1 /* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * "#ifdef FAITH" part is local hack for supporting IPv4-v6 translator. 34 * 35 * Issues to be discussed: 36 * - Thread safe-ness must be checked. 37 * - Return values. There are nonstandard return values defined and used 38 * in the source code. This is because RFC2553 is silent about which error 39 * code must be returned for which situation. 40 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 41 * invalid. current code - SEGV on freeaddrinfo(NULL) 42 * 43 * Note: 44 * - The code filters out AFs that are not supported by the kernel, 45 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 46 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 47 * in ai_flags? 48 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 49 * (1) what should we do against numeric hostname (2) what should we do 50 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 51 * non-loopback address configured? global address configured? 52 * 53 * OS specific notes for netbsd/openbsd/freebsd4/bsdi4: 54 * - To avoid search order issue, we have a big amount of code duplicate 55 * from gethnamaddr.c and some other places. The issues that there's no 56 * lower layer function to lookup "IPv4 or IPv6" record. Calling 57 * gethostbyname2 from getaddrinfo will end up in wrong search order, as 58 * presented above. 59 * 60 * OS specific notes for freebsd4: 61 * - FreeBSD supported $GAI. The code does not. 62 * - FreeBSD allowed classful IPv4 numeric (127.1), the code does not. 63 */ 64 65 #include <sys/cdefs.h> 66 __FBSDID("$FreeBSD$"); 67 68 #include "namespace.h" 69 #include <sys/types.h> 70 #include <sys/param.h> 71 #include <sys/socket.h> 72 #include <net/if.h> 73 #include <netinet/in.h> 74 #include <sys/queue.h> 75 #ifdef INET6 76 #include <net/if_var.h> 77 #include <sys/sysctl.h> 78 #include <sys/ioctl.h> 79 #include <netinet6/in6_var.h> /* XXX */ 80 #endif 81 #include <arpa/inet.h> 82 #include <arpa/nameser.h> 83 #include <rpc/rpc.h> 84 #include <rpcsvc/yp_prot.h> 85 #include <rpcsvc/ypclnt.h> 86 #include <netdb.h> 87 #include <resolv.h> 88 #include <string.h> 89 #include <stdlib.h> 90 #include <stddef.h> 91 #include <ctype.h> 92 #include <unistd.h> 93 #include <stdio.h> 94 #include <errno.h> 95 96 #include "res_config.h" 97 98 #ifdef DEBUG 99 #include <syslog.h> 100 #endif 101 102 #include <stdarg.h> 103 #include <nsswitch.h> 104 #include "un-namespace.h" 105 #include "libc_private.h" 106 107 #if defined(__KAME__) && defined(INET6) 108 # define FAITH 109 #endif 110 111 #define SUCCESS 0 112 #define ANY 0 113 #define YES 1 114 #define NO 0 115 116 static const char in_addrany[] = { 0, 0, 0, 0 }; 117 static const char in_loopback[] = { 127, 0, 0, 1 }; 118 #ifdef INET6 119 static const char in6_addrany[] = { 120 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 121 }; 122 static const char in6_loopback[] = { 123 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 124 }; 125 #endif 126 127 struct policyqueue { 128 TAILQ_ENTRY(policyqueue) pc_entry; 129 #ifdef INET6 130 struct in6_addrpolicy pc_policy; 131 #endif 132 }; 133 TAILQ_HEAD(policyhead, policyqueue); 134 135 static const struct afd { 136 int a_af; 137 int a_addrlen; 138 socklen_t a_socklen; 139 int a_off; 140 const char *a_addrany; 141 const char *a_loopback; 142 int a_scoped; 143 } afdl [] = { 144 #ifdef INET6 145 #define N_INET6 0 146 {PF_INET6, sizeof(struct in6_addr), 147 sizeof(struct sockaddr_in6), 148 offsetof(struct sockaddr_in6, sin6_addr), 149 in6_addrany, in6_loopback, 1}, 150 #define N_INET 1 151 #else 152 #define N_INET 0 153 #endif 154 {PF_INET, sizeof(struct in_addr), 155 sizeof(struct sockaddr_in), 156 offsetof(struct sockaddr_in, sin_addr), 157 in_addrany, in_loopback, 0}, 158 {0, 0, 0, 0, NULL, NULL, 0}, 159 }; 160 161 struct explore { 162 int e_af; 163 int e_socktype; 164 int e_protocol; 165 const char *e_protostr; 166 int e_wild; 167 #define WILD_AF(ex) ((ex)->e_wild & 0x01) 168 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 169 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 170 }; 171 172 static const struct explore explore[] = { 173 #if 0 174 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 175 #endif 176 #ifdef INET6 177 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 178 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 179 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 180 #endif 181 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 182 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 183 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 184 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 185 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 186 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, 187 { -1, 0, 0, NULL, 0 }, 188 }; 189 190 #ifdef INET6 191 #define PTON_MAX 16 192 #else 193 #define PTON_MAX 4 194 #endif 195 196 #define AIO_SRCFLAG_DEPRECATED 0x1 197 198 struct ai_order { 199 union { 200 struct sockaddr_storage aiou_ss; 201 struct sockaddr aiou_sa; 202 } aio_src_un; 203 #define aio_srcsa aio_src_un.aiou_sa 204 u_int32_t aio_srcflag; 205 int aio_srcscope; 206 int aio_dstscope; 207 struct policyqueue *aio_srcpolicy; 208 struct policyqueue *aio_dstpolicy; 209 struct addrinfo *aio_ai; 210 int aio_matchlen; 211 }; 212 213 static const ns_src default_dns_files[] = { 214 { NSSRC_FILES, NS_SUCCESS }, 215 { NSSRC_DNS, NS_SUCCESS }, 216 { 0 } 217 }; 218 219 struct res_target { 220 struct res_target *next; 221 const char *name; /* domain name */ 222 int qclass, qtype; /* class and type of query */ 223 u_char *answer; /* buffer to put answer */ 224 int anslen; /* size of answer buffer */ 225 int n; /* result length */ 226 }; 227 228 #define MAXPACKET (64*1024) 229 230 typedef union { 231 HEADER hdr; 232 u_char buf[MAXPACKET]; 233 } querybuf; 234 235 static int str2number(const char *); 236 static int explore_null(const struct addrinfo *, 237 const char *, struct addrinfo **); 238 static int explore_numeric(const struct addrinfo *, const char *, 239 const char *, struct addrinfo **, const char *); 240 static int explore_numeric_scope(const struct addrinfo *, const char *, 241 const char *, struct addrinfo **); 242 static int get_canonname(const struct addrinfo *, 243 struct addrinfo *, const char *); 244 static struct addrinfo *get_ai(const struct addrinfo *, 245 const struct afd *, const char *); 246 static int get_portmatch(const struct addrinfo *, const char *); 247 static int get_port(struct addrinfo *, const char *, int); 248 static const struct afd *find_afd(int); 249 static int addrconfig(struct addrinfo *); 250 static void set_source(struct ai_order *, struct policyhead *); 251 static int comp_dst(const void *, const void *); 252 #ifdef INET6 253 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 254 #endif 255 static int gai_addr2scopetype(struct sockaddr *); 256 257 static int explore_fqdn(const struct addrinfo *, const char *, 258 const char *, struct addrinfo **); 259 260 static int reorder(struct addrinfo *); 261 static int get_addrselectpolicy(struct policyhead *); 262 static void free_addrselectpolicy(struct policyhead *); 263 static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 264 struct policyhead *); 265 static int matchlen(struct sockaddr *, struct sockaddr *); 266 267 static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 268 const struct addrinfo *, res_state); 269 #if defined(RESOLVSORT) 270 static int addr4sort(struct addrinfo *, res_state); 271 #endif 272 static int _dns_getaddrinfo(void *, void *, va_list); 273 static void _sethtent(FILE **); 274 static void _endhtent(FILE **); 275 static struct addrinfo *_gethtent(FILE **, const char *, 276 const struct addrinfo *); 277 static int _files_getaddrinfo(void *, void *, va_list); 278 #ifdef YP 279 static struct addrinfo *_yphostent(char *, const struct addrinfo *); 280 static int _yp_getaddrinfo(void *, void *, va_list); 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) 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 return v; 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 * post-2553: AI_ALL and AI_V4MAPPED are effective only against 429 * AF_INET6 query. They need to be ignored if specified in other 430 * occassions. 