1 /* $FreeBSD: src/lib/libc/net/getaddrinfo.c,v 1.87 2008/02/03 19:07:55 ume Exp $ */ 2 /* $DragonFly: src/lib/libc/net/getaddrinfo.c,v 1.9 2008/10/04 22:38:42 swildner Exp $ */ 3 /* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $ */ 4 5 /* 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * "#ifdef FAITH" part is local hack for supporting IPv4-v6 translator. 36 * 37 * Issues to be discussed: 38 * - Return values. There are nonstandard return values defined and used 39 * in the source code. This is because RFC2553 is silent about which error 40 * code must be returned for which situation. 41 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 42 * invalid. current code - SEGV on freeaddrinfo(NULL) 43 * 44 * Note: 45 * - The code filters out AFs that are not supported by the kernel, 46 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 47 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 48 * in ai_flags? 49 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 50 * (1) what should we do against numeric hostname (2) what should we do 51 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 52 * non-loopback address configured? global address configured? 53 * 54 * OS specific notes for freebsd4: 55 * - FreeBSD supported $GAI. The code does not. 56 */ 57 58 #include "namespace.h" 59 #include <sys/types.h> 60 #include <sys/param.h> 61 #include <sys/socket.h> 62 #include <net/if.h> 63 #include <netinet/in.h> 64 #include <sys/queue.h> 65 #ifdef INET6 66 #include <net/if_var.h> 67 #include <sys/sysctl.h> 68 #include <sys/ioctl.h> 69 #include <netinet6/in6_var.h> /* XXX */ 70 #endif 71 #include <arpa/inet.h> 72 #include <arpa/nameser.h> 73 #include <rpc/rpc.h> 74 #include <rpcsvc/yp_prot.h> 75 #include <rpcsvc/ypclnt.h> 76 #include <netdb.h> 77 #include <resolv.h> 78 #include <string.h> 79 #include <stdlib.h> 80 #include <stddef.h> 81 #include <ctype.h> 82 #include <unistd.h> 83 #include <stdio.h> 84 #include <errno.h> 85 86 #include "res_config.h" 87 88 #ifdef DEBUG 89 #include <syslog.h> 90 #endif 91 92 #include <stdarg.h> 93 #include <nsswitch.h> 94 #include "un-namespace.h" 95 #include "libc_private.h" 96 #ifdef NS_CACHING 97 #include "nscache.h" 98 #endif 99 100 #if defined(__KAME__) && defined(INET6) 101 # define FAITH 102 #endif 103 104 #define SUCCESS 0 105 #define ANY 0 106 #define YES 1 107 #define NO 0 108 109 static const char in_addrany[] = { 0, 0, 0, 0 }; 110 static const char in_loopback[] = { 127, 0, 0, 1 }; 111 #ifdef INET6 112 static const char in6_addrany[] = { 113 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 114 }; 115 static const char in6_loopback[] = { 116 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 117 }; 118 #endif 119 120 struct policyqueue { 121 TAILQ_ENTRY(policyqueue) pc_entry; 122 #ifdef INET6 123 struct in6_addrpolicy pc_policy; 124 #endif 125 }; 126 TAILQ_HEAD(policyhead, policyqueue); 127 128 static const struct afd { 129 int a_af; 130 int a_addrlen; 131 socklen_t a_socklen; 132 int a_off; 133 const char *a_addrany; 134 const char *a_loopback; 135 int a_scoped; 136 } afdl [] = { 137 #ifdef INET6 138 #define N_INET6 0 139 {PF_INET6, sizeof(struct in6_addr), 140 sizeof(struct sockaddr_in6), 141 offsetof(struct sockaddr_in6, sin6_addr), 142 in6_addrany, in6_loopback, 1}, 143 #define N_INET 1 144 #else 145 #define N_INET 0 146 #endif 147 {PF_INET, sizeof(struct in_addr), 148 sizeof(struct sockaddr_in), 149 offsetof(struct sockaddr_in, sin_addr), 150 in_addrany, in_loopback, 0}, 151 {0, 0, 0, 0, NULL, NULL, 0}, 152 }; 153 154 struct explore { 155 int e_af; 156 int e_socktype; 157 int e_protocol; 158 const char *e_protostr; 159 int e_wild; 160 #define WILD_AF(ex) ((ex)->e_wild & 0x01) 161 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 162 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 163 }; 164 165 static const struct explore explore[] = { 166 #if 0 167 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 168 #endif 169 #ifdef INET6 170 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 171 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 172 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 173 #endif 174 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 175 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 176 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 