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 int 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 *); 269 #if defined(RESOLVSORT) 270 static int addr4sort(struct addrinfo *); 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 *); 284 static int res_searchN(const char *, struct res_target *); 285 static int res_querydomainN(const char *, const char *, 286 struct res_target *); 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(ai) 331 struct addrinfo *ai; 332 { 333 struct addrinfo *next; 334 335 do { 336 next = ai->ai_next; 337 if (ai->ai_canonname) 338 free(ai->ai_canonname); 339 /* no need to free(ai->ai_addr) */ 340 free(ai); 341 ai = next; 342 } while (ai); 343 } 344 345 static int 346 str2number(p) 347 const char *p; 348 { 349 char *ep; 350 unsigned long v; 351 352 if (*p == '\0') 353 return -1; 354 ep = NULL; 355 errno = 0; 356 v = strtoul(p, &ep, 10); 357 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) 358 return v; 359 else 360 return -1; 361 } 362 363 int 364 getaddrinfo(hostname, servname, hints, res) 365 const char *hostname, *servname; 366 const struct addrinfo *hints; 367 struct addrinfo **res; 368 { 369 struct addrinfo sentinel; 370 struct addrinfo *cur; 371 int error = 0; 372 struct addrinfo ai; 373 struct addrinfo ai0; 374 struct addrinfo *pai; 375 const struct explore *ex; 376 int numeric = 0; 377 378 memset(&sentinel, 0, sizeof(sentinel)); 379 cur = &sentinel; 380 pai = &ai; 381 pai->ai_flags = 0; 382 pai->ai_family = PF_UNSPEC; 383 pai->ai_socktype = ANY; 384 pai->ai_protocol = ANY; 385 pai->ai_addrlen = 0; 386 pai->ai_canonname = NULL; 387 pai->ai_addr = NULL; 388 pai->ai_next = NULL; 389 390 if (hostname == NULL && servname == NULL) 391 return EAI_NONAME; 392 if (hints) { 393 /* error check for hints */ 394 if (hints->ai_addrlen || hints->ai_canonname || 395 hints->ai_addr || hints->ai_next) 396 ERR(EAI_BADHINTS); /* xxx */ 397 if (hints->ai_flags & ~AI_MASK) 398 ERR(EAI_BADFLAGS); 399 switch (hints->ai_family) { 400 case PF_UNSPEC: 401 case PF_INET: 402 #ifdef INET6 403 case PF_INET6: 404 #endif 405 break; 406 default: 407 ERR(EAI_FAMILY); 408 } 409 memcpy(pai, hints, sizeof(*pai)); 410 411 /* 412 * if both socktype/protocol are specified, check if they 413 * are meaningful combination. 414 */ 415 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 416 for (ex = explore; ex->e_af >= 0; ex++) { 417 if (pai->ai_family != ex->e_af) 418 continue; 419 if (ex->e_socktype == ANY) 420 continue; 421 if (ex->e_protocol == ANY) 422 continue; 423 if (pai->ai_socktype == ex->e_socktype && 424 pai->ai_protocol != ex->e_protocol) { 425 ERR(EAI_BADHINTS); 426 } 427 } 428 } 429 } 430 431 /* 432 * post-2553: AI_ALL and AI_V4MAPPED are effective only against 433 * AF_INET6 query. They need to be ignored if specified in other 434 * occassions. 435 */ 436 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 437 case AI_V4MAPPED: 438 case AI_ALL | AI_V4MAPPED: 439 if (pai->ai_family != AF_INET6) 440 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 441 break; 442 case AI_ALL: 443 #if 1 444 /* illegal */ 445 ERR(EAI_BADFLAGS); 446 #else 447 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 448 #endif 449 break; 450 } 451 452 /* 453 * check for special cases. (1) numeric servname is disallowed if 454 * socktype/protocol are left unspecified. (2) servname is disallowed 455 * for raw and other inet{,6} sockets. 456 */ 457 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 458 #ifdef PF_INET6 459 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 460 #endif 461 ) { 462 ai0 = *pai; /* backup *pai */ 463 464 if (pai->ai_family == PF_UNSPEC) { 465 #ifdef PF_INET6 466 pai->ai_family = PF_INET6; 467 #else 468 pai->ai_family = PF_INET; 469 #endif 470 } 471 error = get_portmatch(pai, servname); 472 if (error) 473 ERR(error); 474 475 *pai = ai0; 476 } 477 478 ai0 = *pai; 479 480 /* NULL hostname, or numeric hostname */ 481 for (ex = explore; ex->e_af >= 0; ex++) { 482 *pai = ai0; 483 484 /* PF_UNSPEC entries are prepared for DNS queries only */ 485 if (ex->e_af == PF_UNSPEC) 486 continue; 487 488 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 489 continue; 490 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 491 continue; 492 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 493 continue; 494 495 if (pai->ai_family == PF_UNSPEC) 496 pai->ai_family = ex->e_af; 497 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 498 pai->ai_socktype = ex->e_socktype; 499 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 500 pai->ai_protocol = ex->e_protocol; 501 502 if (hostname == NULL) 503 error = explore_null(pai, servname, &cur->ai_next); 504 else 505 error = explore_numeric_scope(pai, hostname, servname, 506 &cur->ai_next); 507 508 if (error) 509 goto free; 510 511 while (cur && cur->ai_next) 512 cur = cur->ai_next; 513 } 514 515 /* 516 * XXX 517 * If numreic representation of AF1 can be interpreted as FQDN 518 * representation of AF2, we need to think again about the code below. 519 */ 520 if (sentinel.ai_next) { 521 numeric = 1; 522 goto good; 523 } 524 525 if (hostname == NULL) 526 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 527 if (pai->ai_flags & AI_NUMERICHOST) 528 ERR(EAI_NONAME); 529 530 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 531 ERR(EAI_FAIL); 532 533 /* 534 * hostname as alphabetical name. 535 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 536 * outer loop by AFs. 537 */ 538 for (ex = explore; ex->e_af >= 0; ex++) { 539 *pai = ai0; 540 541 /* require exact match for family field */ 542 if (pai->ai_family != ex->e_af) 543 continue; 544 545 if (!MATCH(pai->ai_socktype, ex->e_socktype, 546 WILD_SOCKTYPE(ex))) { 547 continue; 548 } 549 if (!MATCH(pai->ai_protocol, ex->e_protocol, 550 WILD_PROTOCOL(ex))) { 551 continue; 552 } 553 554 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 555 pai->ai_socktype = ex->e_socktype; 556 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 557 pai->ai_protocol = ex->e_protocol; 558 559 error = explore_fqdn(pai, hostname, servname, 560 &cur->ai_next); 561 562 while (cur && cur->ai_next) 563 cur = cur->ai_next; 564 } 565 566 /* XXX inhibit errors if we have the result */ 567 if (sentinel.ai_next) 568 error = 0; 569 570 good: 571 /* 572 * ensure we return either: 573 * - error == 0, non-NULL *res 574 * - error != 0, NULL *res 575 */ 576 if (error == 0) { 577 if (sentinel.ai_next) { 578 /* 579 * If the returned entry is for an active connection, 580 * and the given name is not numeric, reorder the 581 * list, so that the application would try the list 582 * in the most efficient order. 583 */ 584 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 585 if (!numeric) 586 (void)reorder(&sentinel); 587 } 588 *res = sentinel.ai_next; 589 return SUCCESS; 590 } else 591 error = EAI_FAIL; 592 } 593 free: 594 bad: 595 if (sentinel.ai_next) 596 freeaddrinfo(sentinel.ai_next); 597 *res = NULL; 598 return error; 599 } 600 601 static int 602 reorder(sentinel) 603 struct addrinfo *sentinel; 604 { 605 struct addrinfo *ai, **aip; 606 struct ai_order *aio; 607 int i, n; 608 struct policyhead policyhead; 609 610 /* count the number of addrinfo elements for sorting. */ 611 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 612 ; 613 614 /* 615 * If the number is small enough, we can skip the reordering process. 