431 */ 432 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 433 case AI_V4MAPPED: 434 case AI_ALL | AI_V4MAPPED: 435 if (pai->ai_family != AF_INET6) 436 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 437 break; 438 case AI_ALL: 439 #if 1 440 /* illegal */ 441 ERR(EAI_BADFLAGS); 442 #else 443 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 444 #endif 445 break; 446 } 447 448 /* 449 * check for special cases. (1) numeric servname is disallowed if 450 * socktype/protocol are left unspecified. (2) servname is disallowed 451 * for raw and other inet{,6} sockets. 452 */ 453 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 454 #ifdef PF_INET6 455 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 456 #endif 457 ) { 458 ai0 = *pai; /* backup *pai */ 459 460 if (pai->ai_family == PF_UNSPEC) { 461 #ifdef PF_INET6 462 pai->ai_family = PF_INET6; 463 #else 464 pai->ai_family = PF_INET; 465 #endif 466 } 467 error = get_portmatch(pai, servname); 468 if (error) 469 ERR(error); 470 471 *pai = ai0; 472 } 473 474 ai0 = *pai; 475 476 /* NULL hostname, or numeric hostname */ 477 for (ex = explore; ex->e_af >= 0; ex++) { 478 *pai = ai0; 479 480 /* PF_UNSPEC entries are prepared for DNS queries only */ 481 if (ex->e_af == PF_UNSPEC) 482 continue; 483 484 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 485 continue; 486 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 487 continue; 488 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 489 continue; 490 491 if (pai->ai_family == PF_UNSPEC) 492 pai->ai_family = ex->e_af; 493 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 494 pai->ai_socktype = ex->e_socktype; 495 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 496 pai->ai_protocol = ex->e_protocol; 497 498 if (hostname == NULL) 499 error = explore_null(pai, servname, &cur->ai_next); 500 else 501 error = explore_numeric_scope(pai, hostname, servname, 502 &cur->ai_next); 503 504 if (error) 505 goto free; 506 507 while (cur && cur->ai_next) 508 cur = cur->ai_next; 509 } 510 511 /* 512 * XXX 513 * If numreic representation of AF1 can be interpreted as FQDN 514 * representation of AF2, we need to think again about the code below. 515 */ 516 if (sentinel.ai_next) { 517 numeric = 1; 518 goto good; 519 } 520 521 if (hostname == NULL) 522 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 523 if (pai->ai_flags & AI_NUMERICHOST) 524 ERR(EAI_NONAME); 525 526 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 527 ERR(EAI_FAIL); 528 529 /* 530 * hostname as alphabetical name. 531 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 532 * outer loop by AFs. 533 */ 534 for (ex = explore; ex->e_af >= 0; ex++) { 535 *pai = ai0; 536 537 /* require exact match for family field */ 538 if (pai->ai_family != ex->e_af) 539 continue; 540 541 if (!MATCH(pai->ai_socktype, ex->e_socktype, 542 WILD_SOCKTYPE(ex))) { 543 continue; 544 } 545 if (!MATCH(pai->ai_protocol, ex->e_protocol, 546 WILD_PROTOCOL(ex))) { 547 continue; 548 } 549 550 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 551 pai->ai_socktype = ex->e_socktype; 552 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 553 pai->ai_protocol = ex->e_protocol; 554 555 error = explore_fqdn(pai, hostname, servname, 556 &cur->ai_next); 557 558 while (cur && cur->ai_next) 559 cur = cur->ai_next; 560 } 561 562 /* XXX inhibit errors if we have the result */ 563 if (sentinel.ai_next) 564 error = 0; 565 566 good: 567 /* 568 * ensure we return either: 569 * - error == 0, non-NULL *res 570 * - error != 0, NULL *res 571 */ 572 if (error == 0) { 573 if (sentinel.ai_next) { 574 /* 575 * If the returned entry is for an active connection, 576 * and the given name is not numeric, reorder the 577 * list, so that the application would try the list 578 * in the most efficient order. 579 */ 580 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 581 if (!numeric) 582 (void)reorder(&sentinel); 583 } 584 *res = sentinel.ai_next; 585 return SUCCESS; 586 } else 587 error = EAI_FAIL; 588 } 589 free: 590 bad: 591 if (sentinel.ai_next) 592 freeaddrinfo(sentinel.ai_next); 593 *res = NULL; 594 return error; 595 } 596 597 static int 598 reorder(struct addrinfo *sentinel) 599 { 600 struct addrinfo *ai, **aip; 601 struct ai_order *aio; 602 int i, n; 603 struct policyhead policyhead; 604 605 /* count the number of addrinfo elements for sorting. */ 606 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 607 ; 608 609 /* 610 * If the number is small enough, we can skip the reordering process. 611 */ 612 if (n <= 1) 613 return(n); 614 615 /* allocate a temporary array for sort and initialization of it. */ 616 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 617 return(n); /* give up reordering */ 618 memset(aio, 0, sizeof(*aio) * n); 619 620 /* retrieve address selection policy from the kernel */ 621 TAILQ_INIT(&policyhead); 622 if (!get_addrselectpolicy(&policyhead)) { 623 /* no policy is installed into kernel, we don't sort. */ 624 free(aio); 625 return (n); 626 } 627 628 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 629 aio[i].aio_ai = ai; 630 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 631 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 632 &policyhead); 633 set_source(&aio[i], &policyhead); 634 } 635 636 /* perform sorting. */ 637 qsort(aio, n, sizeof(*aio), comp_dst); 638 639 /* reorder the addrinfo chain. */ 640 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 641 *aip = aio[i].aio_ai; 642 aip = &aio[i].aio_ai->ai_next; 643 } 644 *aip = NULL; 645 646 /* cleanup and return */ 647 free(aio); 648 free_addrselectpolicy(&policyhead); 649 return(n); 650 } 651 652 static int 653 get_addrselectpolicy(struct policyhead *head) 654 { 655 #ifdef INET6 656 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 657 size_t l; 658 char *buf; 659 struct in6_addrpolicy *pol, *ep; 660 661 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 662 return (0); 663 if ((buf = malloc(l)) == NULL) 664 return (0); 665 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 666 free(buf); 667 return (0); 668 } 669 670 ep = (struct in6_addrpolicy *)(buf + l); 671 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 672 struct policyqueue *new; 673 674 if ((new = malloc(sizeof(*new))) == NULL) { 675 free_addrselectpolicy(head); /* make the list empty */ 676 break; 677 } 678 new->pc_policy = *pol; 679 TAILQ_INSERT_TAIL(head, new, pc_entry); 680 } 681 682 free(buf); 683 return (1); 684 #else 685 return (0); 686 #endif 687 } 688 689 static void 690 free_addrselectpolicy(struct policyhead *head) 691 { 692 struct policyqueue *ent, *nent; 693 694 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 695 nent = TAILQ_NEXT(ent, pc_entry); 696 TAILQ_REMOVE(head, ent, pc_entry); 697 free(ent); 698 } 699 } 700 701 static struct policyqueue * 702 match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 703 { 704 #ifdef INET6 705 struct policyqueue *ent, *bestent = NULL; 706 struct in6_addrpolicy *pol; 707 int matchlen, bestmatchlen = -1; 708 u_char *mp, *ep, *k, *p, m; 709 struct sockaddr_in6 key; 710 711 switch(addr->sa_family) { 712 case AF_INET6: 713 key = *(struct sockaddr_in6 *)addr; 714 break; 715 case AF_INET: 716 /* convert the address into IPv4-mapped IPv6 address. */ 717 memset(&key, 0, sizeof(key)); 718 key.sin6_family = AF_INET6; 719 key.sin6_len = sizeof(key); 720 key.sin6_addr.s6_addr[10] = 0xff; 721 key.sin6_addr.s6_addr[11] = 0xff; 722 memcpy(&key.sin6_addr.s6_addr[12], 723 &((struct sockaddr_in *)addr)->sin_addr, 4); 724 break; 725 default: 726 return(NULL); 727 } 728 729 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 730 