177 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 178 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 179 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, 180 { -1, 0, 0, NULL, 0 }, 181 }; 182 183 #ifdef INET6 184 #define PTON_MAX 16 185 #else 186 #define PTON_MAX 4 187 #endif 188 189 #define AIO_SRCFLAG_DEPRECATED 0x1 190 191 struct ai_order { 192 union { 193 struct sockaddr_storage aiou_ss; 194 struct sockaddr aiou_sa; 195 } aio_src_un; 196 #define aio_srcsa aio_src_un.aiou_sa 197 u_int32_t aio_srcflag; 198 int aio_srcscope; 199 int aio_dstscope; 200 struct policyqueue *aio_srcpolicy; 201 struct policyqueue *aio_dstpolicy; 202 struct addrinfo *aio_ai; 203 int aio_matchlen; 204 }; 205 206 static const ns_src default_dns_files[] = { 207 { NSSRC_FILES, NS_SUCCESS }, 208 { NSSRC_DNS, NS_SUCCESS }, 209 { 0 } 210 }; 211 212 struct res_target { 213 struct res_target *next; 214 const char *name; /* domain name */ 215 int qclass, qtype; /* class and type of query */ 216 u_char *answer; /* buffer to put answer */ 217 int anslen; /* size of answer buffer */ 218 int n; /* result length */ 219 }; 220 221 #define MAXPACKET (64*1024) 222 223 typedef union { 224 HEADER hdr; 225 u_char buf[MAXPACKET]; 226 } querybuf; 227 228 static int str2number(const char *, int *); 229 static int explore_null(const struct addrinfo *, 230 const char *, struct addrinfo **); 231 static int explore_numeric(const struct addrinfo *, const char *, 232 const char *, struct addrinfo **, const char *); 233 static int explore_numeric_scope(const struct addrinfo *, const char *, 234 const char *, struct addrinfo **); 235 static int get_canonname(const struct addrinfo *, 236 struct addrinfo *, const char *); 237 static struct addrinfo *get_ai(const struct addrinfo *, 238 const struct afd *, const char *); 239 static int get_portmatch(const struct addrinfo *, const char *); 240 static int get_port(struct addrinfo *, const char *, int); 241 static const struct afd *find_afd(int); 242 static int addrconfig(struct addrinfo *); 243 static void set_source(struct ai_order *, struct policyhead *); 244 static int comp_dst(const void *, const void *); 245 #ifdef INET6 246 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 247 #endif 248 static int gai_addr2scopetype(struct sockaddr *); 249 250 static int explore_fqdn(const struct addrinfo *, const char *, 251 const char *, struct addrinfo **); 252 253 static int reorder(struct addrinfo *); 254 static int get_addrselectpolicy(struct policyhead *); 255 static void free_addrselectpolicy(struct policyhead *); 256 static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 257 struct policyhead *); 258 static int matchlen(struct sockaddr *, struct sockaddr *); 259 260 static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 261 const struct addrinfo *, res_state); 262 #if defined(RESOLVSORT) 263 static int addr4sort(struct addrinfo *, res_state); 264 #endif 265 static int _dns_getaddrinfo(void *, void *, va_list); 266 static void _sethtent(FILE **); 267 static void _endhtent(FILE **); 268 static struct addrinfo *_gethtent(FILE **, const char *, 269 const struct addrinfo *); 270 static int _files_getaddrinfo(void *, void *, va_list); 271 #ifdef YP 272 static struct addrinfo *_yphostent(char *, const struct addrinfo *); 273 static int _yp_getaddrinfo(void *, void *, va_list); 274 #endif 275 #ifdef NS_CACHING 276 static int addrinfo_id_func(char *, size_t *, va_list, void *); 277 static int addrinfo_marshal_func(char *, size_t *, void *, va_list, 278 void *); 279 static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, 280 void *); 281 #endif 282 283 static int res_queryN(const char *, struct res_target *, res_state); 284 static int res_searchN(const char *, struct res_target *, res_state); 285 static int res_querydomainN(const char *, const char *, 286 struct res_target *, res_state); 287 288 /* XXX macros that make external reference is BAD. */ 289 290 #define GET_AI(ai, afd, addr) \ 291 do { \ 292 /* external reference: pai, error, and label free */ \ 293 (ai) = get_ai(pai, (afd), (addr)); \ 294 if ((ai) == NULL) { \ 295 error = EAI_MEMORY; \ 296 goto free; \ 297 } \ 298 } while (/*CONSTCOND*/0) 299 300 #define GET_PORT(ai, serv) \ 301 do { \ 302 /* external reference: error and label free */ \ 303 error = get_port((ai), (serv), 