616 */ 617 if (n <= 1) 618 return(n); 619 620 /* allocate a temporary array for sort and initialization of it. */ 621 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 622 return(n); /* give up reordering */ 623 memset(aio, 0, sizeof(*aio) * n); 624 625 /* retrieve address selection policy from the kernel */ 626 TAILQ_INIT(&policyhead); 627 if (!get_addrselectpolicy(&policyhead)) { 628 /* no policy is installed into kernel, we don't sort. */ 629 free(aio); 630 return (n); 631 } 632 633 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 634 aio[i].aio_ai = ai; 635 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 636 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 637 &policyhead); 638 set_source(&aio[i], &policyhead); 639 } 640 641 /* perform sorting. */ 642 qsort(aio, n, sizeof(*aio), comp_dst); 643 644 /* reorder the addrinfo chain. */ 645 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 646 *aip = aio[i].aio_ai; 647 aip = &aio[i].aio_ai->ai_next; 648 } 649 *aip = NULL; 650 651 /* cleanup and return */ 652 free(aio); 653 free_addrselectpolicy(&policyhead); 654 return(n); 655 } 656 657 static int 658 get_addrselectpolicy(head) 659 struct policyhead *head; 660 { 661 #ifdef INET6 662 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 663 size_t l; 664 char *buf; 665 struct in6_addrpolicy *pol, *ep; 666 667 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 668 return (0); 669 if ((buf = malloc(l)) == NULL) 670 return (0); 671 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 672 free(buf); 673 return (0); 674 } 675 676 ep = (struct in6_addrpolicy *)(buf + l); 677 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 678 struct policyqueue *new; 679 680 if ((new = malloc(sizeof(*new))) == NULL) { 681 free_addrselectpolicy(head); /* make the list empty */ 682 break; 683 } 684 new->pc_policy = *pol; 685 TAILQ_INSERT_TAIL(head, new, pc_entry); 686 } 687 688 free(buf); 689 return (1); 690 #else 691 return (0); 692 #endif 693 } 694 695 static void 696 free_addrselectpolicy(head) 697 struct policyhead *head; 698 { 699 struct policyqueue *ent, *nent; 700 701 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 702 nent = TAILQ_NEXT(ent, pc_entry); 703 TAILQ_REMOVE(head, ent, pc_entry); 704 free(ent); 705 } 706 } 707 708 static struct policyqueue * 709 match_addrselectpolicy(addr, head) 710 struct sockaddr *addr; 711 struct policyhead *head; 712 { 713 #ifdef INET6 714 struct policyqueue *ent, *bestent = NULL; 715 struct in6_addrpolicy *pol; 716 int matchlen, bestmatchlen = -1; 717 u_char *mp, *ep, *k, *p, m; 718 struct sockaddr_in6 key; 719 720 switch(addr->sa_family) { 721 case AF_INET6: 722 key = *(struct sockaddr_in6 *)addr; 723 break; 724 case AF_INET: 725 /* convert the address into IPv4-mapped IPv6 address. */ 726 memset(&key, 0, sizeof(key)); 727 key.sin6_family = AF_INET6; 728 key.sin6_len = sizeof(key); 729 key.sin6_addr.s6_addr[10] = 0xff; 730 key.sin6_addr.s6_addr[11] = 0xff; 731 memcpy(&key.sin6_addr.s6_addr[12], 732 &((struct sockaddr_in *)addr)->sin_addr, 4); 733 break; 734 default: 735 return(NULL); 736 } 737 738 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 739 pol = &ent->pc_policy; 740 matchlen = 0; 741 742 mp = (u_char *)&pol->addrmask.sin6_addr; 743 ep = mp + 16; /* XXX: scope field? */ 744 k = (u_char *)&key.sin6_addr; 745 p = (u_char *)&pol->addr.sin6_addr; 746 for (; mp < ep && *mp; mp++, k++, p++) { 747 m = *mp; 748 if ((*k & m) != *p) 749 goto next; /* not match */ 750 if (m == 0xff) /* short cut for a typical case */ 751 matchlen += 8; 752 else { 753 while (m >= 0x80) { 754 matchlen++; 755 m <<= 1; 756 } 757 } 758 } 759 760 /* matched. check if this is better than the current best. */ 761 if (matchlen > bestmatchlen) { 762 bestent = ent; 763 bestmatchlen = matchlen; 764 } 765 766 next: 767 continue; 768 } 769 770 return(bestent); 771 #else 772 return(NULL); 773 #endif 774 775 } 776 777 static void 778 set_source(aio, ph) 779 struct ai_order *aio; 780 struct policyhead *ph; 781 { 782 struct addrinfo ai = *aio->aio_ai; 783 struct sockaddr_storage ss; 784 int s, srclen; 785 786 /* set unspec ("no source is available"), just in case */ 787 aio->aio_srcsa.sa_family = AF_UNSPEC; 788 aio->aio_srcscope = -1; 789 790 switch(ai.ai_family) { 791 case AF_INET: 792 #ifdef INET6 793 case AF_INET6: 794 #endif 795 break; 796 default: /* ignore unsupported AFs explicitly */ 797 return; 798 } 799 800 /* XXX: make a dummy addrinfo to call connect() */ 801 ai.ai_socktype = SOCK_DGRAM; 802 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 803 ai.ai_next = NULL; 804 memset(&ss, 0, sizeof(ss)); 805 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 806 ai.ai_addr = (struct sockaddr *)&ss; 807 get_port(&ai, "1", 0); 808 809 /* open a socket to get the source address for the given dst */ 810 if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0) 811 return; /* give up */ 812 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 813 goto cleanup; 814 srclen = ai.ai_addrlen; 815 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 816 aio->aio_srcsa.sa_family = AF_UNSPEC; 817 goto cleanup; 818 } 819 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 820 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 821 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 822 #ifdef INET6 823 if (ai.ai_family == AF_INET6) { 824 struct in6_ifreq ifr6; 825 u_int32_t flags6; 826 827 /* XXX: interface name should not be hardcoded */ 828 strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name)); 829 memset(&ifr6, 0, sizeof(ifr6)); 830 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 831 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 832 flags6 = ifr6.ifr_ifru.ifru_flags6; 833 if ((flags6 & IN6_IFF_DEPRECATED)) 834 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 835 } 836 } 837 #endif 838 839 cleanup: 840 _close(s); 841 return; 842 } 843 844 static int 845 matchlen(src, dst) 846 struct sockaddr *src, *dst; 847 { 848 int match = 0; 849 u_char *s, *d; 850 u_char *lim, r; 851 int addrlen; 852 853 switch (src->sa_family) { 854 #ifdef INET6 855 case AF_INET6: 856 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 857 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 858 addrlen = sizeof(struct in6_addr); 859 lim = s + addrlen; 860 break; 861 #endif 862 case AF_INET: 863 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 864 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 865 addrlen = sizeof(struct in_addr); 866 lim = s + addrlen; 867 break; 868 default: 869 return(0); 870 } 871 872 while (s < lim) 873 if ((r = (*d++ ^ *s++)) != 0) { 874 while (r < addrlen * 8) { 875 match++; 876 r <<= 1; 877 } 878 break; 879 } else 880 match += 8; 881 return(match); 882 } 883 884 static int 885 comp_dst(arg1, arg2) 886 const void *arg1, *arg2; 887 { 888 const struct ai_order *dst1 = arg1, *dst2 = arg2; 889 890 /* 891 * Rule 1: Avoid unusable destinations. 