pol = &ent->pc_policy; 731 matchlen = 0; 732 733 mp = (u_char *)&pol->addrmask.sin6_addr; 734 ep = mp + 16; /* XXX: scope field? */ 735 k = (u_char *)&key.sin6_addr; 736 p = (u_char *)&pol->addr.sin6_addr; 737 for (; mp < ep && *mp; mp++, k++, p++) { 738 m = *mp; 739 if ((*k & m) != *p) 740 goto next; /* not match */ 741 if (m == 0xff) /* short cut for a typical case */ 742 matchlen += 8; 743 else { 744 while (m >= 0x80) { 745 matchlen++; 746 m <<= 1; 747 } 748 } 749 } 750 751 /* matched. check if this is better than the current best. */ 752 if (matchlen > bestmatchlen) { 753 bestent = ent; 754 bestmatchlen = matchlen; 755 } 756 757 next: 758 continue; 759 } 760 761 return(bestent); 762 #else 763 return(NULL); 764 #endif 765 766 } 767 768 static void 769 set_source(struct ai_order *aio, struct policyhead *ph) 770 { 771 struct addrinfo ai = *aio->aio_ai; 772 struct sockaddr_storage ss; 773 socklen_t srclen; 774 int s; 775 776 /* set unspec ("no source is available"), just in case */ 777 aio->aio_srcsa.sa_family = AF_UNSPEC; 778 aio->aio_srcscope = -1; 779 780 switch(ai.ai_family) { 781 case AF_INET: 782 #ifdef INET6 783 case AF_INET6: 784 #endif 785 break; 786 default: /* ignore unsupported AFs explicitly */ 787 return; 788 } 789 790 /* XXX: make a dummy addrinfo to call connect() */ 791 ai.ai_socktype = SOCK_DGRAM; 792 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 793 ai.ai_next = NULL; 794 memset(&ss, 0, sizeof(ss)); 795 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 796 ai.ai_addr = (struct sockaddr *)&ss; 797 get_port(&ai, "1", 0); 798 799 /* open a socket to get the source address for the given dst */ 800 if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0) 801 return; /* give up */ 802 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 803 goto cleanup; 804 srclen = ai.ai_addrlen; 805 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 806 aio->aio_srcsa.sa_family = AF_UNSPEC; 807 goto cleanup; 808 } 809 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 810 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 811 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 812 #ifdef INET6 813 if (ai.ai_family == AF_INET6) { 814 struct in6_ifreq ifr6; 815 u_int32_t flags6; 816 817 /* XXX: interface name should not be hardcoded */ 818 strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name)); 819 memset(&ifr6, 0, sizeof(ifr6)); 820 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 821 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 822 flags6 = ifr6.ifr_ifru.ifru_flags6; 823 if ((flags6 & IN6_IFF_DEPRECATED)) 824 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 825 } 826 } 827 #endif 828 829 cleanup: 830 _close(s); 831 return; 832 } 833 834 static int 835 matchlen(struct sockaddr *src, struct sockaddr *dst) 836 { 837 int match = 0; 838 u_char *s, *d; 839 u_char *lim, r; 840 int addrlen; 841 842 switch (src->sa_family) { 843 #ifdef INET6 844 case AF_INET6: 845 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 846 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 847 addrlen = sizeof(struct in6_addr); 848 lim = s + addrlen; 849 break; 850 #endif 851 case AF_INET: 852 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; 853 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; 854 addrlen = sizeof(struct in_addr); 855 lim = s + addrlen; 856 break; 857 default: 858 return(0); 859 } 860 861 while (s < lim) 862 if ((r = (*d++ ^ *s++)) != 0) { 863 while (r < addrlen * 8) { 864 match++; 865 r <<= 1; 866 } 867 break; 868 } else 869 match += 8; 870 return(match); 871 } 872 873 static int 874 comp_dst(const void *arg1, const void *arg2) 875 { 876 const struct ai_order *dst1 = arg1, *dst2 = arg2; 877 878 /* 879 * Rule 1: Avoid unusable destinations. 880 * XXX: we currently do not consider if an appropriate route exists. 881 */ 882 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 883 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 884 return(-1); 885 } 886 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 887 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 888 return(1); 889 } 890 891 /* Rule 2: Prefer matching scope. */ 892 if (dst1->aio_dstscope == dst1->aio_srcscope && 893 dst2->aio_dstscope != dst2->aio_srcscope) { 894 return(-1); 895 } 896 if (dst1->aio_dstscope != dst1->aio_srcscope && 897 dst2->aio_dstscope == dst2->aio_srcscope) { 898 return(1); 899 } 900 901 /* Rule 3: Avoid deprecated addresses. */ 902 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 903 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 904 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 905 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 906 return(-1); 907 } 908 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 909 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 910 return(1); 911 } 912 } 913 914 /* Rule 4: Prefer home addresses. */ 915 /* XXX: not implemented yet */ 916 917 /* Rule 5: Prefer matching label. */ 918 #ifdef INET6 919 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 920 dst1->aio_srcpolicy->pc_policy.label == 921 dst1->aio_dstpolicy->pc_policy.label && 922 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 923 dst2->aio_srcpolicy->pc_policy.label != 924 dst2->aio_dstpolicy->pc_policy.label)) { 925 return(-1); 926 } 927 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 928 dst2->aio_srcpolicy->pc_policy.label == 929 dst2->aio_dstpolicy->pc_policy.label && 930 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 931 dst1->aio_srcpolicy->pc_policy.label != 932 dst1->aio_dstpolicy->pc_policy.label)) { 933 return(1); 934 } 935 #endif 936 937 /* Rule 6: Prefer higher precedence. */ 938 #ifdef INET6 939 if (dst1->aio_dstpolicy && 940 (dst2->aio_dstpolicy == NULL || 941 dst1->aio_dstpolicy->pc_policy.preced > 942 dst2->aio_dstpolicy->pc_policy.preced)) { 943 return(-1); 944 } 945 if (dst2->aio_dstpolicy && 946 (dst1->aio_dstpolicy == NULL || 947 dst2->aio_dstpolicy->pc_policy.preced > 948 dst1->aio_dstpolicy->pc_policy.preced)) { 949 return(1); 950 } 951 #endif 952 953 /* Rule 7: Prefer native transport. */ 954 /* XXX: not implemented yet */ 955 956 /* Rule 8: Prefer smaller scope. */ 957 if (dst1->aio_dstscope >= 0 && 958 dst1->aio_dstscope < dst2->aio_dstscope) { 959 return(-1); 960 } 961 if (dst2->aio_dstscope >= 0 && 962 dst2->aio_dstscope < dst1->aio_dstscope) { 963 return(1); 964 } 965 966 /* 967 * Rule 9: Use longest matching prefix. 968 * We compare the match length in a same AF only. 969 */ 970 if (dst1->aio_ai->ai_addr->sa_family == 971 dst2->aio_ai->ai_addr->sa_family) { 972 if (dst1->aio_matchlen > dst2->aio_matchlen) { 973 return(-1); 974 } 975 if (dst1->aio_matchlen < dst2->aio_matchlen) { 976 return(1); 977 } 978 } 979 980 /* Rule 10: Otherwise, leave the order unchanged. */ 981 return(-1); 982 } 983 984 /* 985 * Copy from scope.c. 986 * XXX: we should standardize the functions and link them as standard 987 * library. 988 */ 989 static int 990 gai_addr2scopetype(struct sockaddr *sa) 991 { 992 #ifdef INET6 993 struct sockaddr_in6 *sa6; 994 #endif 995 struct sockaddr_in *sa4; 996 997 switch(sa->sa_family) { 998 #ifdef INET6 999 case AF_INET6: 1000 sa6 = (struct sockaddr_in6 *)sa; 1001 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1002 /* just use the scope field of the multicast address */ 1003 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1004 } 1005 /* 1006 * Unicast addresses: map scope type to corresponding scope 1007 * value defined for multcast addresses. 1008 * XXX: hardcoded scope type values are bad... 1009 */ 1010 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1011 return(1); /* node local scope */ 1012 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1013 return(2); /* link-local scope */ 1014 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1015 return(5); /* site-local scope */ 1016 return(14); /* global scope */ 1017 break; 1018 #endif 1019 case AF_INET: 1020 /* 1021 * IPv4 pseudo scoping according to RFC 3484. 