0); \ 304 if (error != 0) \ 305 goto free; \ 306 } while (/*CONSTCOND*/0) 307 308 #define GET_CANONNAME(ai, str) \ 309 do { \ 310 /* external reference: pai, error and label free */ \ 311 error = get_canonname(pai, (ai), (str)); \ 312 if (error != 0) \ 313 goto free; \ 314 } while (/*CONSTCOND*/0) 315 316 #define ERR(err) \ 317 do { \ 318 /* external reference: error, and label bad */ \ 319 error = (err); \ 320 goto bad; \ 321 /*NOTREACHED*/ \ 322 } while (/*CONSTCOND*/0) 323 324 #define MATCH_FAMILY(x, y, w) \ 325 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 326 #define MATCH(x, y, w) \ 327 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 328 329 void 330 freeaddrinfo(struct addrinfo *ai) 331 { 332 struct addrinfo *next; 333 334 do { 335 next = ai->ai_next; 336 if (ai->ai_canonname) 337 free(ai->ai_canonname); 338 /* no need to free(ai->ai_addr) */ 339 free(ai); 340 ai = next; 341 } while (ai); 342 } 343 344 static int 345 str2number(const char *p, int *portp) 346 { 347 char *ep; 348 unsigned long v; 349 350 if (*p == '\0') 351 return -1; 352 ep = NULL; 353 errno = 0; 354 v = strtoul(p, &ep, 10); 355 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) { 356 *portp = v; 357 return 0; 358 } else 359 return -1; 360 } 361 362 int 363 getaddrinfo(const char *hostname, const char *servname, 364 const struct addrinfo *hints, struct addrinfo **res) 365 { 366 struct addrinfo sentinel; 367 struct addrinfo *cur; 368 int error = 0; 369 struct addrinfo ai; 370 struct addrinfo ai0; 371 struct addrinfo *pai; 372 const struct explore *ex; 373 int numeric = 0; 374 375 memset(&sentinel, 0, sizeof(sentinel)); 376 cur = &sentinel; 377 pai = &ai; 378 pai->ai_flags = 0; 379 pai->ai_family = PF_UNSPEC; 380 pai->ai_socktype = ANY; 381 pai->ai_protocol = ANY; 382 pai->ai_addrlen = 0; 383 pai->ai_canonname = NULL; 384 pai->ai_addr = NULL; 385 pai->ai_next = NULL; 386 387 if (hostname == NULL && servname == NULL) 388 return EAI_NONAME; 389 if (hints) { 390 /* error check for hints */ 391 if (hints->ai_addrlen || hints->ai_canonname || 392 hints->ai_addr || hints->ai_next) 393 ERR(EAI_BADHINTS); /* xxx */ 394 if (hints->ai_flags & ~AI_MASK) 395 ERR(EAI_BADFLAGS); 396 switch (hints->ai_family) { 397 case PF_UNSPEC: 398 case PF_INET: 399 #ifdef INET6 400 case PF_INET6: 401 #endif 402 break; 403 default: 404 ERR(EAI_FAMILY); 405 } 406 memcpy(pai, hints, sizeof(*pai)); 407 408 /* 409 * if both socktype/protocol are specified, check if they 410 * are meaningful combination. 411 */ 412 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 413 for (ex = explore; ex->e_af >= 0; ex++) { 414 if (pai->ai_family != ex->e_af) 415 continue; 416 if (ex->e_socktype == ANY) 417 continue; 418 if (ex->e_protocol == ANY) 419 continue; 420 if (pai->ai_socktype == ex->e_socktype && 421 pai->ai_protocol != ex->e_protocol) { 422 ERR(EAI_BADHINTS); 423 } 424 } 425 } 426 } 427 428 /* 429 * check for special cases. (1) numeric servname is disallowed if 430 * socktype/protocol are left unspecified. (2) servname is disallowed 431 * for raw and other inet{,6} sockets. 432 */ 433 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 434 #ifdef PF_INET6 435 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 436 #endif 437 ) { 438 ai0 = *pai; /* backup *pai */ 439 440 if (pai->ai_family == PF_UNSPEC) { 441 #ifdef PF_INET6 442 pai->ai_family = PF_INET6; 443 #else 444 pai->ai_family = PF_INET; 445 #endif 446 } 447 error = get_portmatch(pai, servname); 448 if (error) 449 ERR(error); 450 451 *pai = ai0; 452 } 453 454 ai0 = *pai; 455 456 /* NULL hostname, or numeric hostname */ 457 for (ex = explore; ex->e_af >= 0; ex++) { 458 *pai = ai0; 459 460 /* PF_UNSPEC entries are prepared for DNS queries only */ 461 if (ex->e_af == PF_UNSPEC) 462 continue; 463 464 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 465 continue; 466 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 467 continue; 468 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 469 continue; 470 471 if (pai->ai_family == PF_UNSPEC) 472 pai->ai_family = ex->e_af; 473 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 474 pai->ai_socktype = ex->e_socktype; 475 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 476 pai->ai_protocol = ex->e_protocol; 477 478 if (hostname == NULL) 479 error = explore_null(pai, servname, &cur->ai_next); 480 else 481 error = explore_numeric_scope(pai, hostname, servname, 482 &cur->ai_next); 483 484 if (error) 485 goto free; 486 487 while (cur && cur->ai_next) 488 cur = cur->ai_next; 489 } 490 491 /* 492 * XXX 493 * If numreic representation of AF1 can be interpreted as FQDN 494 * representation of AF2, we need to think again about the code below. 