892 * XXX: we currently do not consider if an appropriate route exists. 893 */ 894 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 895 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 896 return(-1); 897 } 898 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 899 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 900 return(1); 901 } 902 903 /* Rule 2: Prefer matching scope. */ 904 if (dst1->aio_dstscope == dst1->aio_srcscope && 905 dst2->aio_dstscope != dst2->aio_srcscope) { 906 return(-1); 907 } 908 if (dst1->aio_dstscope != dst1->aio_srcscope && 909 dst2->aio_dstscope == dst2->aio_srcscope) { 910 return(1); 911 } 912 913 /* Rule 3: Avoid deprecated addresses. */ 914 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 915 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 916 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 917 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 918 return(-1); 919 } 920 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 921 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 922 return(1); 923 } 924 } 925 926 /* Rule 4: Prefer home addresses. */ 927 /* XXX: not implemented yet */ 928 929 /* Rule 5: Prefer matching label. */ 930 #ifdef INET6 931 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 932 dst1->aio_srcpolicy->pc_policy.label == 933 dst1->aio_dstpolicy->pc_policy.label && 934 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 935 dst2->aio_srcpolicy->pc_policy.label != 936 dst2->aio_dstpolicy->pc_policy.label)) { 937 return(-1); 938 } 939 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 940 dst2->aio_srcpolicy->pc_policy.label == 941 dst2->aio_dstpolicy->pc_policy.label && 942 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 943 dst1->aio_srcpolicy->pc_policy.label != 944 dst1->aio_dstpolicy->pc_policy.label)) { 945 return(1); 946 } 947 #endif 948 949 /* Rule 6: Prefer higher precedence. */ 950 #ifdef INET6 951 if (dst1->aio_dstpolicy && 952 (dst2->aio_dstpolicy == NULL || 953 dst1->aio_dstpolicy->pc_policy.preced > 954 dst2->aio_dstpolicy->pc_policy.preced)) { 955 return(-1); 956 } 957 if (dst2->aio_dstpolicy && 958 (dst1->aio_dstpolicy == NULL || 959 dst2->aio_dstpolicy->pc_policy.preced > 960 dst1->aio_dstpolicy->pc_policy.preced)) { 961 return(1); 962 } 963 #endif 964 965 /* Rule 7: Prefer native transport. */ 966 /* XXX: not implemented yet */ 967 968 /* Rule 8: Prefer smaller scope. */ 969 if (dst1->aio_dstscope >= 0 && 970 dst1->aio_dstscope < dst2->aio_dstscope) { 971 return(-1); 972 } 973 if (dst2->aio_dstscope >= 0 && 974 dst2->aio_dstscope < dst1->aio_dstscope) { 975 return(1); 976 } 977 978 /* 979 * Rule 9: Use longest matching prefix. 980 * We compare the match length in a same AF only. 981 */ 982 if (dst1->aio_ai->ai_addr->sa_family == 983 dst2->aio_ai->ai_addr->sa_family) { 984 if (dst1->aio_matchlen > dst2->aio_matchlen) { 985 return(-1); 986 } 987 if (dst1->aio_matchlen < dst2->aio_matchlen) { 988 return(1); 989 } 990 } 991 992 /* Rule 10: Otherwise, leave the order unchanged. */ 993 return(-1); 994 } 995 996 /* 997 * Copy from scope.c. 998 * XXX: we should standardize the functions and link them as standard 999 * library. 1000 */ 1001 static int 1002 gai_addr2scopetype(sa) 1003 struct sockaddr *sa; 1004 { 1005 #ifdef INET6 1006 struct sockaddr_in6 *sa6; 1007 #endif 1008 struct sockaddr_in *sa4; 1009 1010 switch(sa->sa_family) { 1011 #ifdef INET6 1012 case AF_INET6: 1013 sa6 = (struct sockaddr_in6 *)sa; 1014 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1015 /* just use the scope field of the multicast address */ 1016 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1017 } 1018 /* 1019 * Unicast addresses: map scope type to corresponding scope 1020 * value defined for multcast addresses. 1021 * XXX: hardcoded scope type values are bad... 1022 */ 1023 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1024 return(1); /* node local scope */ 1025 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1026 return(2); /* link-local scope */ 1027 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1028 return(5); /* site-local scope */ 1029 return(14); /* global scope */ 1030 break; 1031 #endif 1032 case AF_INET: 1033 /* 1034 * IPv4 pseudo scoping according to RFC 3484. 1035 */ 1036 sa4 = (struct sockaddr_in *)sa; 1037 /* IPv4 autoconfiguration addresses have link-local scope. */ 1038 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1039 ((u_char *)&sa4->sin_addr)[1] == 254) 1040 return(2); 1041 /* Private addresses have site-local scope. */ 1042 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1043 (((u_char *)&sa4->sin_addr)[0] == 172 && 1044 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1045 (((u_char *)&sa4->sin_addr)[0] == 192 && 1046 ((u_char *)&sa4->sin_addr)[1] == 168)) 1047 return(14); /* XXX: It should be 5 unless NAT */ 1048 /* Loopback addresses have link-local scope. */ 1049 if (((u_char *)&sa4->sin_addr)[0] == 127) 1050 return(2); 1051 return(14); 1052 break; 1053 default: 1054 errno = EAFNOSUPPORT; /* is this a good error? */ 1055 return(-1); 1056 } 1057 } 1058 1059 /* 1060 * hostname == NULL. 1061 * passive socket -> anyaddr (0.0.0.0 or ::) 1062 * non-passive socket -> localhost (127.0.0.1 or ::1) 1063 */ 1064 static int 1065 explore_null(pai, servname, res) 1066 const struct addrinfo *pai; 1067 const char *servname; 1068 struct addrinfo **res; 1069 { 1070 int s; 1071 const struct afd *afd; 1072 struct addrinfo *cur; 1073 struct addrinfo sentinel; 1074 int error; 1075 1076 *res = NULL; 1077 sentinel.ai_next = NULL; 1078 cur = &sentinel; 1079 1080 /* 1081 * filter out AFs that are not supported by the kernel 1082 * XXX errno? 1083 */ 1084 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1085 if (s < 0) { 1086 if (errno != EMFILE) 1087 return 0; 1088 } else 1089 _close(s); 1090 1091 /* 1092 * if the servname does not match socktype/protocol, ignore it. 1093 */ 1094 if (get_portmatch(pai, servname) != 0) 1095 return 0; 1096 1097 afd = find_afd(pai->ai_family); 1098 if (afd == NULL) 1099 return 0; 1100 1101 if (pai->ai_flags & AI_PASSIVE) { 1102 GET_AI(cur->ai_next, afd, afd->a_addrany); 1103 /* xxx meaningless? 1104 * GET_CANONNAME(cur->ai_next, "anyaddr"); 1105 */ 1106 GET_PORT(cur->ai_next, servname); 1107 } else { 1108 GET_AI(cur->ai_next, afd, afd->a_loopback); 1109 /* xxx meaningless? 1110 * GET_CANONNAME(cur->ai_next, "localhost"); 1111 */ 1112 GET_PORT(cur->ai_next, servname); 1113 } 1114 cur = cur->ai_next; 1115 1116 *res = sentinel.ai_next; 1117 return 0; 1118 1119 free: 1120 if (sentinel.ai_next) 1121 freeaddrinfo(sentinel.ai_next); 1122 return error; 1123 } 1124 1125 /* 1126 * numeric hostname 1127 */ 1128 static int 1129 explore_numeric(pai, hostname, servname, res, canonname) 1130 const struct addrinfo *pai; 1131 const char *hostname; 1132 const char *servname; 1133 struct addrinfo **res; 1134 const char *canonname; 1135 { 1136 const struct afd *afd; 1137 struct addrinfo *cur; 1138 struct addrinfo sentinel; 1139 int error; 1140 char pton[PTON_MAX]; 1141 1142 *res = NULL; 1143 sentinel.ai_next = NULL; 1144 cur = &sentinel; 1145 1146 /* 1147 * if the servname does not match socktype/protocol, ignore it. 1148 */ 1149 if (get_portmatch(pai, servname) != 0) 1150 return 0; 1151 1152 afd = find_afd(pai->ai_family); 1153 if (afd == NULL) 1154 return 0; 1155 1156 switch (afd->a_af) { 1157 #if 1 /*X/Open spec*/ 1158 case AF_INET: 1159 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 1160 if (pai->ai_family == afd->a_af || 1161 pai->ai_family == PF_UNSPEC /*?