1022 */ 1023 sa4 = (struct sockaddr_in *)sa; 1024 /* IPv4 autoconfiguration addresses have link-local scope. */ 1025 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1026 ((u_char *)&sa4->sin_addr)[1] == 254) 1027 return(2); 1028 /* Private addresses have site-local scope. */ 1029 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1030 (((u_char *)&sa4->sin_addr)[0] == 172 && 1031 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1032 (((u_char *)&sa4->sin_addr)[0] == 192 && 1033 ((u_char *)&sa4->sin_addr)[1] == 168)) 1034 return(14); /* XXX: It should be 5 unless NAT */ 1035 /* Loopback addresses have link-local scope. */ 1036 if (((u_char *)&sa4->sin_addr)[0] == 127) 1037 return(2); 1038 return(14); 1039 break; 1040 default: 1041 errno = EAFNOSUPPORT; /* is this a good error? */ 1042 return(-1); 1043 } 1044 } 1045 1046 /* 1047 * hostname == NULL. 1048 * passive socket -> anyaddr (0.0.0.0 or ::) 1049 * non-passive socket -> localhost (127.0.0.1 or ::1) 1050 */ 1051 static int 1052 explore_null(const struct addrinfo *pai, const char *servname, 1053 struct addrinfo **res) 1054 { 1055 int s; 1056 const struct afd *afd; 1057 struct addrinfo *cur; 1058 struct addrinfo sentinel; 1059 int error; 1060 1061 *res = NULL; 1062 sentinel.ai_next = NULL; 1063 cur = &sentinel; 1064 1065 /* 1066 * filter out AFs that are not supported by the kernel 1067 * XXX errno? 1068 */ 1069 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1070 if (s < 0) { 1071 if (errno != EMFILE) 1072 return 0; 1073 } else 1074 _close(s); 1075 1076 /* 1077 * if the servname does not match socktype/protocol, ignore it. 1078 */ 1079 if (get_portmatch(pai, servname) != 0) 1080 return 0; 1081 1082 afd = find_afd(pai->ai_family); 1083 if (afd == NULL) 1084 return 0; 1085 1086 if (pai->ai_flags & AI_PASSIVE) { 1087 GET_AI(cur->ai_next, afd, afd->a_addrany); 1088 /* xxx meaningless? 1089 * GET_CANONNAME(cur->ai_next, "anyaddr"); 1090 */ 1091 GET_PORT(cur->ai_next, servname); 1092 } else { 1093 GET_AI(cur->ai_next, afd, afd->a_loopback); 1094 /* xxx meaningless? 1095 * GET_CANONNAME(cur->ai_next, "localhost"); 1096 */ 1097 GET_PORT(cur->ai_next, servname); 1098 } 1099 cur = cur->ai_next; 1100 1101 *res = sentinel.ai_next; 1102 return 0; 1103 1104 free: 1105 if (sentinel.ai_next) 1106 freeaddrinfo(sentinel.ai_next); 1107 return error; 1108 } 1109 1110 /* 1111 * numeric hostname 1112 */ 1113 static int 1114 explore_numeric(const struct addrinfo *pai, const char *hostname, 1115 const char *servname, struct addrinfo **res, const char *canonname) 1116 { 1117 const struct afd *afd; 1118 struct addrinfo *cur; 1119 struct addrinfo sentinel; 1120 int error; 1121 char pton[PTON_MAX]; 1122 1123 *res = NULL; 1124 sentinel.ai_next = NULL; 1125 cur = &sentinel; 1126 1127 /* 1128 * if the servname does not match socktype/protocol, ignore it. 1129 */ 1130 if (get_portmatch(pai, servname) != 0) 1131 return 0; 1132 1133 afd = find_afd(pai->ai_family); 1134 if (afd == NULL) 1135 return 0; 1136 1137 switch (afd->a_af) { 1138 #if 1 /*X/Open spec*/ 1139 case AF_INET: 1140 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 1141 if (pai->ai_family == afd->a_af || 1142 pai->ai_family == PF_UNSPEC /*?*/) { 1143 GET_AI(cur->ai_next, afd, pton); 1144 GET_PORT(cur->ai_next, servname); 1145 if ((pai->ai_flags & AI_CANONNAME)) { 1146 /* 1147 * Set the numeric address itself as 1148 * the canonical name, based on a 1149 * clarification in rfc3493. 1150 */ 1151 GET_CANONNAME(cur->ai_next, canonname); 1152 } 1153 while (cur && cur->ai_next) 1154 cur = cur->ai_next; 1155 } else 1156 ERR(EAI_FAMILY); /*xxx*/ 1157 } 1158 break; 1159 #endif 1160 default: 1161 if (inet_pton(afd->a_af, hostname, pton) == 1) { 1162 if (pai->ai_family == afd->a_af || 1163 pai->ai_family == PF_UNSPEC /*?*/) { 1164 GET_AI(cur->ai_next, afd, pton); 1165 GET_PORT(cur->ai_next, servname); 1166 if ((pai->ai_flags & AI_CANONNAME)) { 1167 /* 1168 * Set the numeric address itself as 1169 * the canonical name, based on a 1170 * clarification in rfc3493. 1171 */ 1172 GET_CANONNAME(cur->ai_next, canonname); 1173 } 1174 while (cur && cur->ai_next) 1175 cur = cur->ai_next; 1176 } else 1177 ERR(EAI_FAMILY); /* XXX */ 1178 } 1179 break; 1180 } 1181 1182 *res = sentinel.ai_next; 1183 return 0; 1184 1185 free: 1186 bad: 1187 if (sentinel.ai_next) 1188 freeaddrinfo(sentinel.ai_next); 1189 return error; 1190 } 1191 1192 /* 1193 * numeric hostname with scope 1194 */ 1195 static int 1196 explore_numeric_scope(const struct addrinfo *pai, const char *hostname, 1197 const char *servname, struct addrinfo **res) 1198 { 1199 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 1200 return explore_numeric(pai, hostname, servname, res, hostname); 1201 #else 1202 const struct afd *afd; 1203 struct addrinfo *cur; 1204 int error; 1205 char *cp, *hostname2 = NULL, *scope, *addr; 1206 struct sockaddr_in6 *sin6; 1207 1208 /* 1209 * if the servname does not match socktype/protocol, ignore it. 1210 */ 1211 if (get_portmatch(pai, servname) != 0) 1212 return 0; 1213 1214 afd = find_afd(pai->ai_family); 1215 if (afd == NULL) 1216 return 0; 1217 1218 if (!afd->a_scoped) 1219 return explore_numeric(pai, hostname, servname, res, hostname); 1220 1221 cp = strchr(hostname, SCOPE_DELIMITER); 1222 if (cp == NULL) 1223 return explore_numeric(pai, hostname, servname, res, hostname); 1224 1225 /* 1226 * Handle special case of <scoped_address><delimiter><scope id> 1227 */ 1228 hostname2 = strdup(hostname); 1229 if (hostname2 == NULL) 1230 return EAI_MEMORY; 1231 /* terminate at the delimiter */ 1232 hostname2[cp - hostname] = '\0'; 1233 addr = hostname2; 1234 scope = cp + 1; 1235 1236 error = explore_numeric(pai, addr, servname, res, hostname); 1237 if (error == 0) { 1238 u_int32_t scopeid; 1239 1240 for (cur = *res; cur; cur = cur->ai_next) { 1241 if (cur->ai_family != AF_INET6) 1242 continue; 1243 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1244 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1245 free(hostname2); 1246 return(EAI_NONAME); /* XXX: is return OK? */ 1247 } 1248 sin6->sin6_scope_id = scopeid; 1249 } 1250 } 1251 1252 free(hostname2); 1253 1254 return error; 1255 #endif 1256 } 1257 1258 static int 1259 get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) 1260 { 1261 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1262 ai->ai_canonname = strdup(str); 1263 if (ai->ai_canonname == NULL) 1264 return EAI_MEMORY; 1265 } 1266 return 0; 1267 } 1268 1269 static struct addrinfo * 1270 get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) 1271 { 1272 char *p; 1273 struct addrinfo *ai; 1274 #ifdef FAITH 1275 struct in6_addr faith_prefix; 1276 char *fp_str; 1277 int translate = 0; 1278 #endif 1279 1280 #ifdef FAITH 1281 /* 1282 * Transfrom an IPv4 addr into a special IPv6 addr format for 1283 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1284 * 1285 * +-----------------------------------+------------+ 1286 * | faith prefix part (12 bytes) | embedded | 1287 * | | IPv4 addr part (4 bytes) 1288 * +-----------------------------------+------------+ 1289 * 1290 * faith prefix part is specified as ascii IPv6 addr format 1291 * in environmental variable GAI. 1292 * For FAITH to work correctly, routing to faith prefix must be 1293 * setup toward a machine where a FAITH daemon operates. 1294 * Also, the machine must enable some mechanizm 1295 * (e.g. faith interface hack) to divert those packet with 1296 * faith prefixed destination addr to user-land FAITH daemon. 