495 */ 496 if (sentinel.ai_next) { 497 numeric = 1; 498 goto good; 499 } 500 501 if (hostname == NULL) 502 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 503 if (pai->ai_flags & AI_NUMERICHOST) 504 ERR(EAI_NONAME); 505 506 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 507 ERR(EAI_FAIL); 508 509 /* 510 * hostname as alphabetical name. 511 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 512 * outer loop by AFs. 513 */ 514 for (ex = explore; ex->e_af >= 0; ex++) { 515 *pai = ai0; 516 517 /* require exact match for family field */ 518 if (pai->ai_family != ex->e_af) 519 continue; 520 521 if (!MATCH(pai->ai_socktype, ex->e_socktype, 522 WILD_SOCKTYPE(ex))) { 523 continue; 524 } 525 if (!MATCH(pai->ai_protocol, ex->e_protocol, 526 WILD_PROTOCOL(ex))) { 527 continue; 528 } 529 530 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 531 pai->ai_socktype = ex->e_socktype; 532 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 533 pai->ai_protocol = ex->e_protocol; 534 535 error = explore_fqdn(pai, hostname, servname, &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 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, 1103 const char *canonname) 1104 { 1105 const struct afd *afd; 1106 struct addrinfo *ai; 1107 int error; 1108 char pton[PTON_MAX]; 1109 1110 *res = NULL; 1111 ai = NULL; 1112 1113 /* 1114 * if the servname does not match socktype/protocol, ignore it. 1115 */ 1116 if (get_portmatch(pai, servname) != 0) 1117 return 0; 1118 1119 afd = find_afd(pai->ai_family); 1120 if (afd == NULL) 1121 return 0; 1122 1123 switch (afd->a_af) { 1124 case AF_INET: 1125 /* 1126 * RFC3493 requires getaddrinfo() to accept AF_INET formats 1127 * that are accepted by inet_addr() and its family. The 1128 * accepted forms includes the "classful" one, which inet_pton 1129 * does not accept. So we need to separate the case for 1130 * AF_INET. 1131 */ 1132 if (inet_aton(hostname, (struct in_addr *)pton) != 1) 1133 return 0; 1134 break; 1135 default: 1136 if (inet_pton(afd->a_af, hostname, pton) != 1) 1137 return 0; 1138 break; 1139 } 1140 1141 if (pai->ai_family == afd->a_af) { 1142 GET_AI(ai, afd, pton); 1143 GET_PORT(ai, servname); 1144 if ((pai->ai_flags & AI_CANONNAME)) { 1145 /* 1146 * Set the numeric address itself as the canonical 1147 * name, based on a clarification in RFC3493. 1148 */ 1149 GET_CANONNAME(ai, canonname); 1150 } 1151 } else { 1152 /* 1153 * XXX: This should not happen since we already matched the AF 1154 * by find_afd. 1155 */ 1156 ERR(EAI_FAMILY); 1157 } 1158 1159 *res = ai; 1160 return 0; 1161 1162 free: 1163 bad: 1164 if (ai != NULL) 1165 freeaddrinfo(ai); 1166 return error; 1167 } 1168 1169 /* 1170 * numeric hostname with scope 1171 */ 1172 static int 1173 explore_numeric_scope(const struct addrinfo *pai, const char *hostname, 1174 const char *servname, struct addrinfo **res) 1175 { 1176 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 1177 return explore_numeric(pai, hostname, servname, res, hostname); 1178 #else 1179 const struct afd *afd; 1180 struct addrinfo *cur; 1181 int error; 1182 char *cp, *hostname2 = NULL, *scope, *addr; 1183 struct sockaddr_in6 *sin6; 1184 1185 /* 1186 * if the servname does not match socktype/protocol, ignore it. 1187 */ 1188 if (get_portmatch(pai, servname) != 0) 1189 return 0; 1190 1191 afd = find_afd(pai->ai_family); 1192 if (afd == NULL) 1193 return 0; 1194 1195 if (!afd->a_scoped) 1196 return explore_numeric(pai, hostname, servname, res, hostname); 1197 1198 cp = strchr(hostname, SCOPE_DELIMITER); 1199 if (cp == NULL) 1200 return explore_numeric(pai, hostname, servname, res, hostname); 1201 1202 /* 1203 * Handle special case of <scoped_address><delimiter><scope id> 1204 */ 1205 hostname2 = strdup(hostname); 1206 if (hostname2 == NULL) 1207 return EAI_MEMORY; 1208 /* terminate at the delimiter */ 1209 hostname2[cp - hostname] = '\0'; 1210 addr = hostname2; 1211 scope = cp + 1; 1212 1213 error = explore_numeric(pai, addr, servname, res, hostname); 1214 if (error == 0) { 1215 u_int32_t scopeid; 1216 1217 for (cur = *res; cur; cur = cur->ai_next) { 1218 if (cur->ai_family != AF_INET6) 1219 continue; 1220 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1221 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1222 free(hostname2); 1223 return(EAI_NONAME); /* XXX: is return OK? */ 1224 } 1225 sin6->sin6_scope_id = scopeid; 1226 } 1227 } 1228 1229 free(hostname2); 1230 1231 return error; 1232 #endif 1233 } 1234 1235 static int 1236 get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) 1237 { 1238 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1239 ai->ai_canonname = strdup(str); 1240 if (ai->ai_canonname == NULL) 1241 return EAI_MEMORY; 1242 } 1243 return 0; 1244 } 1245 1246 static struct addrinfo * 1247 get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) 1248 { 1249 char *p; 1250 struct addrinfo *ai; 1251 #ifdef FAITH 1252 struct in6_addr faith_prefix; 1253 char *fp_str; 1254 int translate = 0; 1255 #endif 1256 1257 #ifdef FAITH 1258 /* 1259 * Transfrom an IPv4 addr into a special IPv6 addr format for 1260 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1261 * 1262 * +-----------------------------------+------------+ 1263 * | faith prefix part (12 bytes) | embedded | 1264 * | | IPv4 addr part (4 bytes) 1265 * +-----------------------------------+------------+ 1266 * 1267 * faith prefix part is specified as ascii IPv6 addr format 1268 * in environmental variable GAI. 1269 * For FAITH to work correctly, routing to faith prefix must be 1270 * setup toward a machine where a FAITH daemon operates. 1271 * Also, the machine must enable some mechanizm 1272 * (e.g. faith interface hack) to divert those packet with 1273 * faith prefixed destination addr to user-land FAITH daemon. 1274 */ 1275 fp_str = getenv("GAI"); 1276 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1277 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1278 u_int32_t v4a; 1279 u_int8_t v4a_top; 1280 1281 memcpy(&v4a, addr, sizeof v4a); 1282 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1283 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1284 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1285 afd = &afdl[N_INET6]; 1286 memcpy(&faith_prefix.s6_addr[12], addr, 1287 sizeof(struct in_addr)); 1288 translate = 1; 1289 } 1290 } 1291 #endif 1292 1293 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1294 + (afd->a_socklen)); 1295 if (ai == NULL) 1296 return NULL; 1297 1298 memcpy(ai, pai, sizeof(struct addrinfo)); 1299 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1300 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1301 ai->ai_addr->sa_len = afd->a_socklen; 1302 ai->ai_addrlen = afd->a_socklen; 1303 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1304 p = (char *)(void *)(ai->ai_addr); 1305 #ifdef FAITH 1306 if (translate == 1) 1307 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1308 else 1309 #endif 1310 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1311 return ai; 1312 } 1313 1314 static int 1315 get_portmatch(const struct addrinfo *ai, const char *servname) 1316 { 1317 1318 /* get_port does not touch first argument when matchonly == 1. */ 1319 /* LINTED const cast */ 1320 return get_port((struct addrinfo *)ai, servname, 1); 1321 } 1322 1323 static int 1324 get_port(struct addrinfo *ai, const char *servname, int matchonly) 1325 { 1326 const char *proto; 1327 struct servent *sp; 1328 int port, error; 1329 int allownumeric; 1330 1331 if (servname == NULL) 1332 return 0; 1333 switch (ai->ai_family) { 1334 case AF_INET: 1335 #ifdef AF_INET6 1336 case AF_INET6: 1337 #endif 1338 break; 1339 default: 1340 return 0; 1341 } 1342 1343 switch (ai->ai_socktype) { 1344 case SOCK_RAW: 1345 return EAI_SERVICE; 1346 case SOCK_DGRAM: 1347 case SOCK_STREAM: 1348 allownumeric = 1; 1349 break; 1350 case ANY: 1351 allownumeric = 0; 1352 break; 1353 default: 1354 return EAI_SOCKTYPE; 1355 } 1356 1357 error = str2number(servname, &port); 1358 if (error == 0) { 1359 if (!allownumeric) 1360 return EAI_SERVICE; 1361 if (port < 0 || port > 65535) 1362 return EAI_SERVICE; 1363 port = htons(port); 1364 } else { 1365 if (ai->ai_flags & AI_NUMERICSERV) 1366 return EAI_NONAME; 1367 switch (ai->ai_socktype) { 1368 case SOCK_DGRAM: 1369 proto = "udp"; 1370 break; 