*/) { 1162 GET_AI(cur->ai_next, afd, pton); 1163 GET_PORT(cur->ai_next, servname); 1164 if ((pai->ai_flags & AI_CANONNAME)) { 1165 /* 1166 * Set the numeric address itself as 1167 * the canonical name, based on a 1168 * clarification in rfc3493. 1169 */ 1170 GET_CANONNAME(cur->ai_next, canonname); 1171 } 1172 while (cur && cur->ai_next) 1173 cur = cur->ai_next; 1174 } else 1175 ERR(EAI_FAMILY); /*xxx*/ 1176 } 1177 break; 1178 #endif 1179 default: 1180 if (inet_pton(afd->a_af, hostname, pton) == 1) { 1181 if (pai->ai_family == afd->a_af || 1182 pai->ai_family == PF_UNSPEC /*?*/) { 1183 GET_AI(cur->ai_next, afd, pton); 1184 GET_PORT(cur->ai_next, servname); 1185 if ((pai->ai_flags & AI_CANONNAME)) { 1186 /* 1187 * Set the numeric address itself as 1188 * the canonical name, based on a 1189 * clarification in rfc3493. 1190 */ 1191 GET_CANONNAME(cur->ai_next, canonname); 1192 } 1193 while (cur && cur->ai_next) 1194 cur = cur->ai_next; 1195 } else 1196 ERR(EAI_FAMILY); /* XXX */ 1197 } 1198 break; 1199 } 1200 1201 *res = sentinel.ai_next; 1202 return 0; 1203 1204 free: 1205 bad: 1206 if (sentinel.ai_next) 1207 freeaddrinfo(sentinel.ai_next); 1208 return error; 1209 } 1210 1211 /* 1212 * numeric hostname with scope 1213 */ 1214 static int 1215 explore_numeric_scope(pai, hostname, servname, res) 1216 const struct addrinfo *pai; 1217 const char *hostname; 1218 const char *servname; 1219 struct addrinfo **res; 1220 { 1221 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 1222 return explore_numeric(pai, hostname, servname, res, hostname); 1223 #else 1224 const struct afd *afd; 1225 struct addrinfo *cur; 1226 int error; 1227 char *cp, *hostname2 = NULL, *scope, *addr; 1228 struct sockaddr_in6 *sin6; 1229 1230 /* 1231 * if the servname does not match socktype/protocol, ignore it. 1232 */ 1233 if (get_portmatch(pai, servname) != 0) 1234 return 0; 1235 1236 afd = find_afd(pai->ai_family); 1237 if (afd == NULL) 1238 return 0; 1239 1240 if (!afd->a_scoped) 1241 return explore_numeric(pai, hostname, servname, res, hostname); 1242 1243 cp = strchr(hostname, SCOPE_DELIMITER); 1244 if (cp == NULL) 1245 return explore_numeric(pai, hostname, servname, res, hostname); 1246 1247 /* 1248 * Handle special case of <scoped_address><delimiter><scope id> 1249 */ 1250 hostname2 = strdup(hostname); 1251 if (hostname2 == NULL) 1252 return EAI_MEMORY; 1253 /* terminate at the delimiter */ 1254 hostname2[cp - hostname] = '\0'; 1255 addr = hostname2; 1256 scope = cp + 1; 1257 1258 error = explore_numeric(pai, addr, servname, res, hostname); 1259 if (error == 0) { 1260 u_int32_t scopeid; 1261 1262 for (cur = *res; cur; cur = cur->ai_next) { 1263 if (cur->ai_family != AF_INET6) 1264 continue; 1265 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1266 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1267 free(hostname2); 1268 return(EAI_NONAME); /* XXX: is return OK? */ 1269 } 1270 sin6->sin6_scope_id = scopeid; 1271 } 1272 } 1273 1274 free(hostname2); 1275 1276 return error; 1277 #endif 1278 } 1279 1280 static int 1281 get_canonname(pai, ai, str) 1282 const struct addrinfo *pai; 1283 struct addrinfo *ai; 1284 const char *str; 1285 { 1286 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1287 ai->ai_canonname = strdup(str); 1288 if (ai->ai_canonname == NULL) 1289 return EAI_MEMORY; 1290 } 1291 return 0; 1292 } 1293 1294 static struct addrinfo * 1295 get_ai(pai, afd, addr) 1296 const struct addrinfo *pai; 1297 const struct afd *afd; 1298 const char *addr; 1299 { 1300 char *p; 1301 struct addrinfo *ai; 1302 #ifdef FAITH 1303 struct in6_addr faith_prefix; 1304 char *fp_str; 1305 int translate = 0; 1306 #endif 1307 1308 #ifdef FAITH 1309 /* 1310 * Transfrom an IPv4 addr into a special IPv6 addr format for 1311 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1312 * 1313 * +-----------------------------------+------------+ 1314 * | faith prefix part (12 bytes) | embedded | 1315 * | | IPv4 addr part (4 bytes) 1316 * +-----------------------------------+------------+ 1317 * 1318 * faith prefix part is specified as ascii IPv6 addr format 1319 * in environmental variable GAI. 1320 * For FAITH to work correctly, routing to faith prefix must be 1321 * setup toward a machine where a FAITH daemon operates. 1322 * Also, the machine must enable some mechanizm 1323 * (e.g. faith interface hack) to divert those packet with 1324 * faith prefixed destination addr to user-land FAITH daemon. 1325 */ 1326 fp_str = getenv("GAI"); 1327 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1328 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1329 u_int32_t v4a; 1330 u_int8_t v4a_top; 1331 1332 memcpy(&v4a, addr, sizeof v4a); 1333 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1334 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1335 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1336 afd = &afdl[N_INET6]; 1337 memcpy(&faith_prefix.s6_addr[12], addr, 1338 sizeof(struct in_addr)); 1339 translate = 1; 1340 } 1341 } 1342 #endif 1343 1344 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1345 + (afd->a_socklen)); 1346 if (ai == NULL) 1347 return NULL; 1348 1349 memcpy(ai, pai, sizeof(struct addrinfo)); 1350 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1351 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1352 ai->ai_addr->sa_len = afd->a_socklen; 1353 ai->ai_addrlen = afd->a_socklen; 1354 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1355 p = (char *)(void *)(ai->ai_addr); 1356 #ifdef FAITH 1357 if (translate == 1) 1358 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1359 else 1360 #endif 1361 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1362 return ai; 1363 } 1364 1365 static int 1366 get_portmatch(ai, servname) 1367 const struct addrinfo *ai; 1368 const char *servname; 1369 { 1370 1371 /* get_port does not touch first argument when matchonly == 1. */ 1372 /* LINTED const cast */ 1373 return get_port((struct addrinfo *)ai, servname, 1); 1374 } 1375 1376 static int 1377 get_port(ai, servname, matchonly) 1378 struct addrinfo *ai; 1379 const char *servname; 1380 int matchonly; 1381 { 1382 const char *proto; 1383 struct servent *sp; 1384 int port; 1385 int allownumeric; 1386 1387 if (servname == NULL) 1388 return 0; 1389 switch (ai->ai_family) { 1390 case AF_INET: 1391 #ifdef AF_INET6 1392 case AF_INET6: 1393 #endif 1394 break; 1395 default: 1396 return 0; 1397 } 1398 1399 switch (ai->ai_socktype) { 1400 case SOCK_RAW: 1401 return EAI_SERVICE; 1402 case SOCK_DGRAM: 1403 case SOCK_STREAM: 1404 allownumeric = 1; 1405 break; 1406 case ANY: 1407 allownumeric = 0; 1408 break; 1409 default: 1410 return EAI_SOCKTYPE; 1411 } 1412 1413 