1 /* $FreeBSD: src/lib/libc/net/getaddrinfo.c,v 1.87 2008/02/03 19:07:55 ume Exp $ */ 2 /* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * "#ifdef FAITH" part is local hack for supporting IPv4-v6 translator. 35 * 36 * Issues to be discussed: 37 * - Return values. There are nonstandard return values defined and used 38 * in the source code. This is because RFC2553 is silent about which error 39 * code must be returned for which situation. 40 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 41 * invalid. current code - SEGV on freeaddrinfo(NULL) 42 * 43 * Note: 44 * - The code filters out AFs that are not supported by the kernel, 45 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 46 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 47 * in ai_flags? 48 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 49 * (1) what should we do against numeric hostname (2) what should we do 50 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 51 * non-loopback address configured? global address configured? 52 * 53 * OS specific notes for freebsd4: 54 * - FreeBSD supported $GAI. The code does not. 55 */ 56 57 #include "namespace.h" 58 #include <sys/types.h> 59 #include <sys/param.h> 60 #include <sys/socket.h> 61 #include <net/if.h> 62 #include <netinet/in.h> 63 #include <sys/queue.h> 64 #ifdef INET6 65 #include <net/if_var.h> 66 #include <sys/sysctl.h> 67 #include <sys/ioctl.h> 68 #include <netinet6/in6_var.h> /* XXX */ 69 #endif 70 #include <arpa/inet.h> 71 #include <arpa/nameser.h> 72 #include <rpc/rpc.h> 73 #include <rpcsvc/yp_prot.h> 74 #include <rpcsvc/ypclnt.h> 75 #include <netdb.h> 76 #include <resolv.h> 77 #include <string.h> 78 #include <stdlib.h> 79 #include <stddef.h> 80 #include <ctype.h> 81 #include <unistd.h> 82 #include <stdio.h> 83 #include <errno.h> 84 85 #include "res_config.h" 86 87 #ifdef DEBUG 88 #include <syslog.h> 89 #endif 90 91 #include <stdarg.h> 92 #include <nsswitch.h> 93 #include "un-namespace.h" 94 #include "libc_private.h" 95 #ifdef NS_CACHING 96 #include "nscache.h" 97 #endif 98 99 #if defined(__KAME__) && defined(INET6) 100 # define FAITH 101 #endif 102 103 #define SUCCESS 0 104 #define ANY 0 105 #define YES 1 106 #define NO 0 107 108 static const char in_addrany[] = { 0, 0, 0, 0 }; 109 static const char in_loopback[] = { 127, 0, 0, 1 }; 110 #ifdef INET6 111 static const char in6_addrany[] = { 112 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 113 }; 114 static const char in6_loopback[] = { 115 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 116 }; 117 #endif 118 119 struct policyqueue { 120 TAILQ_ENTRY(policyqueue) pc_entry; 121 #ifdef INET6 122 struct in6_addrpolicy pc_policy; 123 #endif 124 }; 125 TAILQ_HEAD(policyhead, policyqueue); 126 127 static const struct afd { 128 int a_af; 129 int a_addrlen; 130 socklen_t a_socklen; 131 int a_off; 132 const char *a_addrany; 133 const char *a_loopback; 134 int a_scoped; 135 } afdl [] = { 136 #ifdef INET6 137 #define N_INET6 0 138 {PF_INET6, sizeof(struct in6_addr), 139 sizeof(struct sockaddr_in6), 140 offsetof(struct sockaddr_in6, sin6_addr), 141 in6_addrany, in6_loopback, 1}, 142 #define N_INET 1 143 #else 144 #define N_INET 0 145 #endif 146 {PF_INET, sizeof(struct in_addr), 147 sizeof(struct sockaddr_in), 148 offsetof(struct sockaddr_in, sin_addr), 149 in_addrany, in_loopback, 0}, 150 {0, 0, 0, 0, NULL, NULL, 0}, 151 }; 152 153 struct explore { 154 int e_af; 155 int e_socktype; 156 int e_protocol; 157 const char *e_protostr; 158 int e_wild; 159 #define WILD_AF(ex) ((ex)->e_wild & 0x01) 160 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 161 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 162 }; 163 164 static const struct explore explore[] = { 165 #if 0 166 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 167 #endif 168 #ifdef INET6 169 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 170 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 171 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 172 #endif 173 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 174 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 175 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 176 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 177 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 178 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, 179 { -1, 0, 0, NULL, 0 }, 180 }; 181 182 #ifdef INET6 183 #define PTON_MAX 16 184 #else 185 #define PTON_MAX 4 186 #endif 187 188 #define AIO_SRCFLAG_DEPRECATED 0x1 189 190 struct ai_order { 191 union { 192 struct sockaddr_storage aiou_ss; 193 struct sockaddr aiou_sa; 194 } aio_src_un; 195 #define aio_srcsa aio_src_un.aiou_sa 196 u_int32_t aio_srcflag; 197 int aio_srcscope; 198 int aio_dstscope; 199 struct policyqueue *aio_srcpolicy; 200 struct policyqueue *aio_dstpolicy; 201 struct addrinfo *aio_ai; 202 int aio_matchlen; 203 }; 204 205 static const ns_src default_dns_files[] = { 206 { NSSRC_FILES, NS_SUCCESS }, 207 { NSSRC_DNS, NS_SUCCESS }, 208 { 0 } 209 }; 210 211 struct res_target { 212 struct res_target *next; 213 const char *name; /* domain name */ 214 int qclass, qtype; /* class and type of query */ 215 u_char *answer; /* buffer to put answer */ 216 int anslen; /* size of answer buffer */ 217 int n; /* result length */ 218 }; 219 220 #define MAXPACKET (64*1024) 221 222 typedef union { 223 HEADER hdr; 224 u_char buf[MAXPACKET]; 225 } querybuf; 226 227 static int str2number(const char *, int *); 228 static int explore_null(const struct addrinfo *, 229 const char *, struct addrinfo **); 230 static int explore_numeric(const struct addrinfo *, const char *, 231 const char *, struct addrinfo **, const char *); 232 static int explore_numeric_scope(const struct addrinfo *, const char *, 233 const char *, struct addrinfo **); 234 static int get_canonname(const struct addrinfo *, 235 struct addrinfo *, const char *); 236 static struct addrinfo *get_ai(const struct addrinfo *, 237 const struct afd *, const char *); 238 static int get_portmatch(const struct addrinfo *, const char *); 239 static int get_port(struct addrinfo *, const char *, int); 240 static const struct afd *find_afd(int); 241 static int addrconfig(struct addrinfo *); 242 static void set_source(struct ai_order *, struct policyhead *); 243 static int comp_dst(const void *, const void *); 244 #ifdef INET6 245 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 246 #endif 247 static int gai_addr2scopetype(struct sockaddr *); 248 249 static int explore_fqdn(const struct addrinfo *, const char *, 250 const char *, struct addrinfo **); 251 252 static int reorder(struct addrinfo *); 253 static int get_addrselectpolicy(struct policyhead *); 254 static void free_addrselectpolicy(struct policyhead *); 255 static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 256 struct policyhead *); 257 static int matchlen(struct sockaddr *, struct sockaddr *); 258 259 static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 260 const struct addrinfo *, res_state); 261 #if defined(RESOLVSORT) 262 static int addr4sort(struct addrinfo *, res_state); 263 #endif 264 static int _dns_getaddrinfo(void *, void *, va_list); 265 static void _sethtent(FILE **); 266 static void _endhtent(FILE **); 267 static struct addrinfo *_gethtent(FILE **, const char *, 268 const struct addrinfo *); 269 static int _files_getaddrinfo(void *, void *, va_list); 270 #ifdef YP 271 static struct addrinfo *_yphostent(char *, const struct addrinfo *); 272 static int _yp_getaddrinfo(void *, void *, va_list); 273 #endif 274 #ifdef NS_CACHING 275 static int addrinfo_id_func(char *, size_t *, va_list, void *); 276 static int addrinfo_marshal_func(char *, size_t *, void *, va_list, 277 void *); 278 static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, 279 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, &cur->ai_next); 535 536 while (cur && cur->ai_next) 537 cur = cur->ai_next; 538 } 539 540 /* XXX inhibit errors if we have the result */ 541 if (sentinel.ai_next) 542 error = 0; 543 544 good: 545 /* 546 * ensure we return either: 547 * - error == 0, non-NULL *res 548 * - error != 0, NULL *res 549 */ 550 if (error == 0) { 551 if (sentinel.ai_next) { 552 /* 553 * If the returned entry is for an active connection, 554 * and the given name is not numeric, reorder the 555 * list, so that the application would try the list 556 * in the most efficient order. Since the head entry 557 * of the original list may contain ai_canonname and 558 * that entry may be moved elsewhere in the new list, 559 * we keep the pointer and will restore it in the new 560 * head entry. (Note that RFC3493 requires the head 561 * entry store it when requested by the caller). 562 */ 563 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 564 if (!numeric) { 565 char *canonname; 566 567 canonname = 568 sentinel.ai_next->ai_canonname; 569 sentinel.ai_next->ai_canonname = NULL; 570 reorder(&sentinel); 571 if (sentinel.ai_next->ai_canonname == 572 NULL) { 573 sentinel.ai_next->ai_canonname 574 = canonname; 575 } else if (canonname != NULL) 576 free(canonname); 577 } 578 } 579 *res = sentinel.ai_next; 580 return SUCCESS; 581 } else 582 error = EAI_FAIL; 583 } 584 free: 585 bad: 586 if (sentinel.ai_next) 587 freeaddrinfo(sentinel.ai_next); 588 *res = NULL; 589 return error; 590 } 591 592 static int 593 reorder(struct addrinfo *sentinel) 594 { 595 struct addrinfo *ai, **aip; 596 struct ai_order *aio; 597 int i, n; 598 struct policyhead policyhead; 599 600 /* count the number of addrinfo elements for sorting. */ 601 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 602 ; 603 604 /* 605 * If the number is small enough, we can skip the reordering process. 606 */ 607 if (n <= 1) 608 return(n); 609 610 /* allocate a temporary array for sort and initialization of it. */ 611 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 612 return(n); /* give up reordering */ 613 memset(aio, 0, sizeof(*aio) * n); 614 615 /* retrieve address selection policy from the kernel */ 616 TAILQ_INIT(&policyhead); 617 if (!get_addrselectpolicy(&policyhead)) { 618 /* no policy is installed into kernel, we don't sort. */ 619 free(aio); 620 return (n); 621 } 622 623 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 624 aio[i].aio_ai = ai; 625 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 626 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 627 &policyhead); 628 set_source(&aio[i], &policyhead); 629 } 630 631 /* perform sorting. */ 632 qsort(aio, n, sizeof(*aio), comp_dst); 633 634 /* reorder the addrinfo chain. */ 635 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 636 *aip = aio[i].aio_ai; 637 aip = &aio[i].aio_ai->ai_next; 638 } 639 *aip = NULL; 640 641 /* cleanup and return */ 642 free(aio); 643 free_addrselectpolicy(&policyhead); 644 return(n); 645 } 646 647 static int 648 get_addrselectpolicy(struct policyhead *head) 649 { 650 #ifdef INET6 651 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 652 size_t l; 653 char *buf; 654 struct in6_addrpolicy *pol, *ep; 655 656 if (sysctl(mib, NELEM(mib), NULL, &l, NULL, 0) < 0) 657 return (0); 658 if ((buf = malloc(l)) == NULL) 659 return (0); 660 if (sysctl(mib, NELEM(mib), buf, &l, NULL, 0) < 0) { 661 free(buf); 662 return (0); 663 } 664 665 ep = (struct in6_addrpolicy *)(buf + l); 