1297 */ 1298 fp_str = getenv("GAI"); 1299 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1300 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1301 u_int32_t v4a; 1302 u_int8_t v4a_top; 1303 1304 memcpy(&v4a, addr, sizeof v4a); 1305 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1306 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1307 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1308 afd = &afdl[N_INET6]; 1309 memcpy(&faith_prefix.s6_addr[12], addr, 1310 sizeof(struct in_addr)); 1311 translate = 1; 1312 } 1313 } 1314 #endif 1315 1316 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1317 + (afd->a_socklen)); 1318 if (ai == NULL) 1319 return NULL; 1320 1321 memcpy(ai, pai, sizeof(struct addrinfo)); 1322 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1323 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1324 ai->ai_addr->sa_len = afd->a_socklen; 1325 ai->ai_addrlen = afd->a_socklen; 1326 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1327 p = (char *)(void *)(ai->ai_addr); 1328 #ifdef FAITH 1329 if (translate == 1) 1330 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1331 else 1332 #endif 1333 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1334 return ai; 1335 } 1336 1337 static int 1338 get_portmatch(const struct addrinfo *ai, const char *servname) 1339 { 1340 1341 /* get_port does not touch first argument when matchonly == 1. */ 1342 /* LINTED const cast */ 1343 return get_port((struct addrinfo *)ai, servname, 1); 1344 } 1345 1346 static int 1347 get_port(struct addrinfo *ai, const char *servname, int matchonly) 1348 { 1349 const char *proto; 1350 struct servent *sp; 1351 int port; 1352 int allownumeric; 1353 1354 if (servname == NULL) 1355 return 0; 1356 switch (ai->ai_family) { 1357 case AF_INET: 1358 #ifdef AF_INET6 1359 case AF_INET6: 1360 #endif 1361 break; 1362 default: 1363 return 0; 1364 } 1365 1366 switch (ai->ai_socktype) { 1367 case SOCK_RAW: 1368 return EAI_SERVICE; 1369 case SOCK_DGRAM: 1370 case SOCK_STREAM: 1371 allownumeric = 1; 1372 break; 1373 case ANY: 1374 allownumeric = 0; 1375 break; 1376 default: 1377 return EAI_SOCKTYPE; 1378 } 1379 1380 port = str2number(servname); 1381 if (port >= 0) { 1382 if (!allownumeric) 1383 return EAI_SERVICE; 1384 if (port < 0 || port > 65535) 1385 return EAI_SERVICE; 1386 port = htons(port); 1387 } else { 1388 if (ai->ai_flags & AI_NUMERICSERV) 1389 return EAI_NONAME; 1390 switch (ai->ai_socktype) { 1391 case SOCK_DGRAM: 1392 proto = "udp"; 1393 break; 1394 case SOCK_STREAM: 1395 proto = "tcp"; 1396 break; 1397 default: 1398 proto = NULL; 1399 break; 1400 } 1401 1402 if ((sp = getservbyname(servname, proto)) == NULL) 1403 return EAI_SERVICE; 1404 port = sp->s_port; 1405 } 1406 1407 if (!matchonly) { 1408 switch (ai->ai_family) { 1409 case AF_INET: 1410 ((struct sockaddr_in *)(void *) 1411 ai->ai_addr)->sin_port = port; 1412 break; 1413 #ifdef INET6 1414 case AF_INET6: 1415 ((struct sockaddr_in6 *)(void *) 1416 ai->ai_addr)->sin6_port = port; 1417 break; 1418 #endif 1419 } 1420 } 1421 1422 return 0; 1423 } 1424 1425 static const struct afd * 1426 find_afd(int af) 1427 { 1428 const struct afd *afd; 1429 1430 if (af == PF_UNSPEC) 1431 return NULL; 1432 for (afd = afdl; afd->a_af; afd++) { 1433 if (afd->a_af == af) 1434 return afd; 1435 } 1436 return NULL; 1437 } 1438 1439 /* 1440 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1441 * will take care of it. 1442 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1443 * if the code is right or not. 1444 * 1445 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1446 * _dns_getaddrinfo. 1447 */ 1448 static int 1449 addrconfig(struct addrinfo *pai) 1450 { 1451 int s, af; 1452 1453 /* 1454 * TODO: 1455 * Note that implementation dependent test for address 1456 * configuration should be done everytime called 1457 * (or apropriate interval), 1458 * because addresses will be dynamically assigned or deleted. 1459 */ 1460 af = pai->ai_family; 1461 if (af == AF_UNSPEC) { 1462 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1463 af = AF_INET; 1464 else { 1465 _close(s); 1466 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1467 af = AF_INET6; 1468 else 1469 _close(s); 1470 } 1471 } 1472 if (af != AF_UNSPEC) { 1473 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1474 return 0; 1475 _close(s); 1476 } 1477 pai->ai_family = af; 1478 return 1; 1479 } 1480 1481 #ifdef INET6 1482 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1483 static int 1484 ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid) 1485 { 1486 u_long lscopeid; 1487 struct in6_addr *a6; 1488 char *ep; 1489 1490 a6 = &sin6->sin6_addr; 1491 1492 /* empty scopeid portion is invalid */ 1493 if (*scope == '\0') 1494 return -1; 1495 1496 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1497 /* 1498 * We currently assume a one-to-one mapping between links 1499 * and interfaces, so we simply use interface indices for 1500 * like-local scopes. 1501 */ 1502 *scopeid = if_nametoindex(scope); 1503 if (*scopeid == 0) 1504 goto trynumeric; 1505 return 0; 1506 } 1507 1508 /* still unclear about literal, allow numeric only - placeholder */ 1509 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1510 goto trynumeric; 1511 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1512 goto trynumeric; 1513 else 1514 goto trynumeric; /* global */ 1515 1516 /* try to convert to a numeric id as a last resort */ 1517 trynumeric: 1518 errno = 0; 1519 lscopeid = strtoul(scope, &ep, 10); 1520 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1521 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1522 return 0; 1523 else 1524 return -1; 1525 } 1526 #endif 1527 1528 /* 1529 * FQDN hostname, DNS lookup 1530 */ 1531 static int 1532 explore_fqdn(const struct addrinfo *pai, const char *hostname, 1533 const char *servname, struct addrinfo **res) 1534 { 1535 struct addrinfo *result; 1536 struct addrinfo *cur; 1537 int error = 0; 1538 static const ns_dtab dtab[] = { 1539 NS_FILES_CB(_files_getaddrinfo, NULL) 1540 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1541 NS_NIS_CB(_yp_getaddrinfo, NULL) 1542 { 0 } 1543 }; 1544 1545 result = NULL; 1546 1547 /* 1548 * if the servname does not match socktype/protocol, ignore it. 1549 */ 1550 if (get_portmatch(pai, servname) != 0) 1551 return 0; 1552 1553 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1554 default_dns_files, hostname, pai)) { 1555 case NS_TRYAGAIN: 1556 error = EAI_AGAIN; 1557 goto free; 1558 case NS_UNAVAIL: 1559 error = EAI_FAIL; 1560 goto free; 1561 case NS_NOTFOUND: 1562 error = EAI_NONAME; 1563 goto free; 1564 case NS_SUCCESS: 1565 error = 0; 1566 for (cur = result; cur; cur = cur->ai_next) { 1567 GET_PORT(cur, servname); 1568 /* canonname should be filled already */ 1569 } 1570 break; 1571 } 1572 1573 *res = result; 1574 1575 return 0; 1576 1577 free: 1578 if (result) 1579 freeaddrinfo(result); 1580 return error; 1581 } 1582 1583 #ifdef DEBUG 1584 static const char AskedForGot[] = 1585 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1586 #endif 1587 1588 static struct addrinfo * 1589 getanswer(const querybuf *answer, int anslen, const char *qname, int qtype, 1590 const struct addrinfo *pai, res_state res) 1591 { 1592 struct addrinfo sentinel, *cur; 1593 struct addrinfo ai; 1594 const struct afd *afd; 1595 char *canonname; 1596 const HEADER *hp; 1597 const u_char *cp; 1598 int n; 1599 const u_char *eom; 1600 char *bp, *ep; 1601 int type, class, ancount, qdcount; 1602 int haveanswer, had_error; 1603 char tbuf[MAXDNAME]; 1604 int (*name_ok)(const char *); 1605 char hostbuf[8*1024]; 1606 1607 memset(&sentinel, 0, sizeof(sentinel)); 1608 cur = &sentinel; 1609 1610 canonname = NULL; 1611 eom = answer->buf + anslen; 1612 switch (qtype) { 1613 case T_A: 1614 case T_AAAA: 1615 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1616 name_ok = res_hnok; 1617 break; 1618 default: 1619 return (NULL); /* XXX should be abort(); */ 1620 } 1621 /* 1622 * find first satisfactory answer 1623 */ 1624 hp = &answer->hdr; 1625 ancount = ntohs(hp->ancount); 1626 qdcount = ntohs(hp->qdcount); 1627 bp = hostbuf; 1628 ep = hostbuf + sizeof hostbuf; 1629 cp = answer->buf + HFIXEDSZ; 1630 if (qdcount != 1) { 1631 RES_SET_H_ERRNO(res, NO_RECOVERY); 1632 return (NULL); 1633 } 1634 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1635 if ((n < 0) || !