port = str2number(servname); 1414 if (port >= 0) { 1415 if (!allownumeric) 1416 return EAI_SERVICE; 1417 if (port < 0 || port > 65535) 1418 return EAI_SERVICE; 1419 port = htons(port); 1420 } else { 1421 if (ai->ai_flags & AI_NUMERICSERV) 1422 return EAI_NONAME; 1423 switch (ai->ai_socktype) { 1424 case SOCK_DGRAM: 1425 proto = "udp"; 1426 break; 1427 case SOCK_STREAM: 1428 proto = "tcp"; 1429 break; 1430 default: 1431 proto = NULL; 1432 break; 1433 } 1434 1435 if ((sp = getservbyname(servname, proto)) == NULL) 1436 return EAI_SERVICE; 1437 port = sp->s_port; 1438 } 1439 1440 if (!matchonly) { 1441 switch (ai->ai_family) { 1442 case AF_INET: 1443 ((struct sockaddr_in *)(void *) 1444 ai->ai_addr)->sin_port = port; 1445 break; 1446 #ifdef INET6 1447 case AF_INET6: 1448 ((struct sockaddr_in6 *)(void *) 1449 ai->ai_addr)->sin6_port = port; 1450 break; 1451 #endif 1452 } 1453 } 1454 1455 return 0; 1456 } 1457 1458 static const struct afd * 1459 find_afd(af) 1460 int af; 1461 { 1462 const struct afd *afd; 1463 1464 if (af == PF_UNSPEC) 1465 return NULL; 1466 for (afd = afdl; afd->a_af; afd++) { 1467 if (afd->a_af == af) 1468 return afd; 1469 } 1470 return NULL; 1471 } 1472 1473 /* 1474 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1475 * will take care of it. 1476 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1477 * if the code is right or not. 1478 * 1479 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1480 * _dns_getaddrinfo. 1481 */ 1482 static int 1483 addrconfig(pai) 1484 struct addrinfo *pai; 1485 { 1486 int s, af; 1487 1488 /* 1489 * TODO: 1490 * Note that implementation dependent test for address 1491 * configuration should be done everytime called 1492 * (or apropriate interval), 1493 * because addresses will be dynamically assigned or deleted. 1494 */ 1495 af = pai->ai_family; 1496 if (af == AF_UNSPEC) { 1497 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1498 af = AF_INET; 1499 else { 1500 _close(s); 1501 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1502 af = AF_INET6; 1503 else 1504 _close(s); 1505 } 1506 } 1507 if (af != AF_UNSPEC) { 1508 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1509 return 0; 1510 _close(s); 1511 } 1512 pai->ai_family = af; 1513 return 1; 1514 } 1515 1516 #ifdef INET6 1517 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1518 static int 1519 ip6_str2scopeid(scope, sin6, scopeid) 1520 char *scope; 1521 struct sockaddr_in6 *sin6; 1522 u_int32_t *scopeid; 1523 { 1524 u_long lscopeid; 1525 struct in6_addr *a6; 1526 char *ep; 1527 1528 a6 = &sin6->sin6_addr; 1529 1530 /* empty scopeid portion is invalid */ 1531 if (*scope == '\0') 1532 return -1; 1533 1534 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1535 /* 1536 * We currently assume a one-to-one mapping between links 1537 * and interfaces, so we simply use interface indices for 1538 * like-local scopes. 1539 */ 1540 *scopeid = if_nametoindex(scope); 1541 if (*scopeid == 0) 1542 goto trynumeric; 1543 return 0; 1544 } 1545 1546 /* still unclear about literal, allow numeric only - placeholder */ 1547 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1548 goto trynumeric; 1549 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1550 goto trynumeric; 1551 else 1552 goto trynumeric; /* global */ 1553 1554 /* try to convert to a numeric id as a last resort */ 1555 trynumeric: 1556 errno = 0; 1557 lscopeid = strtoul(scope, &ep, 10); 1558 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1559 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1560 return 0; 1561 else 1562 return -1; 1563 } 1564 #endif 1565 1566 /* 1567 * FQDN hostname, DNS lookup 1568 */ 1569 static int 1570 explore_fqdn(pai, hostname, servname, res) 1571 const struct addrinfo *pai; 1572 const char *hostname; 1573 const char *servname; 1574 struct addrinfo **res; 1575 { 1576 struct addrinfo *result; 1577 struct addrinfo *cur; 1578 int error = 0; 1579 static const ns_dtab dtab[] = { 1580 NS_FILES_CB(_files_getaddrinfo, NULL) 1581 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1582 NS_NIS_CB(_yp_getaddrinfo, NULL) 1583 { 0 } 1584 }; 1585 1586 result = NULL; 1587 1588 /* 1589 * if the servname does not match socktype/protocol, ignore it. 1590 */ 1591 if (get_portmatch(pai, servname) != 0) 1592 return 0; 1593 1594 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1595 default_dns_files, hostname, pai)) { 1596 case NS_TRYAGAIN: 1597 error = EAI_AGAIN; 1598 goto free; 1599 case NS_UNAVAIL: 1600 error = EAI_FAIL; 1601 goto free; 1602 case NS_NOTFOUND: 1603 error = EAI_NONAME; 1604 goto free; 1605 case NS_SUCCESS: 1606 error = 0; 1607 for (cur = result; cur; cur = cur->ai_next) { 1608 GET_PORT(cur, servname); 1609 /* canonname should be filled already */ 1610 } 1611 break; 1612 } 1613 1614 *res = result; 1615 1616 return 0; 1617 1618 free: 1619 if (result) 1620 freeaddrinfo(result); 1621 return error; 1622 } 1623 1624 #ifdef DEBUG 1625 static const char AskedForGot[] = 1626 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1627 #endif 1628 1629 static struct addrinfo * 1630 getanswer(answer, anslen, qname, qtype, pai) 1631 const querybuf *answer; 1632 int anslen; 1633 const char *qname; 1634 int qtype; 1635 const struct addrinfo *pai; 1636 { 1637 struct addrinfo sentinel, *cur; 1638 struct addrinfo ai; 1639 const struct afd *afd; 1640 char *canonname; 1641 const HEADER *hp; 1642 const u_char *cp; 1643 int n; 1644 const u_char *eom; 1645 char *bp, *ep; 1646 int type, class, ancount, qdcount; 1647 int haveanswer, had_error; 1648 char tbuf[MAXDNAME]; 1649 int (*name_ok)(const char *); 1650 char hostbuf[8*1024]; 1651 1652 memset(&sentinel, 0, sizeof(sentinel)); 1653 cur = &sentinel; 1654 1655 canonname = NULL; 1656 eom = answer->buf + anslen; 1657 switch (qtype) { 1658 case T_A: 1659 case T_AAAA: 1660 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1661 name_ok = res_hnok; 1662 break; 1663 default: 1664 return (NULL); /* XXX should be abort(); */ 1665 } 1666 /* 1667 * find first satisfactory answer 1668 */ 1669 hp = &answer->hdr; 1670 ancount = ntohs(hp->ancount); 1671 qdcount = ntohs(hp->qdcount); 1672 bp = hostbuf; 1673 ep = hostbuf + sizeof hostbuf; 1674 cp = answer->buf + HFIXEDSZ; 1675 if (qdcount != 1) { 1676 h_errno = NO_RECOVERY; 1677 return (NULL); 1678 } 1679 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1680 if ((n < 0) || !(*name_ok)(bp)) { 1681 h_errno = NO_RECOVERY; 1682 return (NULL); 1683 } 1684 cp += n + QFIXEDSZ; 1685 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1686 /* res_send() has already verified that the query name is the 1687 * same as the one we sent; this just gets the expanded name 1688 * (i.e., with the succeeding search-domain tacked on). 1689 */ 1690 n = strlen(bp) + 1; /* for the \0 */ 1691 if (n >= MAXHOSTNAMELEN) { 1692 h_errno = NO_RECOVERY; 1693 return (NULL); 1694 } 1695 canonname = bp; 1696 bp += n; 1697 /* The qname can be abbreviated, but h_name is now absolute. */ 1698 qname = canonname; 1699 } 1700 haveanswer = 0; 1701 had_error = 0; 1702 while (ancount-- > 0 && cp < eom && !had_error) { 1703 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1704 if ((n < 0) || !