666 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 667 struct policyqueue *new; 668 669 if ((new = malloc(sizeof(*new))) == NULL) { 670 free_addrselectpolicy(head); /* make the list empty */ 671 break; 672 } 673 new->pc_policy = *pol; 674 TAILQ_INSERT_TAIL(head, new, pc_entry); 675 } 676 677 free(buf); 678 return (1); 679 #else 680 return (0); 681 #endif 682 } 683 684 static void 685 free_addrselectpolicy(struct policyhead *head) 686 { 687 struct policyqueue *ent, *nent; 688 689 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 690 nent = TAILQ_NEXT(ent, pc_entry); 691 TAILQ_REMOVE(head, ent, pc_entry); 692 free(ent); 693 } 694 } 695 696 static struct policyqueue * 697 match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 698 { 699 #ifdef INET6 700 struct policyqueue *ent, *bestent = NULL; 701 struct in6_addrpolicy *pol; 702 int matchlen, bestmatchlen = -1; 703 u_char *mp, *ep, *k, *p, m; 704 struct sockaddr_in6 key; 705 706 switch(addr->sa_family) { 707 case AF_INET6: 708 key = *(struct sockaddr_in6 *)addr; 709 break; 710 case AF_INET: 711 /* convert the address into IPv4-mapped IPv6 address. */ 712 memset(&key, 0, sizeof(key)); 713 key.sin6_family = AF_INET6; 714 key.sin6_len = sizeof(key); 715 key.sin6_addr.s6_addr[10] = 0xff; 716 key.sin6_addr.s6_addr[11] = 0xff; 717 memcpy(&key.sin6_addr.s6_addr[12], 718 &((struct sockaddr_in *)addr)->sin_addr, 4); 719 break; 720 default: 721 return(NULL); 722 } 723 724 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 725 pol = &ent->pc_policy; 726 matchlen = 0; 727 728 mp = (u_char *)&pol->addrmask.sin6_addr; 729 ep = mp + 16; /* XXX: scope field? */ 730 k = (u_char *)&key.sin6_addr; 731 p = (u_char *)&pol->addr.sin6_addr; 732 for (; mp < ep && *mp; mp++, k++, p++) { 733 m = *mp; 734 if ((*k & m) != *p) 735 goto next; /* not match */ 736 if (m == 0xff) /* short cut for a typical case */ 737 matchlen += 8; 738 else { 739 while (m >= 0x80) { 740 matchlen++; 741 m <<= 1; 742 } 743 } 744 } 745 746 /* matched. check if this is better than the current best. */ 747 if (matchlen > bestmatchlen) { 748 bestent = ent; 749 bestmatchlen = matchlen; 750 } 751 752 next: 753 continue; 754 } 755 756 return(bestent); 757 #else 758 return(NULL); 759 #endif 760 761 } 762 763 static void 764 set_source(struct ai_order *aio, struct policyhead *ph) 765 { 766 struct addrinfo ai = *aio->aio_ai; 767 struct sockaddr_storage ss; 768 socklen_t srclen; 769 int s; 770 771 /* set unspec ("no source is available"), just in case */ 772 aio->aio_srcsa.sa_family = AF_UNSPEC; 773 aio->aio_srcscope = -1; 774 775 switch(ai.ai_family) { 776 case AF_INET: 777 #ifdef INET6 778 case AF_INET6: 779 #endif 780 break; 781 default: /* ignore unsupported AFs explicitly */ 782 return; 783 } 784 785 /* XXX: make a dummy addrinfo to call connect() */ 786 ai.ai_socktype = SOCK_DGRAM; 787 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 788 ai.ai_next = NULL; 789 memset(&ss, 0, sizeof(ss)); 790 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 791 ai.ai_addr = (struct sockaddr *)&ss; 792 get_port(&ai, "1", 0); 793 794 /* open a socket to get the source address for the given dst */ 795 if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0) 796 return; /* give up */ 797 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 798 goto cleanup; 799 srclen = ai.ai_addrlen; 800 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 801 aio->aio_srcsa.sa_family = AF_UNSPEC; 802 goto cleanup; 803 } 804 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 805 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 806 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 807 #ifdef INET6 808 if (ai.ai_family == AF_INET6) { 809 struct in6_ifreq ifr6; 810 u_int32_t flags6; 811 812 /* XXX: interface name should not be hardcoded */ 813 strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name)); 814 memset(&ifr6, 0, sizeof(ifr6)); 815 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 816 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 817 flags6 = ifr6.ifr_ifru.ifru_flags6; 818 if ((flags6 & IN6_IFF_DEPRECATED)) 819 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 820 } 821 } 822 #endif 823 824 cleanup: 825 _close(s); 826 return; 827 } 828 829 static int 830 matchlen(struct sockaddr *src, struct sockaddr *dst) 831 { 832 int match = 0; 833 u_char *s, *d; 834 u_char *lim, r; 835 int addrlen; 836 837 switch (src->sa_family) { 838 #ifdef INET6 839 case AF_INET6: 840 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 841 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 842 addrlen = sizeof(struct in6_addr); 843 lim = s + addrlen; 844 break; 845 #endif 846 case AF_INET: 847 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; 848 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; 849 addrlen = sizeof(struct in_addr); 850 lim = s + addrlen; 851 break; 852 default: 853 return(0); 854 } 855 856 while (s < lim) 857 if ((r = (*d++ ^ *s++)) != 0) { 858 while (r < addrlen * 8) { 859 match++; 860 r <<= 1; 861 } 862 break; 863 } else 864 match += 8; 865 return(match); 866 } 867 868 static int 869 comp_dst(const void *arg1, const void *arg2) 870 { 871 const struct ai_order *dst1 = arg1, *dst2 = arg2; 872 873 /* 874 * Rule 1: Avoid unusable destinations. 875 * XXX: we currently do not consider if an appropriate route exists. 