(*name_ok)(bp)) { 1636 RES_SET_H_ERRNO(res, NO_RECOVERY); 1637 return (NULL); 1638 } 1639 cp += n + QFIXEDSZ; 1640 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1641 /* res_send() has already verified that the query name is the 1642 * same as the one we sent; this just gets the expanded name 1643 * (i.e., with the succeeding search-domain tacked on). 1644 */ 1645 n = strlen(bp) + 1; /* for the \0 */ 1646 if (n >= MAXHOSTNAMELEN) { 1647 RES_SET_H_ERRNO(res, NO_RECOVERY); 1648 return (NULL); 1649 } 1650 canonname = bp; 1651 bp += n; 1652 /* The qname can be abbreviated, but h_name is now absolute. */ 1653 qname = canonname; 1654 } 1655 haveanswer = 0; 1656 had_error = 0; 1657 while (ancount-- > 0 && cp < eom && !had_error) { 1658 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1659 if ((n < 0) || !(*name_ok)(bp)) { 1660 had_error++; 1661 continue; 1662 } 1663 cp += n; /* name */ 1664 type = _getshort(cp); 1665 cp += INT16SZ; /* type */ 1666 class = _getshort(cp); 1667 cp += INT16SZ + INT32SZ; /* class, TTL */ 1668 n = _getshort(cp); 1669 cp += INT16SZ; /* len */ 1670 if (class != C_IN) { 1671 /* XXX - debug? syslog? */ 1672 cp += n; 1673 continue; /* XXX - had_error++ ? */ 1674 } 1675 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1676 type == T_CNAME) { 1677 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1678 if ((n < 0) || !(*name_ok)(tbuf)) { 1679 had_error++; 1680 continue; 1681 } 1682 cp += n; 1683 /* Get canonical name. */ 1684 n = strlen(tbuf) + 1; /* for the \0 */ 1685 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1686 had_error++; 1687 continue; 1688 } 1689 strlcpy(bp, tbuf, ep - bp); 1690 canonname = bp; 1691 bp += n; 1692 continue; 1693 } 1694 if (qtype == T_ANY) { 1695 if (!(type == T_A || type == T_AAAA)) { 1696 cp += n; 1697 continue; 1698 } 1699 } else if (type != qtype) { 1700 #ifdef DEBUG 1701 if (type != T_KEY && type != T_SIG) 1702 syslog(LOG_NOTICE|LOG_AUTH, 1703 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1704 qname, p_class(C_IN), p_type(qtype), 1705 p_type(type)); 1706 #endif 1707 cp += n; 1708 continue; /* XXX - had_error++ ? */ 1709 } 1710 switch (type) { 1711 case T_A: 1712 case T_AAAA: 1713 if (strcasecmp(canonname, bp) != 0) { 1714 #ifdef DEBUG 1715 syslog(LOG_NOTICE|LOG_AUTH, 1716 AskedForGot, canonname, bp); 1717 #endif 1718 cp += n; 1719 continue; /* XXX - had_error++ ? */ 1720 } 1721 if (type == T_A && n != INADDRSZ) { 1722 cp += n; 1723 continue; 1724 } 1725 if (type == T_AAAA && n != IN6ADDRSZ) { 1726 cp += n; 1727 continue; 1728 } 1729 #ifdef FILTER_V4MAPPED 1730 if (type == T_AAAA) { 1731 struct in6_addr in6; 1732 memcpy(&in6, cp, sizeof(in6)); 1733 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1734 cp += n; 1735 continue; 1736 } 1737 } 1738 #endif 1739 if (!haveanswer) { 1740 int nn; 1741 1742 canonname = bp; 1743 nn = strlen(bp) + 1; /* for the \0 */ 1744 bp += nn; 1745 } 1746 1747 /* don't overwrite pai */ 1748 ai = *pai; 1749 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1750 afd = find_afd(ai.ai_family); 1751 if (afd == NULL) { 1752 cp += n; 1753 continue; 1754 } 1755 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1756 if (cur->ai_next == NULL) 1757 had_error++; 1758 while (cur && cur->ai_next) 1759 cur = cur->ai_next; 1760 cp += n; 1761 break; 1762 default: 1763 abort(); 1764 } 1765 if (!had_error) 1766 haveanswer++; 1767 } 1768 if (haveanswer) { 1769 #if defined(RESOLVSORT) 1770 /* 1771 * We support only IPv4 address for backward 1772 * compatibility against gethostbyname(3). 1773 */ 1774 if (res->nsort && qtype == T_A) { 1775 if (addr4sort(&sentinel, res) < 0) { 1776 freeaddrinfo(sentinel.ai_next); 1777 RES_SET_H_ERRNO(res, NO_RECOVERY); 1778 return NULL; 1779 } 1780 } 1781 #endif /*RESOLVSORT*/ 1782 if (!canonname) 1783 (void)get_canonname(pai, sentinel.ai_next, qname); 1784 else 1785 (void)get_canonname(pai, sentinel.ai_next, canonname); 1786 RES_SET_H_ERRNO(res, NETDB_SUCCESS); 1787 return sentinel.ai_next; 1788 } 1789 1790 RES_SET_H_ERRNO(res, NO_RECOVERY); 1791 return NULL; 1792 } 1793 1794 #ifdef RESOLVSORT 1795 struct addr_ptr { 1796 struct addrinfo *ai; 1797 int aval; 1798 }; 1799 1800 static int 1801 addr4sort(struct addrinfo *sentinel, res_state res) 1802 { 1803 struct addrinfo *ai; 1804 struct addr_ptr *addrs, addr; 1805 struct sockaddr_in *sin; 1806 int naddrs, i, j; 1807 int needsort = 0; 1808 1809 if (!sentinel) 1810 return -1; 1811 naddrs = 0; 1812 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1813 naddrs++; 1814 if (naddrs < 2) 1815 return 0; /* We don't need sorting. */ 1816 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1817 return -1; 1818 i = 0; 1819 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1820 sin = (struct sockaddr_in *)ai->ai_addr; 1821 for (j = 0; (unsigned)j < res->nsort; j++) { 1822 if (res->sort_list[j].addr.s_addr == 1823 (sin->sin_addr.s_addr & res->sort_list[j].mask)) 1824 break; 1825 } 1826 addrs[i].ai = ai; 1827 addrs[i].aval = j; 1828 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1829 needsort = i; 1830 i++; 1831 } 1832 if (!needsort) { 1833 free(addrs); 1834 return 0; 1835 } 1836 1837 while (needsort < naddrs) { 1838 for (j = needsort - 1; j >= 0; j--) { 1839 if (addrs[j].aval > addrs[j+1].aval) { 1840 addr = addrs[j]; 1841 addrs[j] = addrs[j + 1]; 1842 addrs[j + 1] = addr; 1843 } else 1844 break; 1845 } 1846 needsort++; 1847 } 1848 1849 ai = sentinel; 1850 for (i = 0; i < naddrs; ++i) { 1851 ai->ai_next = addrs[i].ai; 1852 ai = ai->ai_next; 1853 } 1854 ai->ai_next = NULL; 1855 free(addrs); 1856 return 0; 1857 } 1858 #endif /*RESOLVSORT*/ 1859 1860 /*ARGSUSED*/ 1861 static int 1862 _dns_getaddrinfo(void *rv, void *cb_data, va_list ap) 1863 { 1864 struct addrinfo *ai; 1865 querybuf *buf, *buf2; 1866 const char *hostname; 1867 const struct addrinfo *pai; 1868 struct addrinfo sentinel, *cur; 1869 struct res_target q, q2; 1870 res_state res; 1871 1872 hostname = va_arg(ap, char *); 1873 pai = va_arg(ap, const struct addrinfo *); 1874 1875 memset(&q, 0, sizeof(q)); 1876 memset(&q2, 0, sizeof(q2)); 1877 memset(&sentinel, 0, sizeof(sentinel)); 1878 cur = &sentinel; 1879 1880 buf = malloc(sizeof(*buf)); 1881 if (!buf) { 1882 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 1883 return NS_NOTFOUND; 1884 } 1885 buf2 = malloc(sizeof(*buf2)); 1886 if (!buf2) { 1887 free(buf); 1888 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 1889 return NS_NOTFOUND; 1890 } 1891 1892 switch (pai->ai_family) { 1893 case AF_UNSPEC: 1894 q.name = hostname; 1895 q.qclass = C_IN; 1896 q.qtype = T_A; 1897 q.answer = buf->buf; 1898 q.anslen = sizeof(buf->buf); 1899 q.next = &q2; 1900 q2.name = hostname; 1901 q2.qclass = C_IN; 1902 q2.qtype = T_AAAA; 1903 q2.answer = buf2->buf; 1904 q2.anslen = sizeof(buf2->buf); 1905 break; 1906 case AF_INET: 1907 q.name = hostname; 1908 q.qclass = C_IN; 1909 q.qtype = T_A; 1910 q.answer = buf->buf; 1911 q.anslen = sizeof(buf->buf); 1912 break; 1913 case AF_INET6: 1914 q.name = hostname; 1915 q.qclass = C_IN; 1916 q.qtype = T_AAAA; 1917 q.answer = buf->buf; 1918 q.anslen = sizeof(buf->buf); 1919 break; 1920 default: 1921 free(buf); 1922 free(buf2); 1923 return NS_UNAVAIL; 1924 } 1925 1926 res = __res_state(); 1927 if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) { 1928 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 1929 free(buf); 1930 free(buf2); 1931 return NS_NOTFOUND; 1932 } 1933 1934 if (res_searchN(hostname, &q, res) < 0) { 1935 free(buf); 1936 free(buf2); 1937 return NS_NOTFOUND; 1938 } 1939 /* prefer IPv6 */ 1940 if (q.next) { 1941 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res); 1942 if (ai) { 1943 cur->ai_next = ai; 1944 while (cur && cur->ai_next) 1945 cur = cur->ai_next; 1946 } 1947 } 1948 ai = getanswer(buf, q.n, q.name, q.qtype, pai, res); 1949 if (ai) 1950 cur->ai_next = ai; 1951 free(buf); 1952 free(buf2); 1953 if (sentinel.ai_next == NULL) 1954 switch (res->res_h_errno) { 1955 case HOST_NOT_FOUND: 1956 return NS_NOTFOUND; 1957 case TRY_AGAIN: 1958 return NS_TRYAGAIN; 1959 default: 1960 return NS_UNAVAIL; 1961 } 1962 *((struct addrinfo **)rv) = sentinel.ai_next; 1963 return NS_SUCCESS; 1964 } 1965 1966 static void 1967 _sethtent(FILE **hostf) 1968 { 1969 if (!