(*name_ok)(bp)) { 1705 had_error++; 1706 continue; 1707 } 1708 cp += n; /* name */ 1709 type = _getshort(cp); 1710 cp += INT16SZ; /* type */ 1711 class = _getshort(cp); 1712 cp += INT16SZ + INT32SZ; /* class, TTL */ 1713 n = _getshort(cp); 1714 cp += INT16SZ; /* len */ 1715 if (class != C_IN) { 1716 /* XXX - debug? syslog? */ 1717 cp += n; 1718 continue; /* XXX - had_error++ ? */ 1719 } 1720 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1721 type == T_CNAME) { 1722 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1723 if ((n < 0) || !(*name_ok)(tbuf)) { 1724 had_error++; 1725 continue; 1726 } 1727 cp += n; 1728 /* Get canonical name. */ 1729 n = strlen(tbuf) + 1; /* for the \0 */ 1730 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1731 had_error++; 1732 continue; 1733 } 1734 strlcpy(bp, tbuf, ep - bp); 1735 canonname = bp; 1736 bp += n; 1737 continue; 1738 } 1739 if (qtype == T_ANY) { 1740 if (!(type == T_A || type == T_AAAA)) { 1741 cp += n; 1742 continue; 1743 } 1744 } else if (type != qtype) { 1745 #ifdef DEBUG 1746 if (type != T_KEY && type != T_SIG) 1747 syslog(LOG_NOTICE|LOG_AUTH, 1748 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1749 qname, p_class(C_IN), p_type(qtype), 1750 p_type(type)); 1751 #endif 1752 cp += n; 1753 continue; /* XXX - had_error++ ? */ 1754 } 1755 switch (type) { 1756 case T_A: 1757 case T_AAAA: 1758 if (strcasecmp(canonname, bp) != 0) { 1759 #ifdef DEBUG 1760 syslog(LOG_NOTICE|LOG_AUTH, 1761 AskedForGot, canonname, bp); 1762 #endif 1763 cp += n; 1764 continue; /* XXX - had_error++ ? */ 1765 } 1766 if (type == T_A && n != INADDRSZ) { 1767 cp += n; 1768 continue; 1769 } 1770 if (type == T_AAAA && n != IN6ADDRSZ) { 1771 cp += n; 1772 continue; 1773 } 1774 #ifdef FILTER_V4MAPPED 1775 if (type == T_AAAA) { 1776 struct in6_addr in6; 1777 memcpy(&in6, cp, sizeof(in6)); 1778 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1779 cp += n; 1780 continue; 1781 } 1782 } 1783 #endif 1784 if (!haveanswer) { 1785 int nn; 1786 1787 canonname = bp; 1788 nn = strlen(bp) + 1; /* for the \0 */ 1789 bp += nn; 1790 } 1791 1792 /* don't overwrite pai */ 1793 ai = *pai; 1794 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1795 afd = find_afd(ai.ai_family); 1796 if (afd == NULL) { 1797 cp += n; 1798 continue; 1799 } 1800 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1801 if (cur->ai_next == NULL) 1802 had_error++; 1803 while (cur && cur->ai_next) 1804 cur = cur->ai_next; 1805 cp += n; 1806 break; 1807 default: 1808 abort(); 1809 } 1810 if (!had_error) 1811 haveanswer++; 1812 } 1813 if (haveanswer) { 1814 #if defined(RESOLVSORT) 1815 /* 1816 * We support only IPv4 address for backward 1817 * compatibility against gethostbyname(3). 1818 */ 1819 if (_res.nsort && qtype == T_A) { 1820 if (addr4sort(&sentinel) < 0) { 1821 freeaddrinfo(sentinel.ai_next); 1822 h_errno = NO_RECOVERY; 1823 return NULL; 1824 } 1825 } 1826 #endif /*RESOLVSORT*/ 1827 if (!canonname) 1828 (void)get_canonname(pai, sentinel.ai_next, qname); 1829 else 1830 (void)get_canonname(pai, sentinel.ai_next, canonname); 1831 h_errno = NETDB_SUCCESS; 1832 return sentinel.ai_next; 1833 } 1834 1835 h_errno = NO_RECOVERY; 1836 return NULL; 1837 } 1838 1839 #ifdef RESOLVSORT 1840 struct addr_ptr { 1841 struct addrinfo *ai; 1842 int aval; 1843 }; 1844 1845 static int 1846 addr4sort(struct addrinfo *sentinel) 1847 { 1848 struct addrinfo *ai; 1849 struct addr_ptr *addrs, addr; 1850 struct sockaddr_in *sin; 1851 int naddrs, i, j; 1852 int needsort = 0; 1853 1854 if (!sentinel) 1855 return -1; 1856 naddrs = 0; 1857 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1858 naddrs++; 1859 if (naddrs < 2) 1860 return 0; /* We don't need sorting. */ 1861 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1862 return -1; 1863 i = 0; 1864 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1865 sin = (struct sockaddr_in *)ai->ai_addr; 1866 for (j = 0; (unsigned)j < _res.nsort; j++) { 1867 if (_res.sort_list[j].addr.s_addr == 1868 (sin->sin_addr.s_addr & _res.sort_list[j].mask)) 1869 break; 1870 } 1871 addrs[i].ai = ai; 1872 addrs[i].aval = j; 1873 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1874 needsort = i; 1875 i++; 1876 } 1877 if (!needsort) { 1878 free(addrs); 1879 return 0; 1880 } 1881 1882 while (needsort < naddrs) { 1883 for (j = needsort - 1; j >= 0; j--) { 1884 if (addrs[j].aval > addrs[j+1].aval) { 1885 addr = addrs[j]; 1886 addrs[j] = addrs[j + 1]; 1887 addrs[j + 1] = addr; 1888 } else 1889 break; 1890 } 1891 needsort++; 1892 } 1893 1894 ai = sentinel; 1895 for (i = 0; i < naddrs; ++i) { 1896 ai->ai_next = addrs[i].ai; 1897 ai = ai->ai_next; 1898 } 1899 ai->ai_next = NULL; 1900 free(addrs); 1901 return 0; 1902 } 1903 #endif /*RESOLVSORT*/ 1904 1905 /*ARGSUSED*/ 1906 static int 1907 _dns_getaddrinfo(rv, cb_data, ap) 1908 void *rv; 1909 void *cb_data; 1910 va_list ap; 1911 { 1912 struct addrinfo *ai; 1913 querybuf *buf, *buf2; 1914 const char *hostname; 1915 const struct addrinfo *pai; 1916 struct addrinfo sentinel, *cur; 1917 struct res_target q, q2; 1918 1919 hostname = va_arg(ap, char *); 1920 pai = va_arg(ap, const struct addrinfo *); 1921 1922 memset(&q, 0, sizeof(q2)); 1923 memset(&q2, 0, sizeof(q2)); 1924 memset(&sentinel, 0, sizeof(sentinel)); 1925 cur = &sentinel; 1926 1927 buf = malloc(sizeof(*buf)); 1928 if (!buf) { 1929 h_errno = NETDB_INTERNAL; 1930 return NS_NOTFOUND; 1931 } 1932 buf2 = malloc(sizeof(*buf2)); 1933 if (!buf2) { 1934 free(buf); 1935 h_errno = NETDB_INTERNAL; 1936 return NS_NOTFOUND; 1937 } 1938 1939 switch (pai->ai_family) { 1940 case AF_UNSPEC: 1941 q.name = hostname; 1942 q.qclass = C_IN; 1943 q.qtype = T_A; 1944 q.answer = buf->buf; 1945 q.anslen = sizeof(buf->buf); 1946 q.next = &q2; 1947 q2.name = hostname; 1948 q2.qclass = C_IN; 1949 q2.qtype = T_AAAA; 1950 q2.answer = buf2->buf; 1951 q2.anslen = sizeof(buf2->buf); 1952 break; 1953 case AF_INET: 1954 q.name = hostname; 1955 q.qclass = C_IN; 1956 q.qtype = T_A; 1957 q.answer = buf->buf; 1958 q.anslen = sizeof(buf->buf); 1959 break; 1960 case AF_INET6: 1961 q.name = hostname; 1962 q.qclass = C_IN; 1963 q.qtype = T_AAAA; 1964 q.answer = buf->buf; 1965 q.anslen = sizeof(buf->buf); 1966 break; 1967 default: 1968 free(buf); 1969 free(buf2); 1970 return NS_UNAVAIL; 1971 } 1972 if (res_searchN(hostname, &q) < 0) { 1973 free(buf); 1974 free(buf2); 1975 return NS_NOTFOUND; 1976 } 1977 /* prefer IPv6 */ 1978 if (q.next) { 1979 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai); 1980 if (ai) { 1981 cur->ai_next = ai; 1982 while (cur && cur->ai_next) 1983 cur = cur->ai_next; 1984 } 1985 } 1986 ai = getanswer(buf, q.n, q.name, q.qtype, pai); 1987 if (ai) 1988 cur->ai_next = ai; 1989 free(buf); 1990 free(buf2); 1991 if (sentinel.ai_next == NULL) 1992 switch (h_errno) { 1993 case HOST_NOT_FOUND: 1994 return NS_NOTFOUND; 1995 case TRY_AGAIN: 1996 return NS_TRYAGAIN; 1997 default: 1998 return NS_UNAVAIL; 1999 } 2000 *((struct addrinfo **)rv) = sentinel.ai_next; 2001 return NS_SUCCESS; 2002 } 2003 2004 static void 2005 _sethtent(FILE **hostf) 2006 { 2007 if (!