876 */ 877 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 878 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 879 return(-1); 880 } 881 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 882 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 883 return(1); 884 } 885 886 /* Rule 2: Prefer matching scope. */ 887 if (dst1->aio_dstscope == dst1->aio_srcscope && 888 dst2->aio_dstscope != dst2->aio_srcscope) { 889 return(-1); 890 } 891 if (dst1->aio_dstscope != dst1->aio_srcscope && 892 dst2->aio_dstscope == dst2->aio_srcscope) { 893 return(1); 894 } 895 896 /* Rule 3: Avoid deprecated addresses. */ 897 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 898 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 899 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 900 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 901 return(-1); 902 } 903 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 904 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 905 return(1); 906 } 907 } 908 909 /* Rule 4: Prefer home addresses. */ 910 /* XXX: not implemented yet */ 911 912 /* Rule 5: Prefer matching label. */ 913 #ifdef INET6 914 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 915 dst1->aio_srcpolicy->pc_policy.label == 916 dst1->aio_dstpolicy->pc_policy.label && 917 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 918 dst2->aio_srcpolicy->pc_policy.label != 919 dst2->aio_dstpolicy->pc_policy.label)) { 920 return(-1); 921 } 922 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 923 dst2->aio_srcpolicy->pc_policy.label == 924 dst2->aio_dstpolicy->pc_policy.label && 925 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 926 dst1->aio_srcpolicy->pc_policy.label != 927 dst1->aio_dstpolicy->pc_policy.label)) { 928 return(1); 929 } 930 #endif 931 932 /* Rule 6: Prefer higher precedence. */ 933 #ifdef INET6 934 if (dst1->aio_dstpolicy && 935 (dst2->aio_dstpolicy == NULL || 936 dst1->aio_dstpolicy->pc_policy.preced > 937 dst2->aio_dstpolicy->pc_policy.preced)) { 938 return(-1); 939 } 940 if (dst2->aio_dstpolicy && 941 (dst1->aio_dstpolicy == NULL || 942 dst2->aio_dstpolicy->pc_policy.preced > 943 dst1->aio_dstpolicy->pc_policy.preced)) { 944 return(1); 945 } 946 #endif 947 948 /* Rule 7: Prefer native transport. */ 949 /* XXX: not implemented yet */ 950 951 /* Rule 8: Prefer smaller scope. */ 952 if (dst1->aio_dstscope >= 0 && 953 dst1->aio_dstscope < dst2->aio_dstscope) { 954 return(-1); 955 } 956 if (dst2->aio_dstscope >= 0 && 957 dst2->aio_dstscope < dst1->aio_dstscope) { 958 return(1); 959 } 960 961 /* 962 * Rule 9: Use longest matching prefix. 963 * We compare the match length in a same AF only. 964 */ 965 if (dst1->aio_ai->ai_addr->sa_family == 966 dst2->aio_ai->ai_addr->sa_family) { 967 if (dst1->aio_matchlen > dst2->aio_matchlen) { 968 return(-1); 969 } 970 if (dst1->aio_matchlen < dst2->aio_matchlen) { 971 return(1); 972 } 973 } 974 975 /* Rule 10: Otherwise, leave the order unchanged. */ 976 return(-1); 977 } 978 979 /* 980 * Copy from scope.c. 981 * XXX: we should standardize the functions and link them as standard 982 * library. 983 */ 984 static int 985 gai_addr2scopetype(struct sockaddr *sa) 986 { 987 #ifdef INET6 988 struct sockaddr_in6 *sa6; 989 #endif 990 struct sockaddr_in *sa4; 991 992 switch(sa->sa_family) { 993 #ifdef INET6 994 case AF_INET6: 995 sa6 = (struct sockaddr_in6 *)sa; 996 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 997 /* just use the scope field of the multicast address */ 998 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 999 } 1000 /* 1001 * Unicast addresses: map scope type to corresponding scope 1002 * value defined for multcast addresses. 1003 * XXX: hardcoded scope type values are bad... 1004 */ 1005 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1006 return(1); /* node local scope */ 1007 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1008 return(2); /* link-local scope */ 1009 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1010 return(5); /* site-local scope */ 1011 return(14); /* global scope */ 1012 break; 1013 #endif 1014 case AF_INET: 1015 /* 1016 * IPv4 pseudo scoping according to RFC 3484. 1017 */ 1018 sa4 = (struct sockaddr_in *)sa; 1019 /* IPv4 autoconfiguration addresses have link-local scope. */ 1020 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1021 ((u_char *)&sa4->sin_addr)[1] == 254) 1022 return(2); 1023 /* Private addresses have site-local scope. */ 1024 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1025 (((u_char *)&sa4->sin_addr)[0] == 172 && 1026 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1027 (((u_char *)&sa4->sin_addr)[0] == 192 && 1028 ((u_char *)&sa4->sin_addr)[1] == 168)) 1029 return(14); /* XXX: It should be 5 unless NAT */ 1030 /* Loopback addresses have link-local scope. */ 1031 if (((u_char *)&sa4->sin_addr)[0] == 127) 1032 return(2); 1033 return(14); 1034 break; 1035 default: 1036 errno = EAFNOSUPPORT; /* is this a good error? */ 1037 return(-1); 1038 } 1039 } 1040 1041 /* 1042 * hostname == NULL. 1043 * passive socket -> anyaddr (0.0.0.0 or ::) 1044 * non-passive socket -> localhost (127.0.0.1 or ::1) 1045 */ 1046 static int 1047 explore_null(const struct addrinfo *pai, const char *servname, 1048 struct addrinfo **res) 1049 { 1050 int s; 1051 const struct afd *afd; 1052 struct addrinfo *ai; 1053 int error; 1054 1055 *res = NULL; 1056 ai = NULL; 1057 1058 /* 1059 * filter out AFs that are not supported by the kernel 1060 * XXX errno? 