*hostf) 1970 *hostf = fopen(_PATH_HOSTS, "r"); 1971 else 1972 rewind(*hostf); 1973 } 1974 1975 static void 1976 _endhtent(FILE **hostf) 1977 { 1978 if (*hostf) { 1979 (void) fclose(*hostf); 1980 *hostf = NULL; 1981 } 1982 } 1983 1984 static struct addrinfo * 1985 _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 1986 { 1987 char *p; 1988 char *cp, *tname, *cname; 1989 struct addrinfo hints, *res0, *res; 1990 int error; 1991 const char *addr; 1992 char hostbuf[8*1024]; 1993 1994 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "r"))) 1995 return (NULL); 1996 again: 1997 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 1998 return (NULL); 1999 if (*p == '#') 2000 goto again; 2001 cp = strpbrk(p, "#\n"); 2002 if (cp != NULL) 2003 *cp = '\0'; 2004 if (!(cp = strpbrk(p, " \t"))) 2005 goto again; 2006 *cp++ = '\0'; 2007 addr = p; 2008 cname = NULL; 2009 /* if this is not something we're looking for, skip it. */ 2010 while (cp && *cp) { 2011 if (*cp == ' ' || *cp == '\t') { 2012 cp++; 2013 continue; 2014 } 2015 tname = cp; 2016 if (cname == NULL) 2017 cname = cp; 2018 if ((cp = strpbrk(cp, " \t")) != NULL) 2019 *cp++ = '\0'; 2020 if (strcasecmp(name, tname) == 0) 2021 goto found; 2022 } 2023 goto again; 2024 2025 found: 2026 /* we should not glob socktype/protocol here */ 2027 memset(&hints, 0, sizeof(hints)); 2028 hints.ai_family = pai->ai_family; 2029 hints.ai_socktype = SOCK_DGRAM; 2030 hints.ai_protocol = 0; 2031 hints.ai_flags = AI_NUMERICHOST; 2032 error = getaddrinfo(addr, "0", &hints, &res0); 2033 if (error) 2034 goto again; 2035 #ifdef FILTER_V4MAPPED 2036 /* XXX should check all items in the chain */ 2037 if (res0->ai_family == AF_INET6 && 2038 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2039 freeaddrinfo(res0); 2040 goto again; 2041 } 2042 #endif 2043 for (res = res0; res; res = res->ai_next) { 2044 /* cover it up */ 2045 res->ai_flags = pai->ai_flags; 2046 res->ai_socktype = pai->ai_socktype; 2047 res->ai_protocol = pai->ai_protocol; 2048 2049 if (pai->ai_flags & AI_CANONNAME) { 2050 if (get_canonname(pai, res, cname) != 0) { 2051 freeaddrinfo(res0); 2052 goto again; 2053 } 2054 } 2055 } 2056 return res0; 2057 } 2058 2059 /*ARGSUSED*/ 2060 static int 2061 _files_getaddrinfo(void *rv, void *cb_data, va_list ap) 2062 { 2063 const char *name; 2064 const struct addrinfo *pai; 2065 struct addrinfo sentinel, *cur; 2066 struct addrinfo *p; 2067 FILE *hostf = NULL; 2068 2069 name = va_arg(ap, char *); 2070 pai = va_arg(ap, struct addrinfo *); 2071 2072 memset(&sentinel, 0, sizeof(sentinel)); 2073 cur = &sentinel; 2074 2075 _sethtent(&hostf); 2076 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2077 cur->ai_next = p; 2078 while (cur && cur->ai_next) 2079 cur = cur->ai_next; 2080 } 2081 _endhtent(&hostf); 2082 2083 *((struct addrinfo **)rv) = sentinel.ai_next; 2084 if (sentinel.ai_next == NULL) 2085 return NS_NOTFOUND; 2086 return NS_SUCCESS; 2087 } 2088 2089 #ifdef YP 2090 /*ARGSUSED*/ 2091 static struct addrinfo * 2092 _yphostent(char *line, const struct addrinfo *pai) 2093 { 2094 struct addrinfo sentinel, *cur; 2095 struct addrinfo hints, *res, *res0; 2096 int error; 2097 char *p = line; 2098 const char *addr, *canonname; 2099 char *nextline; 2100 char *cp; 2101 2102 addr = canonname = NULL; 2103 2104 memset(&sentinel, 0, sizeof(sentinel)); 2105 cur = &sentinel; 2106 2107 nextline: 2108 /* terminate line */ 2109 cp = strchr(p, '\n'); 2110 if (cp) { 2111 *cp++ = '\0'; 2112 nextline = cp; 2113 } else 2114 nextline = NULL; 2115 2116 cp = strpbrk(p, " \t"); 2117 if (cp == NULL) { 2118 if (canonname == NULL) 2119 return (NULL); 2120 else 2121 goto done; 2122 } 2123 *cp++ = '\0'; 2124 2125 addr = p; 2126 2127 while (cp && *cp) { 2128 if (*cp == ' ' || *cp == '\t') { 2129 cp++; 2130 continue; 2131 } 2132 if (!canonname) 2133 canonname = cp; 2134 if ((cp = strpbrk(cp, " \t")) != NULL) 2135 *cp++ = '\0'; 2136 } 2137 2138 hints = *pai; 2139 hints.ai_flags = AI_NUMERICHOST; 2140 error = getaddrinfo(addr, NULL, &hints, &res0); 2141 if (error == 0) { 2142 for (res = res0; res; res = res->ai_next) { 2143 /* cover it up */ 2144 res->ai_flags = pai->ai_flags; 2145 2146 if (pai->ai_flags & AI_CANONNAME) 2147 (void)get_canonname(pai, res, canonname); 2148 } 2149 } else 2150 res0 = NULL; 2151 if (res0) { 2152 cur->ai_next = res0; 2153 while (cur && cur->ai_next) 2154 cur = cur->ai_next; 2155 } 2156 2157 if (nextline) { 2158 p = nextline; 2159 goto nextline; 2160 } 2161 2162 done: 2163 return sentinel.ai_next; 2164 } 2165 2166 /*ARGSUSED*/ 2167 static int 2168 _yp_getaddrinfo(void *rv, void *cb_data, va_list ap) 2169 { 2170 struct addrinfo sentinel, *cur; 2171 struct addrinfo *ai = NULL; 2172 char *ypbuf; 2173 int ypbuflen, r; 2174 const char *name; 2175 const struct addrinfo *pai; 2176 char *ypdomain; 2177 2178 if (_yp_check(&ypdomain) == 0) 2179 return NS_UNAVAIL; 2180 2181 name = va_arg(ap, char *); 2182 pai = va_arg(ap, const struct addrinfo *); 2183 2184 memset(&sentinel, 0, sizeof(sentinel)); 2185 cur = &sentinel; 2186 2187 /* hosts.byname is only for IPv4 (Solaris8) */ 2188 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2189 r = yp_match(ypdomain, "hosts.byname", name, 2190 (int)strlen(name), &ypbuf, &ypbuflen); 2191 if (r == 0) { 2192 struct addrinfo ai4; 2193 2194 ai4 = *pai; 2195 ai4.ai_family = AF_INET; 2196 ai = _yphostent(ypbuf, &ai4); 2197 if (ai) { 2198 cur->ai_next = ai; 2199 while (cur && cur->ai_next) 2200 cur = cur->ai_next; 2201 } 2202 free(ypbuf); 2203 } 2204 } 2205 2206 /* ipnodes.byname can hold both IPv4/v6 */ 2207 r = yp_match(ypdomain, "ipnodes.byname", name, 2208 (int)strlen(name), &ypbuf, &ypbuflen); 2209 if (r == 0) { 2210 ai = _yphostent(ypbuf, pai); 2211 if (ai) 2212 cur->ai_next = ai; 2213 free(ypbuf); 2214 } 2215 2216 if (sentinel.ai_next == NULL) { 2217 RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND); 2218 return NS_NOTFOUND; 2219 } 2220 *((struct addrinfo **)rv) = sentinel.ai_next; 2221 return NS_SUCCESS; 2222 } 2223 #endif 2224 2225 /* resolver logic */ 2226 2227 /* 2228 * Formulate a normal query, send, and await answer. 2229 * Returned answer is placed in supplied buffer "answer". 2230 * Perform preliminary check of answer, returning success only 2231 * if no error is indicated and the answer count is nonzero. 2232 * Return the size of the response on success, -1 on error. 2233 * Error number is left in h_errno. 2234 * 2235 * Caller must parse answer and determine whether it answers the question. 