*hostf) 2008 *hostf = fopen(_PATH_HOSTS, "r"); 2009 else 2010 rewind(*hostf); 2011 } 2012 2013 static void 2014 _endhtent(FILE **hostf) 2015 { 2016 if (*hostf) { 2017 (void) fclose(*hostf); 2018 *hostf = NULL; 2019 } 2020 } 2021 2022 static struct addrinfo * 2023 _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2024 { 2025 char *p; 2026 char *cp, *tname, *cname; 2027 struct addrinfo hints, *res0, *res; 2028 int error; 2029 const char *addr; 2030 char hostbuf[8*1024]; 2031 2032 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "r"))) 2033 return (NULL); 2034 again: 2035 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) 2036 return (NULL); 2037 if (*p == '#') 2038 goto again; 2039 cp = strpbrk(p, "#\n"); 2040 if (cp != NULL) 2041 *cp = '\0'; 2042 if (!(cp = strpbrk(p, " \t"))) 2043 goto again; 2044 *cp++ = '\0'; 2045 addr = p; 2046 cname = NULL; 2047 /* if this is not something we're looking for, skip it. */ 2048 while (cp && *cp) { 2049 if (*cp == ' ' || *cp == '\t') { 2050 cp++; 2051 continue; 2052 } 2053 tname = cp; 2054 if (cname == NULL) 2055 cname = cp; 2056 if ((cp = strpbrk(cp, " \t")) != NULL) 2057 *cp++ = '\0'; 2058 if (strcasecmp(name, tname) == 0) 2059 goto found; 2060 } 2061 goto again; 2062 2063 found: 2064 /* we should not glob socktype/protocol here */ 2065 memset(&hints, 0, sizeof(hints)); 2066 hints.ai_family = pai->ai_family; 2067 hints.ai_socktype = SOCK_DGRAM; 2068 hints.ai_protocol = 0; 2069 hints.ai_flags = AI_NUMERICHOST; 2070 error = getaddrinfo(addr, "0", &hints, &res0); 2071 if (error) 2072 goto again; 2073 #ifdef FILTER_V4MAPPED 2074 /* XXX should check all items in the chain */ 2075 if (res0->ai_family == AF_INET6 && 2076 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2077 freeaddrinfo(res0); 2078 goto again; 2079 } 2080 #endif 2081 for (res = res0; res; res = res->ai_next) { 2082 /* cover it up */ 2083 res->ai_flags = pai->ai_flags; 2084 res->ai_socktype = pai->ai_socktype; 2085 res->ai_protocol = pai->ai_protocol; 2086 2087 if (pai->ai_flags & AI_CANONNAME) { 2088 if (get_canonname(pai, res, cname) != 0) { 2089 freeaddrinfo(res0); 2090 goto again; 2091 } 2092 } 2093 } 2094 return res0; 2095 } 2096 2097 /*ARGSUSED*/ 2098 static int 2099 _files_getaddrinfo(rv, cb_data, ap) 2100 void *rv; 2101 void *cb_data; 2102 va_list ap; 2103 { 2104 const char *name; 2105 const struct addrinfo *pai; 2106 struct addrinfo sentinel, *cur; 2107 struct addrinfo *p; 2108 FILE *hostf = NULL; 2109 2110 name = va_arg(ap, char *); 2111 pai = va_arg(ap, struct addrinfo *); 2112 2113 memset(&sentinel, 0, sizeof(sentinel)); 2114 cur = &sentinel; 2115 2116 _sethtent(&hostf); 2117 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2118 cur->ai_next = p; 2119 while (cur && cur->ai_next) 2120 cur = cur->ai_next; 2121 } 2122 _endhtent(&hostf); 2123 2124 *((struct addrinfo **)rv) = sentinel.ai_next; 2125 if (sentinel.ai_next == NULL) 2126 return NS_NOTFOUND; 2127 return NS_SUCCESS; 2128 } 2129 2130 #ifdef YP 2131 /*ARGSUSED*/ 2132 static struct addrinfo * 2133 _yphostent(line, pai) 2134 char *line; 2135 const struct addrinfo *pai; 2136 { 2137 struct addrinfo sentinel, *cur; 2138 struct addrinfo hints, *res, *res0; 2139 int error; 2140 char *p = line; 2141 const char *addr, *canonname; 2142 char *nextline; 2143 char *cp; 2144 2145 addr = canonname = NULL; 2146 2147 memset(&sentinel, 0, sizeof(sentinel)); 2148 cur = &sentinel; 2149 2150 nextline: 2151 /* terminate line */ 2152 cp = strchr(p, '\n'); 2153 if (cp) { 2154 *cp++ = '\0'; 2155 nextline = cp; 2156 } else 2157 nextline = NULL; 2158 2159 cp = strpbrk(p, " \t"); 2160 if (cp == NULL) { 2161 if (canonname == NULL) 2162 return (NULL); 2163 else 2164 goto done; 2165 } 2166 *cp++ = '\0'; 2167 2168 addr = p; 2169 2170 while (cp && *cp) { 2171 if (*cp == ' ' || *cp == '\t') { 2172 cp++; 2173 continue; 2174 } 2175 if (!canonname) 2176 canonname = cp; 2177 if ((cp = strpbrk(cp, " \t")) != NULL) 2178 *cp++ = '\0'; 2179 } 2180 2181 hints = *pai; 2182 hints.ai_flags = AI_NUMERICHOST; 2183 error = getaddrinfo(addr, NULL, &hints, &res0); 2184 if (error == 0) { 2185 for (res = res0; res; res = res->ai_next) { 2186 /* cover it up */ 2187 res->ai_flags = pai->ai_flags; 2188 2189 if (pai->ai_flags & AI_CANONNAME) 2190 (void)get_canonname(pai, res, canonname); 2191 } 2192 } else 2193 res0 = NULL; 2194 if (res0) { 2195 cur->ai_next = res0; 2196 while (cur && cur->ai_next) 2197 cur = cur->ai_next; 2198 } 2199 2200 if (nextline) { 2201 p = nextline; 2202 goto nextline; 2203 } 2204 2205 done: 2206 return sentinel.ai_next; 2207 } 2208 2209 /*ARGSUSED*/ 2210 static int 2211 _yp_getaddrinfo(rv, cb_data, ap) 2212 void *rv; 2213 void *cb_data; 2214 va_list ap; 2215 { 2216 struct addrinfo sentinel, *cur; 2217 struct addrinfo *ai = NULL; 2218 char *ypbuf; 2219 int ypbuflen, r; 2220 const char *name; 2221 const struct addrinfo *pai; 2222 char *ypdomain; 2223 2224 if (_yp_check(&ypdomain) == 0) 2225 return NS_UNAVAIL; 2226 2227 name = va_arg(ap, char *); 2228 pai = va_arg(ap, const struct addrinfo *); 2229 2230 memset(&sentinel, 0, sizeof(sentinel)); 2231 cur = &sentinel; 2232 2233 /* hosts.byname is only for IPv4 (Solaris8) */ 2234 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2235 r = yp_match(ypdomain, "hosts.byname", name, 2236 (int)strlen(name), &ypbuf, &ypbuflen); 2237 if (r == 0) { 2238 struct addrinfo ai4; 2239 2240 ai4 = *pai; 2241 ai4.ai_family = AF_INET; 2242 ai = _yphostent(ypbuf, &ai4); 2243 if (ai) { 2244 cur->ai_next = ai; 2245 while (cur && cur->ai_next) 2246 cur = cur->ai_next; 2247 } 2248 } 2249 free(ypbuf); 2250 } 2251 2252 /* ipnodes.byname can hold both IPv4/v6 */ 2253 r = yp_match(ypdomain, "ipnodes.byname", name, 2254 (int)strlen(name), &ypbuf, &ypbuflen); 2255 if (r == 0) { 2256 ai = _yphostent(ypbuf, pai); 2257 if (ai) 2258 cur->ai_next = ai; 2259 free(ypbuf); 2260 } 2261 2262 if (sentinel.ai_next == NULL) { 2263 h_errno = HOST_NOT_FOUND; 2264 return NS_NOTFOUND; 2265 } 2266 *((struct addrinfo **)rv) = sentinel.ai_next; 2267 return NS_SUCCESS; 2268 } 2269 #endif 2270 2271 /* resolver logic */ 2272 2273 extern const char *_res_hostalias(const char *, char *, size_t); 2274 2275 /* 2276 * Formulate a normal query, send, and await answer. 2277 * Returned answer is placed in supplied buffer "answer". 2278 * Perform preliminary check of answer, returning success only 2279 * if no error is indicated and the answer count is nonzero. 2280 * Return the size of the response on success, -1 on error. 2281 * Error number is left in h_errno. 2282 * 2283 * Caller must parse answer and determine whether it answers the question. 