1061 */ 1062 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1063 if (s < 0) { 1064 if (errno != EMFILE) 1065 return 0; 1066 } else 1067 _close(s); 1068 1069 /* 1070 * if the servname does not match socktype/protocol, ignore it. 1071 */ 1072 if (get_portmatch(pai, servname) != 0) 1073 return 0; 1074 1075 afd = find_afd(pai->ai_family); 1076 if (afd == NULL) 1077 return 0; 1078 1079 if (pai->ai_flags & AI_PASSIVE) { 1080 GET_AI(ai, afd, afd->a_addrany); 1081 GET_PORT(ai, servname); 1082 } else { 1083 GET_AI(ai, afd, afd->a_loopback); 1084 GET_PORT(ai, servname); 1085 } 1086 1087 *res = ai; 1088 return 0; 1089 1090 free: 1091 if (ai != NULL) 1092 freeaddrinfo(ai); 1093 return error; 1094 } 1095 1096 /* 1097 * numeric hostname 1098 */ 1099 static int 1100 explore_numeric(const struct addrinfo *pai, const char *hostname, 1101 const char *servname, struct addrinfo **res, 1102 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 __unused) 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 __unused, void *cache_mdata __unused) 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 __unused, void *retval, 1629 va_list ap __unused, void *cache_mdata __unused) 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 syslog(LOG_NOTICE|LOG_AUTH, 1868 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1869 qname, p_class(C_IN), p_type(qtype), 1870 p_type(type)); 1871 #endif 1872 cp += n; 1873 continue; /* XXX - had_error++ ? */ 1874 } 1875 switch (type) { 1876 case T_A: 1877 case T_AAAA: 1878 if (strcasecmp(canonname, bp) != 0) { 1879 #ifdef DEBUG 1880 syslog(LOG_NOTICE|LOG_AUTH, 1881 AskedForGot, canonname, bp); 1882 #endif 1883 cp += n; 1884 continue; /* XXX - had_error++ ? */ 1885 } 1886 if (type == T_A && n != INADDRSZ) { 1887 cp += n; 1888 continue; 1889 } 1890 if (type == T_AAAA && n != IN6ADDRSZ) { 1891 cp += n; 1892 continue; 1893 } 1894 #ifdef FILTER_V4MAPPED 1895 if (type == T_AAAA) { 1896 struct in6_addr in6; 1897 memcpy(&in6, cp, sizeof(in6)); 1898 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1899 cp += n; 1900 continue; 1901 } 1902 } 1903 #endif 1904 if (!haveanswer) { 1905 int nn; 1906 1907 canonname = bp; 1908 nn = strlen(bp) + 1; /* for the \0 */ 1909 bp += nn; 1910 } 1911 1912 /* don't overwrite pai */ 1913 ai = *pai; 1914 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1915 afd = find_afd(ai.ai_family); 1916 if (afd == NULL) { 1917 cp += n; 1918 continue; 1919 } 1920 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1921 if (cur->ai_next == NULL) 1922 had_error++; 1923 while (cur && cur->ai_next) 1924 cur = cur->ai_next; 1925 cp += n; 1926 break; 1927 default: 1928 abort(); 1929 } 1930 if (!had_error) 1931 haveanswer++; 1932 } 1933 if (haveanswer) { 1934 #if defined(RESOLVSORT) 1935 /* 1936 * We support only IPv4 address for backward 1937 * compatibility against gethostbyname(3). 1938 */ 1939 if (res->nsort && qtype == T_A) { 1940 if (addr4sort(&sentinel, res) < 0) { 1941 freeaddrinfo(sentinel.ai_next); 1942 RES_SET_H_ERRNO(res, NO_RECOVERY); 1943 return NULL; 1944 } 1945 } 1946 #endif /*RESOLVSORT*/ 1947 if (!canonname) 1948 get_canonname(pai, sentinel.ai_next, qname); 1949 else 1950 get_canonname(pai, sentinel.ai_next, canonname); 1951 RES_SET_H_ERRNO(res, NETDB_SUCCESS); 1952 return sentinel.ai_next; 1953 } 1954 1955 RES_SET_H_ERRNO(res, NO_RECOVERY); 1956 return NULL; 1957 } 1958 1959 #ifdef RESOLVSORT 1960 struct addr_ptr { 1961 struct addrinfo *ai; 1962 int aval; 1963 }; 1964 1965 static int 1966 addr4sort(struct addrinfo *sentinel, res_state res) 1967 { 1968 struct addrinfo *ai; 1969 struct addr_ptr *addrs, addr; 1970 struct sockaddr_in *sin; 1971 int naddrs, i, j; 1972 int needsort = 0; 1973 1974 if (!sentinel) 1975 return -1; 1976 naddrs = 0; 1977 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1978 naddrs++; 1979 if (naddrs < 2) 1980 return 0; /* We don't need sorting. */ 1981 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1982 return -1; 1983 i = 0; 1984 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1985 sin = (struct sockaddr_in *)ai->ai_addr; 1986 for (j = 0; (unsigned)j < res->nsort; j++) { 1987 if (res->sort_list[j].addr.s_addr == 1988 (sin->sin_addr.s_addr & res->sort_list[j].mask)) 1989 break; 1990 } 1991 addrs[i].ai = ai; 1992 addrs[i].aval = j; 1993 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1994 needsort = i; 1995 i++; 1996 } 1997 if (!needsort) { 1998 free(addrs); 1999 return 0; 2000 } 2001 2002 while (needsort < naddrs) { 2003 for (j = needsort - 1; j >= 0; j--) { 2004 if (addrs[j].aval > addrs[j+1].aval) { 2005 addr = addrs[j]; 2006 addrs[j] = addrs[j + 1]; 2007 addrs[j + 1] = addr; 2008 } else 2009 break; 2010 } 2011 needsort++; 2012 } 2013 2014 ai = sentinel; 2015 for (i = 0; i < naddrs; ++i) { 2016 ai->ai_next = addrs[i].ai; 2017 ai = ai->ai_next; 2018 } 2019 ai->ai_next = NULL; 2020 free(addrs); 2021 return 0; 2022 } 2023 #endif /*RESOLVSORT*/ 2024 2025 /*ARGSUSED*/ 2026 static int 2027 _dns_getaddrinfo(void *rv, void *cb_data __unused, va_list ap) 2028 { 2029 struct addrinfo *ai; 2030 querybuf *buf, *buf2; 2031 const char *hostname; 2032 const struct addrinfo *pai; 2033 struct addrinfo sentinel, *cur; 2034 struct res_target q, q2; 2035 res_state res; 2036 2037 hostname = va_arg(ap, char *); 2038 pai = va_arg(ap, const struct addrinfo *); 2039 2040 memset(&q, 0, sizeof(q)); 2041 memset(&q2, 0, sizeof(q2)); 2042 memset(&sentinel, 0, sizeof(sentinel)); 2043 cur = &sentinel; 2044 2045 buf = malloc(sizeof(*buf)); 2046 if (!buf) { 2047 h_errno = NETDB_INTERNAL; 2048 return NS_NOTFOUND; 2049 } 2050 buf2 = malloc(sizeof(*buf2)); 2051 if (!buf2) { 2052 free(buf); 2053 h_errno = NETDB_INTERNAL; 2054 return NS_NOTFOUND; 2055 } 2056 2057 switch (pai->ai_family) { 2058 case AF_UNSPEC: 2059 q.name = hostname; 2060 q.qclass = C_IN; 2061 q.qtype = T_A; 2062 q.answer = buf->buf; 2063 q.anslen = sizeof(buf->buf); 2064 q.next = &q2; 2065 q2.name = hostname; 2066 q2.qclass = C_IN; 2067 q2.qtype = T_AAAA; 2068 q2.answer = buf2->buf; 2069 q2.anslen = sizeof(buf2->buf); 2070 break; 2071 case AF_INET: 2072 q.name = hostname; 2073 q.qclass = C_IN; 