1371 case SOCK_STREAM: 1372 proto = "tcp"; 1373 break; 1374 default: 1375 proto = NULL; 1376 break; 1377 } 1378 1379 if ((sp = getservbyname(servname, proto)) == NULL) 1380 return EAI_SERVICE; 1381 port = sp->s_port; 1382 } 1383 1384 if (!matchonly) { 1385 switch (ai->ai_family) { 1386 case AF_INET: 1387 ((struct sockaddr_in *)(void *) 1388 ai->ai_addr)->sin_port = port; 1389 break; 1390 #ifdef INET6 1391 case AF_INET6: 1392 ((struct sockaddr_in6 *)(void *) 1393 ai->ai_addr)->sin6_port = port; 1394 break; 1395 #endif 1396 } 1397 } 1398 1399 return 0; 1400 } 1401 1402 static const struct afd * 1403 find_afd(int af) 1404 { 1405 const struct afd *afd; 1406 1407 if (af == PF_UNSPEC) 1408 return NULL; 1409 for (afd = afdl; afd->a_af; afd++) { 1410 if (afd->a_af == af) 1411 return afd; 1412 } 1413 return NULL; 1414 } 1415 1416 /* 1417 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1418 * will take care of it. 1419 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1420 * if the code is right or not. 1421 * 1422 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1423 * _dns_getaddrinfo. 1424 */ 1425 static int 1426 addrconfig(struct addrinfo *pai) 1427 { 1428 int s, af; 1429 1430 /* 1431 * TODO: 1432 * Note that implementation dependent test for address 1433 * configuration should be done everytime called 1434 * (or apropriate interval), 1435 * because addresses will be dynamically assigned or deleted. 1436 */ 1437 af = pai->ai_family; 1438 if (af == AF_UNSPEC) { 1439 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1440 af = AF_INET; 1441 else { 1442 _close(s); 1443 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1444 af = AF_INET6; 1445 else 1446 _close(s); 1447 } 1448 } 1449 if (af != AF_UNSPEC) { 1450 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1451 return 0; 1452 _close(s); 1453 } 1454 pai->ai_family = af; 1455 return 1; 1456 } 1457 1458 #ifdef INET6 1459 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1460 static int 1461 ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid) 1462 { 1463 u_long lscopeid; 1464 struct in6_addr *a6; 1465 char *ep; 1466 1467 a6 = &sin6->sin6_addr; 1468 1469 /* empty scopeid portion is invalid */ 1470 if (*scope == '\0') 1471 return -1; 1472 1473 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1474 /* 1475 * We currently assume a one-to-one mapping between links 1476 * and interfaces, so we simply use interface indices for 1477 * like-local scopes. 1478 */ 1479 *scopeid = if_nametoindex(scope); 1480 if (*scopeid == 0) 1481 goto trynumeric; 1482 return 0; 1483 } 1484 1485 /* still unclear about literal, allow numeric only - placeholder */ 1486 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1487 goto trynumeric; 1488 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1489 goto trynumeric; 1490 else 1491 goto trynumeric; /* global */ 1492 1493 /* try to convert to a numeric id as a last resort */ 1494 trynumeric: 1495 errno = 0; 1496 lscopeid = strtoul(scope, &ep, 10); 1497 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1498 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1499 return 0; 1500 else 1501 return -1; 1502 } 1503 #endif 1504 1505 1506 #ifdef NS_CACHING 1507 static int 1508 addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap, 1509 void *cache_mdata) 1510 { 1511 res_state statp; 1512 u_long res_options; 1513 1514 const int op_id = 0; /* identifies the getaddrinfo for the cache */ 1515 char *hostname; 1516 struct addrinfo *hints; 1517 1518 char *p; 1519 int ai_flags, ai_family, ai_socktype, ai_protocol; 1520 size_t desired_size, size; 1521 1522 statp = __res_state(); 1523 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES | 1524 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6); 1525 1526 hostname = va_arg(ap, char *); 1527 hints = va_arg(ap, struct addrinfo *); 1528 1529 desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4; 1530 if (hostname != NULL) { 1531 size = strlen(hostname); 1532 desired_size += size + 1; 1533 } else 1534 size = 0; 1535 1536 if (desired_size > *buffer_size) { 1537 *buffer_size = desired_size; 1538 return (NS_RETURN); 1539 } 1540 1541 if (hints == NULL) 1542 ai_flags = ai_family = ai_socktype = ai_protocol = 0; 1543 else { 1544 ai_flags = hints->ai_flags; 1545 ai_family = hints->ai_family; 1546 ai_socktype = hints->ai_socktype; 1547 ai_protocol = hints->ai_protocol; 1548 } 1549 1550 p = buffer; 1551 memcpy(p, &res_options, sizeof(res_options)); 1552 p += sizeof(res_options); 1553 1554 memcpy(p, &op_id, sizeof(int)); 1555 p += sizeof(int); 1556 1557 memcpy(p, &ai_flags, sizeof(int)); 1558 p += sizeof(int); 1559 1560 memcpy(p, &ai_family, sizeof(int)); 1561 p += sizeof(int); 1562 1563 memcpy(p, &ai_socktype, sizeof(int)); 1564 p += sizeof(int); 1565 1566 memcpy(p, &ai_protocol, sizeof(int)); 1567 p += sizeof(int); 1568 1569 if (hostname != NULL) 1570 memcpy(p, hostname, size); 1571 1572 *buffer_size = desired_size; 1573 return (NS_SUCCESS); 1574 } 1575 1576 static int 1577 addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval, 1578 va_list ap, void *cache_mdata) 1579 { 1580 struct addrinfo *ai, *cai; 1581 char *p; 1582 size_t desired_size, size, ai_size; 1583 1584 ai = *((struct addrinfo **)retval); 1585 1586 desired_size = sizeof(size_t); 1587 ai_size = 0; 1588 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1589 desired_size += sizeof(struct addrinfo) + cai->ai_addrlen; 1590 if (cai->ai_canonname != NULL) 1591 desired_size += sizeof(size_t) + 1592 strlen(cai->ai_canonname); 1593 ++ai_size; 1594 } 1595 1596 if (desired_size > *buffer_size) { 1597 /* this assignment is here for future use */ 1598 errno = ERANGE; 1599 *buffer_size = desired_size; 1600 return (NS_RETURN); 1601 } 1602 1603 memset(buffer, 0, desired_size); 1604 p = buffer; 1605 1606 memcpy(p, &ai_size, sizeof(size_t)); 1607 p += sizeof(size_t); 1608 for (cai = ai; cai != NULL; cai = cai->ai_next) { 1609 memcpy(p, cai, sizeof(struct addrinfo)); 1610 p += sizeof(struct addrinfo); 1611 1612 memcpy(p, cai->ai_addr, cai->ai_addrlen); 1613 p += cai->ai_addrlen; 1614 1615 if (cai->ai_canonname != NULL) { 1616 size = strlen(cai->ai_canonname); 1617 memcpy(p, &size, sizeof(size_t)); 1618 p += sizeof(size_t); 1619 1620 memcpy(p, cai->ai_canonname, size); 1621 p += size; 1622 } 1623 } 1624 1625 return (NS_SUCCESS); 1626 } 1627 1628 static int 1629 addrinfo_unmarshal_func(char *buffer, size_t buffer_size, void *retval, 1630 va_list ap, void *cache_mdata) 1631 { 1632 struct addrinfo new_ai, *result, *sentinel, *lasts; 1633 1634 char *p; 1635 size_t ai_size, ai_i, size; 1636 1637 p = buffer; 1638 memcpy(&ai_size, p, sizeof(size_t)); 1639 p += sizeof(size_t); 1640 1641 result = NULL; 1642 lasts = NULL; 1643 for (ai_i = 0; ai_i < ai_size; ++ai_i) { 1644 memcpy(&new_ai, p, sizeof(struct addrinfo)); 1645 p += sizeof(struct addrinfo); 1646 size = new_ai.ai_addrlen + sizeof(struct addrinfo) + 1647 _ALIGNBYTES; 1648 1649 sentinel = (struct addrinfo *)malloc(size); 1650 memset(sentinel, 0, size); 1651 1652 memcpy(sentinel, &new_ai, sizeof(struct addrinfo)); 1653 sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel + 1654 sizeof(struct addrinfo)); 1655 1656 memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen); 1657 p += new_ai.ai_addrlen; 1658 1659 if (new_ai.ai_canonname != NULL) { 1660 memcpy(&size, p, sizeof(size_t)); 1661 p += sizeof(size_t); 1662 1663 sentinel->ai_canonname = (char *)malloc(size + 1); 1664 memset(sentinel->ai_canonname, 0, size + 1); 1665 1666 memcpy(sentinel->ai_canonname, p, size); 1667 p += size; 1668 } 1669 1670 if (result == NULL) { 1671 result = sentinel; 1672 lasts = sentinel; 1673 } else { 1674 lasts->ai_next = sentinel; 1675 lasts = sentinel; 1676 } 1677 } 1678 1679 *((struct addrinfo **)retval) = result; 1680 return (NS_SUCCESS); 1681 } 1682 #endif /* NS_CACHING */ 1683 1684 /* 1685 * FQDN hostname, DNS lookup 1686 */ 1687 static int 1688 explore_fqdn(const struct addrinfo *pai, const char *hostname, 1689 const char *servname, struct addrinfo **res) 1690 { 1691 struct addrinfo *result; 1692 struct addrinfo *cur; 1693 int error = 0; 1694 1695 #ifdef NS_CACHING 1696 static const nss_cache_info cache_info = 1697 NS_COMMON_CACHE_INFO_INITIALIZER( 1698 hosts, NULL, addrinfo_id_func, addrinfo_marshal_func, 1699 addrinfo_unmarshal_func); 1700 #endif 1701 static const ns_dtab dtab[] = { 1702 NS_FILES_CB(_files_getaddrinfo, NULL) 1703 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1704 NS_NIS_CB(_yp_getaddrinfo, NULL) 1705 #ifdef NS_CACHING 1706 NS_CACHE_CB(&cache_info) 1707 #endif 1708 { 0 } 1709 }; 1710 1711 result = NULL; 1712 1713 /* 1714 * if the servname does not match