2284 */ 2285 static int 2286 res_queryN(name, target) 2287 const char *name; /* domain name */ 2288 struct res_target *target; 2289 { 2290 u_char *buf; 2291 HEADER *hp; 2292 int n; 2293 struct res_target *t; 2294 int rcode; 2295 int ancount; 2296 2297 rcode = NOERROR; 2298 ancount = 0; 2299 2300 buf = malloc(MAXPACKET); 2301 if (!buf) { 2302 h_errno = NETDB_INTERNAL; 2303 return -1; 2304 } 2305 2306 for (t = target; t; t = t->next) { 2307 int class, type; 2308 u_char *answer; 2309 int anslen; 2310 2311 hp = (HEADER *)(void *)t->answer; 2312 hp->rcode = NOERROR; /* default */ 2313 2314 /* make it easier... */ 2315 class = t->qclass; 2316 type = t->qtype; 2317 answer = t->answer; 2318 anslen = t->anslen; 2319 #ifdef DEBUG 2320 if (_res.options & RES_DEBUG) 2321 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2322 #endif 2323 2324 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, 2325 buf, MAXPACKET); 2326 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) 2327 n = res_opt(n, buf, MAXPACKET, anslen); 2328 if (n <= 0) { 2329 #ifdef DEBUG 2330 if (_res.options & RES_DEBUG) 2331 printf(";; res_query: mkquery failed\n"); 2332 #endif 2333 free(buf); 2334 h_errno = NO_RECOVERY; 2335 return (n); 2336 } 2337 n = res_send(buf, n, answer, anslen); 2338 #if 0 2339 if (n < 0) { 2340 #ifdef DEBUG 2341 if (_res.options & RES_DEBUG) 2342 printf(";; res_query: send error\n"); 2343 #endif 2344 free(buf); 2345 h_errno = TRY_AGAIN; 2346 return (n); 2347 } 2348 #endif 2349 2350 if (n < 0 || n > anslen) 2351 hp->rcode = FORMERR; /* XXX not very informative */ 2352 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2353 rcode = hp->rcode; /* record most recent error */ 2354 #ifdef DEBUG 2355 if (_res.options & RES_DEBUG) 2356 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2357 ntohs(hp->ancount)); 2358 #endif 2359 continue; 2360 } 2361 2362 ancount += ntohs(hp->ancount); 2363 2364 t->n = n; 2365 } 2366 2367 free(buf); 2368 2369 if (ancount == 0) { 2370 switch (rcode) { 2371 case NXDOMAIN: 2372 h_errno = HOST_NOT_FOUND; 2373 break; 2374 case SERVFAIL: 2375 h_errno = TRY_AGAIN; 2376 break; 2377 case NOERROR: 2378 h_errno = NO_DATA; 2379 break; 2380 case FORMERR: 2381 case NOTIMP: 2382 case REFUSED: 2383 default: 2384 h_errno = NO_RECOVERY; 2385 break; 2386 } 2387 return (-1); 2388 } 2389 return (ancount); 2390 } 2391 2392 /* 2393 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2394 * Return the size of the response on success, -1 on error. 2395 * If enabled, implement search rules until answer or unrecoverable failure 2396 * is detected. Error code, if any, is left in h_errno. 2397 */ 2398 static int 2399 res_searchN(name, target) 2400 const char *name; /* domain name */ 2401 struct res_target *target; 2402 { 2403 const char *cp, * const *domain; 2404 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2405 u_int dots; 2406 int trailing_dot, ret, saved_herrno; 2407 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 2408 char abuf[MAXDNAME]; 2409 2410 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2411 h_errno = NETDB_INTERNAL; 2412 return (-1); 2413 } 2414 2415 errno = 0; 2416 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 2417 dots = 0; 2418 for (cp = name; *cp; cp++) 2419 dots += (*cp == '.'); 2420 trailing_dot = 0; 2421 if (cp > name && *--cp == '.') 2422 trailing_dot++; 2423 2424 /* 2425 * if there aren't any dots, it could be a user-level alias 2426 */ 2427 if (!dots && (cp = _res_hostalias(name, abuf, sizeof(abuf))) != NULL) 2428 return (res_queryN(cp, target)); 2429 2430 /* 2431 * If there are dots in the name already, let's just give it a try 2432 * 'as is'. The threshold can be set with the "ndots" option. 2433 */ 2434 saved_herrno = -1; 2435 if (dots >= _res.ndots) { 2436 ret = res_querydomainN(name, NULL, target); 2437 if (ret > 0) 2438 return (ret); 2439 saved_herrno = h_errno; 2440 tried_as_is++; 2441 } 2442 2443 /* 2444 * We do at least one level of search if 2445 * - there is no dot and RES_DEFNAME is set, or 2446 * - there is at least one dot, there is no trailing dot, 2447 * and RES_DNSRCH is set. 2448 */ 2449 if ((!dots && (_res.options & RES_DEFNAMES)) || 2450 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { 2451 int done = 0; 2452 2453 for (domain = (const char * const *)_res.dnsrch; 2454 *domain && !done; 2455 domain++) { 2456 2457 ret = res_querydomainN(name, *domain, target); 2458 if (ret > 0) 2459 return (ret); 2460 2461 /* 2462 * If no server present, give up. 2463 * If name isn't found in this domain, 2464 * keep trying higher domains in the search list 2465 * (if that's enabled). 2466 * On a NO_DATA error, keep trying, otherwise 2467 * a wildcard entry of another type could keep us 2468 * from finding this entry higher in the domain. 2469 * If we get some other error (negative answer or 2470 * server failure), then stop searching up, 2471 * but try the input name below in case it's 2472 * fully-qualified. 2473 */ 2474 if (errno == ECONNREFUSED) { 2475 h_errno = TRY_AGAIN; 2476 return (-1); 2477 } 2478 2479 switch (h_errno) { 2480 case NO_DATA: 2481 got_nodata++; 2482 /* FALLTHROUGH */ 2483 case HOST_NOT_FOUND: 2484 /* keep trying */ 2485 break; 2486 case TRY_AGAIN: 2487 if (hp->rcode == SERVFAIL) { 2488 /* try next search element, if any */ 2489 got_servfail++; 2490 break; 2491 } 2492 /* FALLTHROUGH */ 2493 default: 2494 /* anything else implies that we're done */ 2495 done++; 2496 } 2497 /* 2498 * if we got here for some reason other than DNSRCH, 2499 * we only wanted one iteration of the loop, so stop. 2500 */ 2501 if (!(_res.options & RES_DNSRCH)) 2502 done++; 2503 } 2504 } 2505 2506 /* 2507 * if we have not already tried the name "as is", do that now. 2508 * note that we do this regardless of how many dots were in the 2509 * name or whether it ends with a dot. 2510 */ 2511 if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) { 2512 ret = res_querydomainN(name, NULL, target); 2513 if (ret > 0) 2514 return (ret); 2515 } 2516 2517 /* 2518 * if we got here, we didn't satisfy the search. 2519 * if we did an initial full query, return that query's h_errno 2520 * (note that we wouldn't be here if that query had succeeded). 2521 * else if we ever got a nodata, send that back as the reason. 2522 * else send back meaningless h_errno, that being the one from 2523 * the last DNSRCH we did. 2524 */ 2525 if (saved_herrno != -1) 2526 h_errno = saved_herrno; 2527 else if (got_nodata) 2528 h_errno = NO_DATA; 2529 else if (got_servfail) 2530 h_errno = TRY_AGAIN; 2531 return (-1); 2532 } 2533 2534 /* 2535 * Perform a call on res_query on the concatenation of name and domain, 2536 * removing a trailing dot from name if domain is NULL. 2537 */ 2538 static int 2539 res_querydomainN(name, domain, target) 2540 const char *name, *domain; 2541 struct res_target *target; 2542 { 2543 char nbuf[MAXDNAME]; 2544 const char *longname = nbuf; 2545 size_t n, d; 2546 2547 #ifdef DEBUG 2548 if (_res.options & RES_DEBUG) 2549 printf(";; res_querydomain(%s, %s)\n", 2550 name, domain?domain:"<Nil>"); 2551 #endif 2552 if (domain == NULL) { 2553 /* 2554 * Check for trailing '.'; 2555 * copy without '.' if present. 2556 */ 2557 n = strlen(name); 2558 if (n >= MAXDNAME) { 2559 h_errno = NO_RECOVERY; 2560 return (-1); 2561 } 2562 if (n > 0 && name[--n] == '.') { 2563 strncpy(nbuf, name, n); 2564 nbuf[n] = '\0'; 2565 } else 2566 longname = name; 2567 } else { 2568 n = strlen(name); 2569 d = strlen(domain); 2570 if (n + d + 1 >= MAXDNAME) { 2571 h_errno = NO_RECOVERY; 2572 return (-1); 2573 } 2574 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2575 } 2576 return (res_queryN(longname, target)); 2577 } 2578