2074 q.qtype = T_A; 2075 q.answer = buf->buf; 2076 q.anslen = sizeof(buf->buf); 2077 break; 2078 case AF_INET6: 2079 q.name = hostname; 2080 q.qclass = C_IN; 2081 q.qtype = T_AAAA; 2082 q.answer = buf->buf; 2083 q.anslen = sizeof(buf->buf); 2084 break; 2085 default: 2086 free(buf); 2087 free(buf2); 2088 return NS_UNAVAIL; 2089 } 2090 2091 res = __res_state(); 2092 if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) { 2093 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2094 free(buf); 2095 free(buf2); 2096 return NS_NOTFOUND; 2097 } 2098 2099 if (res_searchN(hostname, &q, res) < 0) { 2100 free(buf); 2101 free(buf2); 2102 return NS_NOTFOUND; 2103 } 2104 /* prefer IPv6 */ 2105 if (q.next) { 2106 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res); 2107 if (ai) { 2108 cur->ai_next = ai; 2109 while (cur && cur->ai_next) 2110 cur = cur->ai_next; 2111 } 2112 } 2113 ai = getanswer(buf, q.n, q.name, q.qtype, pai, res); 2114 if (ai) 2115 cur->ai_next = ai; 2116 free(buf); 2117 free(buf2); 2118 if (sentinel.ai_next == NULL) 2119 switch (res->res_h_errno) { 2120 case HOST_NOT_FOUND: 2121 return NS_NOTFOUND; 2122 case TRY_AGAIN: 2123 return NS_TRYAGAIN; 2124 default: 2125 return NS_UNAVAIL; 2126 } 2127 *((struct addrinfo **)rv) = sentinel.ai_next; 2128 return NS_SUCCESS; 2129 } 2130 2131 static void 2132 _sethtent(FILE **hostf) 2133 { 2134 if (!*hostf) 2135 *hostf = fopen(_PATH_HOSTS, "r"); 2136 else 2137 rewind(*hostf); 2138 } 2139 2140 static void 2141 _endhtent(FILE **hostf) 2142 { 2143 if (*hostf) { 2144 fclose(*hostf); 2145 *hostf = NULL; 2146 } 2147 } 2148 2149 static struct addrinfo * 2150 _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2151 { 2152 char *p; 2153 char *cp, *tname, *cname; 2154 struct addrinfo hints, *res0, *res; 2155 int error; 2156 const char *addr; 2157 char hostbuf[8*1024]; 2158 2159 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "r"))) 2160 return (NULL); 2161 again: 2162 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 2163 return (NULL); 2164 if (*p == '#') 2165 goto again; 2166 cp = strpbrk(p, "#\n"); 2167 if (cp != NULL) 2168 *cp = '\0'; 2169 if (!(cp = strpbrk(p, " \t"))) 2170 goto again; 2171 *cp++ = '\0'; 2172 addr = p; 2173 cname = NULL; 2174 /* if this is not something we're looking for, skip it. */ 2175 while (cp && *cp) { 2176 if (*cp == ' ' || *cp == '\t') { 2177 cp++; 2178 continue; 2179 } 2180 tname = cp; 2181 if (cname == NULL) 2182 cname = cp; 2183 if ((cp = strpbrk(cp, " \t")) != NULL) 2184 *cp++ = '\0'; 2185 if (strcasecmp(name, tname) == 0) 2186 goto found; 2187 } 2188 goto again; 2189 2190 found: 2191 /* we should not glob socktype/protocol here */ 2192 memset(&hints, 0, sizeof(hints)); 2193 hints.ai_family = pai->ai_family; 2194 hints.ai_socktype = SOCK_DGRAM; 2195 hints.ai_protocol = 0; 2196 hints.ai_flags = AI_NUMERICHOST; 2197 error = getaddrinfo(addr, "0", &hints, &res0); 2198 if (error) 2199 goto again; 2200 #ifdef FILTER_V4MAPPED 2201 /* XXX should check all items in the chain */ 2202 if (res0->ai_family == AF_INET6 && 2203 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2204 freeaddrinfo(res0); 2205 goto again; 2206 } 2207 #endif 2208 for (res = res0; res; res = res->ai_next) { 2209 /* cover it up */ 2210 res->ai_flags = pai->ai_flags; 2211 res->ai_socktype = pai->ai_socktype; 2212 res->ai_protocol = pai->ai_protocol; 2213 2214 if (pai->ai_flags & AI_CANONNAME) { 2215 if (get_canonname(pai, res, cname) != 0) { 2216 freeaddrinfo(res0); 2217 goto again; 2218 } 2219 } 2220 } 2221 return res0; 2222 } 2223 2224 /*ARGSUSED*/ 2225 static int 2226 _files_getaddrinfo(void *rv, void *cb_data __unused, va_list ap) 2227 { 2228 const char *name; 2229 const struct addrinfo *pai; 2230 struct addrinfo sentinel, *cur; 2231 struct addrinfo *p; 2232 FILE *hostf = NULL; 2233 2234 name = va_arg(ap, char *); 2235 pai = va_arg(ap, struct addrinfo *); 2236 2237 memset(&sentinel, 0, sizeof(sentinel)); 2238 cur = &sentinel; 2239 2240 _sethtent(&hostf); 2241 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2242 cur->ai_next = p; 2243 while (cur && cur->ai_next) 2244 cur = cur->ai_next; 2245 } 2246 _endhtent(&hostf); 2247 2248 *((struct addrinfo **)rv) = sentinel.ai_next; 2249 if (sentinel.ai_next == NULL) 2250 return NS_NOTFOUND; 2251 return NS_SUCCESS; 2252 } 2253 2254 #ifdef YP 2255 /*ARGSUSED*/ 2256 static struct addrinfo * 2257 _yphostent(char *line, const struct addrinfo *pai) 2258 { 2259 struct addrinfo sentinel, *cur; 2260 struct addrinfo hints, *res, *res0; 2261 int error; 2262 char *p = line; 2263 const char *addr, *canonname; 2264 char *nextline; 2265 char *cp; 2266 2267 addr = canonname = NULL; 2268 2269 memset(&sentinel, 0, sizeof(sentinel)); 2270 cur = &sentinel; 2271 2272 nextline: 2273 /* terminate line */ 2274 cp = strchr(p, '\n'); 2275 if (cp) { 2276 *cp++ = '\0'; 2277 nextline = cp; 2278 } else 2279 nextline = NULL; 2280 2281 cp = strpbrk(p, " \t"); 2282 if (cp == NULL) { 2283 if (canonname == NULL) 2284 return (NULL); 2285 else 2286 goto done; 2287 } 2288 *cp++ = '\0'; 2289 2290 addr = p; 2291 2292 while (cp && *cp) { 2293 if (*cp == ' ' || *cp == '\t') { 2294 cp++; 2295 continue; 2296 } 2297 if (!canonname) 2298 canonname = cp; 2299 if ((cp = strpbrk(cp, " \t")) != NULL) 2300 *cp++ = '\0'; 2301 } 2302 2303 hints = *pai; 2304 hints.ai_flags = AI_NUMERICHOST; 2305 error = getaddrinfo(addr, NULL, &hints, &res0); 2306 if (error == 0) { 2307 for (res = res0; res; res = res->ai_next) { 2308 /* cover it up */ 2309 res->ai_flags = pai->ai_flags; 2310 2311 if (pai->ai_flags & AI_CANONNAME) 2312 get_canonname(pai, res, canonname); 2313 } 2314 } else 2315 res0 = NULL; 2316 if (res0) { 2317 cur->ai_next = res0; 2318 while (cur && cur->ai_next) 2319 cur = cur->ai_next; 2320 } 2321 2322 if (nextline) { 2323 p = nextline; 2324 goto nextline; 2325 } 2326 2327 done: 2328 return sentinel.ai_next; 2329 } 2330 2331 /*ARGSUSED*/ 2332 static int 2333 _yp_getaddrinfo(void *rv, void *cb_data __unused, va_list ap) 2334 { 2335 struct addrinfo sentinel, *cur; 2336 struct addrinfo *ai = NULL; 2337 char *ypbuf; 2338 int ypbuflen, r; 2339 const char *name; 2340 const struct addrinfo *pai; 2341 char *ypdomain; 2342 2343 if (_yp_check(&ypdomain) == 0) 2344 return NS_UNAVAIL; 2345 2346 name = va_arg(ap, char *); 2347 pai = va_arg(ap, const struct addrinfo *); 2348 2349 memset(&sentinel, 0, sizeof(sentinel)); 2350 cur = &sentinel; 2351 2352 /* hosts.byname is only for IPv4 (Solaris8) */ 2353 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2354 r = yp_match(ypdomain, "hosts.byname", name, 2355 (int)strlen(name), &ypbuf, &ypbuflen); 2356 if (r == 0) { 2357 struct addrinfo ai4; 2358 2359 ai4 = *pai; 2360 ai4.ai_family = AF_INET; 2361 ai = _yphostent(ypbuf, &ai4); 2362 if (ai) { 2363 cur->ai_next = ai; 2364 while (cur && cur->ai_next) 2365 cur = cur->ai_next; 2366 } 2367 free(ypbuf); 2368 } 2369 } 2370 2371 /* ipnodes.byname can hold both IPv4/v6 */ 2372 r = yp_match(ypdomain, "ipnodes.byname", name, 2373 (int)strlen(name), &ypbuf, &ypbuflen); 2374 if (r == 0) { 2375 ai = _yphostent(ypbuf, pai); 2376 if (ai) 2377 cur->ai_next = ai; 2378 free(ypbuf); 2379 } 2380 2381 if (sentinel.ai_next == NULL) { 2382 RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND); 2383 return NS_NOTFOUND; 2384 } 2385 *((struct addrinfo **)rv) = sentinel.ai_next; 2386 return NS_SUCCESS; 2387 } 2388 #endif 2389 2390 /* resolver logic */ 2391 2392 /* 2393 * Formulate a normal query, send, and await answer. 2394 * Returned answer is placed in supplied buffer "answer". 2395 * Perform preliminary check of answer, returning success only 2396 * if no error is indicated and the answer count is nonzero. 2397 * Return the size of the response on success, -1 on error. 2398 * Error number is left in h_errno. 2399 * 2400 * Caller must parse answer and determine whether it answers the question. 2401 */ 2402 static int 2403 res_queryN(const char *name, struct res_target *target, res_state res) 2404 { 2405 u_char *buf; 2406 HEADER *hp; 2407 int n; 2408 u_int oflags; 2409 struct res_target *t; 2410 int rcode; 2411 int ancount; 2412 2413 rcode = NOERROR; 2414 ancount = 0; 2415 2416 buf = malloc(MAXPACKET); 2417 if (!buf) { 2418 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2419 return -1; 2420 } 2421 2422 for (t = target; t; t = t->next) { 2423 int class, type; 2424 u_char *answer; 2425 int anslen; 2426 2427 hp = (HEADER *)(void *)t->answer; 2428 2429 /* make it easier... */ 2430 class = t->qclass; 2431 type = t->qtype; 2432 answer = t->answer; 2433 anslen = t->anslen; 2434 2435 oflags = res->_flags; 2436 2437 again: 2438 hp->rcode = NOERROR; /* default */ 2439 2440 #ifdef DEBUG 2441 if (res->options & RES_DEBUG) 2442 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2443 #endif 2444 2445 n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL, 2446 buf, MAXPACKET); 2447 if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 && 2448 (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U) 2449 n = res_nopt(res, n, buf, MAXPACKET, anslen); 2450 if (n <= 0) { 2451 #ifdef DEBUG 2452 if (res->options & RES_DEBUG) 2453 printf(";; res_query: mkquery failed\n"); 2454 #endif 2455 free(buf); 2456 RES_SET_H_ERRNO(res, NO_RECOVERY); 2457 return (n); 2458 } 2459 n = res_nsend(res, buf, n, answer, anslen); 2460 if (n < 0) { 2461 /* 2462 * if the query choked with EDNS0, retry 2463 * without EDNS0 2464 */ 2465 if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) 2466 != 0U && 2467 ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) { 2468 res->_flags |= RES_F_EDNS0ERR; 2469 if (res->options & RES_DEBUG) 2470 printf(";; res_nquery: retry without EDNS0\n"); 2471 goto again; 2472 } 2473 rcode = hp->rcode; /* record most recent error */ 2474 #ifdef DEBUG 2475 if (res->options & RES_DEBUG) 2476 printf(";; res_query: send error\n"); 2477 #endif 2478 continue; 2479 } 2480 2481 if (n > anslen) 2482 hp->rcode = FORMERR; /* XXX not very informative */ 2483 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2484 rcode = hp->rcode; /* record most recent error */ 2485 #ifdef DEBUG 2486 if (res->options & RES_DEBUG) 2487 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2488 ntohs(hp->ancount)); 2489 #endif 2490 continue; 2491 } 2492 2493 ancount += ntohs(hp->ancount); 2494 2495 t->n = n; 2496 } 2497 2498 free(buf); 2499 2500 if (ancount == 0) { 2501 switch (rcode) { 2502 case NXDOMAIN: 2503 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); 2504 break; 2505 case SERVFAIL: 2506 RES_SET_H_ERRNO(res, TRY_AGAIN); 2507 break; 2508 case NOERROR: 2509 RES_SET_H_ERRNO(res, NO_DATA); 2510 break; 2511 case FORMERR: 2512 case NOTIMP: 2513 case REFUSED: 2514 default: 2515 RES_SET_H_ERRNO(res, NO_RECOVERY); 2516 break; 2517 } 2518 return (-1); 2519 } 2520 return (ancount); 2521 } 2522 2523 /* 2524 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2525 * Return the size of the response on success, -1 on error. 2526 * If enabled, implement search rules until answer or unrecoverable failure 2527 * is detected. Error code, if any, is left in h_errno. 