ERRNO(res, NO_RECOVERY); 2736 return (-1); 2737 } 2738 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2739 } 2740 return (res_queryN(longname, target, res)); 2741 } 2742