socktype/protocol, ignore it. 1715 */ 1716 if (get_portmatch(pai, servname) != 0) 1717 return 0; 1718 1719 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1720 default_dns_files, hostname, pai)) { 1721 case NS_TRYAGAIN: 1722 error = EAI_AGAIN; 1723 goto free; 1724 case NS_UNAVAIL: 1725 error = EAI_FAIL; 1726 goto free; 1727 case NS_NOTFOUND: 1728 error = EAI_NONAME; 1729 goto free; 1730 case NS_SUCCESS: 1731 error = 0; 1732 for (cur = result; cur; cur = cur->ai_next) { 1733 GET_PORT(cur, servname); 1734 /* canonname should be filled already */ 1735 } 1736 break; 1737 } 1738 1739 *res = result; 1740 1741 return 0; 1742 1743 free: 1744 if (result) 1745 freeaddrinfo(result); 1746 return error; 1747 } 1748 1749 #ifdef DEBUG 1750 static const char AskedForGot[] = 1751 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1752 #endif 1753 1754 static struct addrinfo * 1755 getanswer(const querybuf *answer, int anslen, const char *qname, int qtype, 1756 const struct addrinfo *pai, res_state res) 1757 { 1758 struct addrinfo sentinel, *cur; 1759 struct addrinfo ai; 1760 const struct afd *afd; 1761 char *canonname; 1762 const HEADER *hp; 1763 const u_char *cp; 1764 int n; 1765 const u_char *eom; 1766 char *bp, *ep; 1767 int type, class, ancount, qdcount; 1768 int haveanswer, had_error; 1769 char tbuf[MAXDNAME]; 1770 int (*name_ok)(const char *); 1771 char hostbuf[8*1024]; 1772 1773 memset(&sentinel, 0, sizeof(sentinel)); 1774 cur = &sentinel; 1775 1776 canonname = NULL; 1777 eom = answer->buf + anslen; 1778 switch (qtype) { 1779 case T_A: 1780 case T_AAAA: 1781 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1782 name_ok = res_hnok; 1783 break; 1784 default: 1785 return (NULL); /* XXX should be abort(); */ 1786 } 1787 /* 1788 * find first satisfactory answer 1789 */ 1790 hp = &answer->hdr; 1791 ancount = ntohs(hp->ancount); 1792 qdcount = ntohs(hp->qdcount); 1793 bp = hostbuf; 1794 ep = hostbuf + sizeof hostbuf; 1795 cp = answer->buf + HFIXEDSZ; 1796 if (qdcount != 1) { 1797 RES_SET_H_ERRNO(res, NO_RECOVERY); 1798 return (NULL); 1799 } 1800 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1801 if ((n < 0) || !(*name_ok)(bp)) { 1802 RES_SET_H_ERRNO(res, NO_RECOVERY); 1803 return (NULL); 1804 } 1805 cp += n + QFIXEDSZ; 1806 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1807 /* res_send() has already verified that the query name is the 1808 * same as the one we sent; this just gets the expanded name 1809 * (i.e., with the succeeding search-domain tacked on). 1810 */ 1811 n = strlen(bp) + 1; /* for the \0 */ 1812 if (n >= MAXHOSTNAMELEN) { 1813 RES_SET_H_ERRNO(res, NO_RECOVERY); 1814 return (NULL); 1815 } 1816 canonname = bp; 1817 bp += n; 1818 /* The qname can be abbreviated, but h_name is now absolute. */ 1819 qname = canonname; 1820 } 1821 haveanswer = 0; 1822 had_error = 0; 1823 while (ancount-- > 0 && cp < eom && !had_error) { 1824 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1825 if ((n < 0) || !(*name_ok)(bp)) { 1826 had_error++; 1827 continue; 1828 } 1829 cp += n; /* name */ 1830 type = _getshort(cp); 1831 cp += INT16SZ; /* type */ 1832 class = _getshort(cp); 1833 cp += INT16SZ + INT32SZ; /* class, TTL */ 1834 n = _getshort(cp); 1835 cp += INT16SZ; /* len */ 1836 if (class != C_IN) { 1837 /* XXX - debug? syslog? */ 1838 cp += n; 1839 continue; /* XXX - had_error++ ? */ 1840 } 1841 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1842 type == T_CNAME) { 1843 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1844 if ((n < 0) || !(*name_ok)(tbuf)) { 1845 had_error++; 1846 continue; 1847 } 1848 cp += n; 1849 /* Get canonical name. */ 1850 n = strlen(tbuf) + 1; /* for the \0 */ 1851 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1852 had_error++; 1853 continue; 1854 } 1855 strlcpy(bp, tbuf, ep - bp); 1856 canonname = bp; 1857 bp += n; 1858 continue; 1859 } 1860 if (qtype == T_ANY) { 1861 if (!(type == T_A || type == T_AAAA)) { 1862 cp += n; 1863 continue; 1864 } 1865 } else if (type != qtype) { 1866 #ifdef DEBUG 1867 if (type != T_KEY && type != T_SIG) 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 get_canonname(pai, sentinel.ai_next, qname); 1950 else 1951 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 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 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