2528 */ 2529 static int 2530 res_searchN(const char *name, struct res_target *target, res_state res) 2531 { 2532 const char *cp, * const *domain; 2533 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2534 u_int dots; 2535 int trailing_dot, ret, saved_herrno; 2536 int got_nodata = 0, got_servfail = 0, root_on_list = 0; 2537 int tried_as_is = 0; 2538 int searched = 0; 2539 char abuf[MAXDNAME]; 2540 2541 errno = 0; 2542 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */ 2543 dots = 0; 2544 for (cp = name; *cp; cp++) 2545 dots += (*cp == '.'); 2546 trailing_dot = 0; 2547 if (cp > name && *--cp == '.') 2548 trailing_dot++; 2549 2550 /* 2551 * if there aren't any dots, it could be a user-level alias 2552 */ 2553 if (!dots && 2554 (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL) 2555 return (res_queryN(cp, target, res)); 2556 2557 /* 2558 * If there are enough dots in the name, let's just give it a 2559 * try 'as is'. The threshold can be set with the "ndots" option. 2560 * Also, query 'as is', if there is a trailing dot in the name. 2561 */ 2562 saved_herrno = -1; 2563 if (dots >= res->ndots || trailing_dot) { 2564 ret = res_querydomainN(name, NULL, target, res); 2565 if (ret > 0 || trailing_dot) 2566 return (ret); 2567 if (errno == ECONNREFUSED) { 2568 RES_SET_H_ERRNO(res, TRY_AGAIN); 2569 return (-1); 2570 } 2571 switch (res->res_h_errno) { 2572 case NO_DATA: 2573 case HOST_NOT_FOUND: 2574 break; 2575 case TRY_AGAIN: 2576 if (hp->rcode == SERVFAIL) 2577 break; 2578 /* FALLTHROUGH */ 2579 default: 2580 return (-1); 2581 } 2582 saved_herrno = res->res_h_errno; 2583 tried_as_is++; 2584 } 2585 2586 /* 2587 * We do at least one level of search if 2588 * - there is no dot and RES_DEFNAME is set, or 2589 * - there is at least one dot, there is no trailing dot, 2590 * and RES_DNSRCH is set. 2591 */ 2592 if ((!dots && (res->options & RES_DEFNAMES)) || 2593 (dots && !trailing_dot && (res->options & RES_DNSRCH))) { 2594 int done = 0; 2595 2596 for (domain = (const char * const *)res->dnsrch; 2597 *domain && !done; 2598 domain++) { 2599 searched = 1; 2600 2601 if (domain[0][0] == '\0' || 2602 (domain[0][0] == '.' && domain[0][1] == '\0')) 2603 root_on_list++; 2604 2605 if (root_on_list && tried_as_is) 2606 continue; 2607 2608 ret = res_querydomainN(name, *domain, target, res); 2609 if (ret > 0) 2610 return (ret); 2611 2612 /* 2613 * If no server present, give up. 2614 * If name isn't found in this domain, 2615 * keep trying higher domains in the search list 2616 * (if that's enabled). 2617 * On a NO_DATA error, keep trying, otherwise 2618 * a wildcard entry of another type could keep us 2619 * from finding this entry higher in the domain. 2620 * If we get some other error (negative answer or 2621 * server failure), then stop searching up, 2622 * but try the input name below in case it's 2623 * fully-qualified. 2624 */ 2625 if (errno == ECONNREFUSED) { 2626 RES_SET_H_ERRNO(res, TRY_AGAIN); 2627 return (-1); 2628 } 2629 2630 switch (res->res_h_errno) { 2631 case NO_DATA: 2632 got_nodata++; 2633 /* FALLTHROUGH */ 2634 case HOST_NOT_FOUND: 2635 /* keep trying */ 2636 break; 2637 case TRY_AGAIN: 2638 got_servfail++; 2639 if (hp->rcode == SERVFAIL) { 2640 /* try next search element, if any */ 2641 break; 2642 } 2643 /* FALLTHROUGH */ 2644 default: 2645 /* anything else implies that we're done */ 2646 done++; 2647 } 2648 /* 2649 * if we got here for some reason other than DNSRCH, 2650 * we only wanted one iteration of the loop, so stop. 2651 */ 2652 if (!(res->options & RES_DNSRCH)) 2653 done++; 2654 } 2655 } 2656 2657 switch (res->res_h_errno) { 2658 case NO_DATA: 2659 case HOST_NOT_FOUND: 2660 break; 2661 case TRY_AGAIN: 2662 if (hp->rcode == SERVFAIL) 2663 break; 2664 /* FALLTHROUGH */ 2665 default: 2666 goto giveup; 2667 } 2668 2669 /* 2670 * If the query has not already been tried as is then try it 2671 * unless RES_NOTLDQUERY is set and there were no dots. 2672 */ 2673 if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) && 2674 !(tried_as_is || root_on_list)) { 2675 ret = res_querydomainN(name, NULL, target, res); 2676 if (ret > 0) 2677 return (ret); 2678 } 2679 2680 /* 2681 * if we got here, we didn't satisfy the search. 2682 * if we did an initial full query, return that query's h_errno 2683 * (note that we wouldn't be here if that query had succeeded). 2684 * else if we ever got a nodata, send that back as the reason. 2685 * else send back meaningless h_errno, that being the one from 2686 * the last DNSRCH we did. 2687 */ 2688 giveup: 2689 if (saved_herrno != -1) 2690 RES_SET_H_ERRNO(res, saved_herrno); 2691 else if (got_nodata) 2692 RES_SET_H_ERRNO(res, NO_DATA); 2693 else if (got_servfail) 2694 RES_SET_H_ERRNO(res, TRY_AGAIN); 2695 return (-1); 2696 } 2697 2698 /* 2699 * Perform a call on res_query on the concatenation of name and domain, 2700 * removing a trailing dot from name if domain is NULL. 2701 */ 2702 static int 2703 res_querydomainN(const char *name, const char *domain, 2704 struct res_target *target, res_state res) 2705 { 2706 char nbuf[MAXDNAME]; 2707 const char *longname = nbuf; 2708 size_t n, d; 2709 2710 #ifdef DEBUG 2711 if (res->options & RES_DEBUG) 2712 printf(";; res_querydomain(%s, %s)\n", 2713 name, domain?domain:"<Nil>"); 2714 #endif 2715 if (domain == NULL) { 2716 /* 2717 * Check for trailing '.'; 2718 * copy without '.' if present. 2719 */ 2720 n = strlen(name); 2721 if (n >= MAXDNAME) { 2722 RES_SET_H_ERRNO(res, NO_RECOVERY); 2723 return (-1); 2724 } 2725 if (n > 0 && name[--n] == '.') { 2726 strncpy(nbuf, name, n); 2727 nbuf[n] = '\0'; 2728 } else 2729 longname = name; 2730 } else { 2731 n = strlen(name); 2732 d = strlen(domain); 2733 if (n + d + 1 >= MAXDNAME) { 2734 RES_SET_H_ERRNO(res, NO_RECOVERY); 2735 return (-1); 2736 } 2737 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2738 } 2739 return (res_queryN(longname, target, res)); 2740 } 2741