2236 */ 2237 static int 2238 res_queryN(const char *name, struct res_target *target, res_state res) 2239 { 2240 u_char *buf; 2241 HEADER *hp; 2242 int n; 2243 u_int oflags; 2244 struct res_target *t; 2245 int rcode; 2246 int ancount; 2247 2248 rcode = NOERROR; 2249 ancount = 0; 2250 2251 buf = malloc(MAXPACKET); 2252 if (!buf) { 2253 RES_SET_H_ERRNO(res, NETDB_INTERNAL); 2254 return -1; 2255 } 2256 2257 for (t = target; t; t = t->next) { 2258 int class, type; 2259 u_char *answer; 2260 int anslen; 2261 2262 hp = (HEADER *)(void *)t->answer; 2263 2264 /* make it easier... */ 2265 class = t->qclass; 2266 type = t->qtype; 2267 answer = t->answer; 2268 anslen = t->anslen; 2269 2270 oflags = res->_flags; 2271 2272 again: 2273 hp->rcode = NOERROR; /* default */ 2274 2275 #ifdef DEBUG 2276 if (res->options & RES_DEBUG) 2277 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2278 #endif 2279 2280 n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL, 2281 buf, MAXPACKET); 2282 if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 && 2283 (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U) 2284 n = res_nopt(res, n, buf, MAXPACKET, anslen); 2285 if (n <= 0) { 2286 #ifdef DEBUG 2287 if (res->options & RES_DEBUG) 2288 printf(";; res_query: mkquery failed\n"); 2289 #endif 2290 free(buf); 2291 RES_SET_H_ERRNO(res, NO_RECOVERY); 2292 return (n); 2293 } 2294 n = res_nsend(res, buf, n, answer, anslen); 2295 if (n < 0) { 2296 /* 2297 * if the query choked with EDNS0, retry 2298 * without EDNS0 2299 */ 2300 if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) 2301 != 0U && 2302 ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) { 2303 res->_flags |= RES_F_EDNS0ERR; 2304 if (res->options & RES_DEBUG) 2305 printf(";; res_nquery: retry without EDNS0\n"); 2306 goto again; 2307 } 2308 rcode = hp->rcode; /* record most recent error */ 2309 #ifdef DEBUG 2310 if (res->options & RES_DEBUG) 2311 printf(";; res_query: send error\n"); 2312 #endif 2313 continue; 2314 } 2315 2316 if (n > anslen) 2317 hp->rcode = FORMERR; /* XXX not very informative */ 2318 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2319 rcode = hp->rcode; /* record most recent error */ 2320 #ifdef DEBUG 2321 if (res->options & RES_DEBUG) 2322 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2323 ntohs(hp->ancount)); 2324 #endif 2325 continue; 2326 } 2327 2328 ancount += ntohs(hp->ancount); 2329 2330 t->n = n; 2331 } 2332 2333 free(buf); 2334 2335 if (ancount == 0) { 2336 switch (rcode) { 2337 case NXDOMAIN: 2338 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); 2339 break; 2340 case SERVFAIL: 2341 RES_SET_H_ERRNO(res, TRY_AGAIN); 2342 break; 2343 case NOERROR: 2344 RES_SET_H_ERRNO(res, NO_DATA); 2345 break; 2346 case FORMERR: 2347 case NOTIMP: 2348 case REFUSED: 2349 default: 2350 RES_SET_H_ERRNO(res, NO_RECOVERY); 2351 break; 2352 } 2353 return (-1); 2354 } 2355 return (ancount); 2356 } 2357 2358 /* 2359 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2360 * Return the size of the response on success, -1 on error. 2361 * If enabled, implement search rules until answer or unrecoverable failure 2362 * is detected. Error code, if any, is left in h_errno. 2363 */ 2364 static int 2365 res_searchN(const char *name, struct res_target *target, res_state res) 2366 { 2367 const char *cp, * const *domain; 2368 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2369 u_int dots; 2370 int trailing_dot, ret, saved_herrno; 2371 int got_nodata = 0, got_servfail = 0, root_on_list = 0; 2372 int tried_as_is = 0; 2373 int searched = 0; 2374 char abuf[MAXDNAME]; 2375 2376 errno = 0; 2377 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */ 2378 dots = 0; 2379 for (cp = name; *cp; cp++) 2380 dots += (*cp == '.'); 2381 trailing_dot = 0; 2382 if (cp > name && *--cp == '.') 2383 trailing_dot++; 2384 2385 /* 2386 * if there aren't any dots, it could be a user-level alias 2387 */ 2388 if (!dots && 2389 (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL) 2390 return (res_queryN(cp, target, res)); 2391 2392 /* 2393 * If there are enough dots in the name, let's just give it a 2394 * try 'as is'. The threshold can be set with the "ndots" option. 2395 * Also, query 'as is', if there is a trailing dot in the name. 2396 */ 2397 saved_herrno = -1; 2398 if (dots >= res->ndots || trailing_dot) { 2399 ret = res_querydomainN(name, NULL, target, res); 2400 if (ret > 0 || trailing_dot) 2401 return (ret); 2402 if (errno == ECONNREFUSED) { 2403 RES_SET_H_ERRNO(res, TRY_AGAIN); 2404 return (-1); 2405 } 2406 switch (res->res_h_errno) { 2407 case NO_DATA: 2408 case HOST_NOT_FOUND: 2409 break; 2410 case TRY_AGAIN: 2411 if (hp->rcode == SERVFAIL) 2412 break; 2413 /* FALLTHROUGH */ 2414 default: 2415 return (-1); 2416 } 2417 saved_herrno = res->res_h_errno; 2418 tried_as_is++; 2419 } 2420 2421 /* 2422 * We do at least one level of search if 2423 * - there is no dot and RES_DEFNAME is set, or 2424 * - there is at least one dot, there is no trailing dot, 2425 * and RES_DNSRCH is set. 2426 */ 2427 if ((!dots && (res->options & RES_DEFNAMES)) || 2428 (dots && !trailing_dot && (res->options & RES_DNSRCH))) { 2429 int done = 0; 2430 2431 for (domain = (const char * const *)res->dnsrch; 2432 *domain && !done; 2433 domain++) { 2434 searched = 1; 2435 2436 if (domain[0][0] == '\0' || 2437 (domain[0][0] == '.' && domain[0][1] == '\0')) 2438 root_on_list++; 2439 2440 if (root_on_list && tried_as_is) 2441 continue; 2442 2443 ret = res_querydomainN(name, *domain, target, res); 2444 if (ret > 0) 2445 return (ret); 2446 2447 /* 2448 * If no server present, give up. 2449 * If name isn't found in this domain, 2450 * keep trying higher domains in the search list 2451 * (if that's enabled). 2452 * On a NO_DATA error, keep trying, otherwise 2453 * a wildcard entry of another type could keep us 2454 * from finding this entry higher in the domain. 2455 * If we get some other error (negative answer or 2456 * server failure), then stop searching up, 2457 * but try the input name below in case it's 2458 * fully-qualified. 2459 */ 2460 if (errno == ECONNREFUSED) { 2461 RES_SET_H_ERRNO(res, TRY_AGAIN); 2462 return (-1); 2463 } 2464 2465 switch (res->res_h_errno) { 2466 case NO_DATA: 2467 got_nodata++; 2468 /* FALLTHROUGH */ 2469 case HOST_NOT_FOUND: 2470 /* keep trying */ 2471 break; 2472 case TRY_AGAIN: 2473 got_servfail++; 2474 if (hp->rcode == SERVFAIL) { 2475 /* try next search element, if any */ 2476 break; 2477 } 2478 /* FALLTHROUGH */ 2479 default: 2480 /* anything else implies that we're done */ 2481 done++; 2482 } 2483 /* 2484 * if we got here for some reason other than DNSRCH, 2485 * we only wanted one iteration of the loop, so stop. 2486 */ 2487 if (!(res->options & RES_DNSRCH)) 2488 done++; 2489 } 2490 } 2491 2492 switch (res->res_h_errno) { 2493 case NO_DATA: 2494 case HOST_NOT_FOUND: 2495 break; 2496 case TRY_AGAIN: 2497 if (hp->rcode == SERVFAIL) 2498 break; 2499 /* FALLTHROUGH */ 2500 default: 2501 goto giveup; 2502 } 2503 2504 /* 2505 * If the query has not already been tried as is then try it 2506 * unless RES_NOTLDQUERY is set and there were no dots. 2507 */ 2508 if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) && 2509 !(tried_as_is || root_on_list)) { 2510 ret = res_querydomainN(name, NULL, target, res); 2511 if (ret > 0) 2512 return (ret); 2513 } 2514 2515 /* 2516 * if we got here, we didn't satisfy the search. 2517 * if we did an initial full query, return that query's h_errno 2518 * (note that we wouldn't be here if that query had succeeded). 2519 * else if we ever got a nodata, send that back as the reason. 2520 * else send back meaningless h_errno, that being the one from 2521 * the last DNSRCH we did. 2522 */ 2523 giveup: 2524 if (saved_herrno != -1) 2525 RES_SET_H_ERRNO(res, saved_herrno); 2526 else if (got_nodata) 2527 RES_SET_H_ERRNO(res, NO_DATA); 2528 else if (got_servfail) 2529 RES_SET_H_ERRNO(res, TRY_AGAIN); 2530 return (-1); 2531 } 2532 2533 /* 2534 * Perform a call on res_query on the concatenation of name and domain, 2535 * removing a trailing dot from name if domain is NULL. 2536 */ 2537 static int 2538 res_querydomainN(const char *name, const char *domain, 2539 struct res_target *target, res_state res) 2540 { 2541 char nbuf[MAXDNAME]; 2542 const char *longname = nbuf; 2543 size_t n, d; 2544 2545 #ifdef DEBUG 2546 if (res->options & RES_DEBUG) 2547 printf(";; res_querydomain(%s, %s)\n", 2548 name, domain?domain:"<Nil>"); 2549 #endif 2550 if (domain == NULL) { 2551 /* 2552 * Check for trailing '.'; 2553 * copy without '.' if present. 2554 */ 2555 n = strlen(name); 2556 if (n >= MAXDNAME) { 2557 RES_SET_H_ERRNO(res, NO_RECOVERY); 2558 return (-1); 2559 } 2560 if (n > 0 && name[--n] == '.') { 2561 strncpy(nbuf, name, n); 2562 nbuf[n] = '\0'; 2563 } else 2564 longname = name; 2565 } else { 2566 n = strlen(name); 2567 d = strlen(domain); 2568 if (n + d + 1 >= MAXDNAME) { 2569 RES_SET_H_ERRNO(res, NO_RECOVERY); 2570 return (-1); 2571 } 2572 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2573 } 2574 return (res_queryN(longname, target, res)); 2575 } 2576