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. 42 * current code - SEGV on freeaddrinfo(NULL) 43 * Note: 44 * - We use getipnodebyname() just for thread-safeness. There's no intent 45 * to let it do PF_UNSPEC (actually we never pass PF_UNSPEC to 46 * getipnodebyname(). 47 * - The code filters out AFs that are not supported by the kernel, 48 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 49 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 50 * in ai_flags? 51 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 52 * (1) what should we do against numeric hostname (2) what should we do 53 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 54 * non-loopback address configured? global address configured? 55 * - To avoid search order issue, we have a big amount of code duplicate 56 * from gethnamaddr.c and some other places. The issues that there's no 57 * lower layer function to lookup "IPv4 or IPv6" record. Calling 58 * gethostbyname2 from getaddrinfo will end up in wrong search order, as 59 * follows: 60 * - The code makes use of following calls when asked to resolver with 61 * ai_family = PF_UNSPEC: 62 * getipnodebyname(host, AF_INET6); 63 * getipnodebyname(host, AF_INET); 64 * This will result in the following queries if the node is configure to 65 * prefer /etc/hosts than DNS: 66 * lookup /etc/hosts for IPv6 address 67 * lookup DNS for IPv6 address 68 * lookup /etc/hosts for IPv4 address 69 * lookup DNS for IPv4 address 70 * which may not meet people's requirement. 71 * The right thing to happen is to have underlying layer which does 72 * PF_UNSPEC lookup (lookup both) and return chain of addrinfos. 73 * This would result in a bit of code duplicate with _dns_ghbyname() and 74 * friends. 75 */ 76 /* 77 * diffs with other KAME platforms: 78 * - other KAME platforms already nuked FAITH ($GAI), but as FreeBSD 79 * 4.0-RELEASE supplies it, we still have the code here. 80 * - AI_ADDRCONFIG support is supplied 81 * - some of FreeBSD style (#define tabify and others) 82 * - classful IPv4 numeric (127.1) is allowed. 83 */ 84 85 #include <sys/cdefs.h> 86 __FBSDID("$FreeBSD$"); 87 88 #include "namespace.h" 89 #include <sys/types.h> 90 #include <sys/param.h> 91 #include <sys/socket.h> 92 #include <net/if.h> 93 #include <netinet/in.h> 94 #include <arpa/inet.h> 95 #include <arpa/nameser.h> 96 #include <rpc/rpc.h> 97 #include <rpcsvc/yp_prot.h> 98 #include <rpcsvc/ypclnt.h> 99 #include <netdb.h> 100 #include <resolv.h> 101 #include <string.h> 102 #include <stdlib.h> 103 #include <stddef.h> 104 #include <ctype.h> 105 #include <unistd.h> 106 #include <stdio.h> 107 #include <errno.h> 108 #ifdef DEBUG 109 #include <syslog.h> 110 #endif 111 112 #include <syslog.h> 113 #include <stdarg.h> 114 #include <nsswitch.h> 115 #include "un-namespace.h" 116 117 #if defined(__KAME__) && defined(INET6) 118 # define FAITH 119 #endif 120 121 #define SUCCESS 0 122 #define ANY 0 123 #define YES 1 124 #define NO 0 125 126 static const char in_addrany[] = { 0, 0, 0, 0 }; 127 static const char in6_addrany[] = { 128 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 129 }; 130 static const char in_loopback[] = { 127, 0, 0, 1 }; 131 static const char in6_loopback[] = { 132 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 133 }; 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 static const ns_src default_dns_files[] = { 197 { NSSRC_FILES, NS_SUCCESS }, 198 { NSSRC_DNS, NS_SUCCESS }, 199 { 0 } 200 }; 201 202 #if PACKETSZ > 1024 203 #define MAXPACKET PACKETSZ 204 #else 205 #define MAXPACKET 1024 206 #endif 207 208 typedef union { 209 HEADER hdr; 210 u_char buf[MAXPACKET]; 211 } querybuf; 212 213 struct res_target { 214 struct res_target *next; 215 const char *name; /* domain name */ 216 int qclass, qtype; /* class and type of query */ 217 u_char *answer; /* buffer to put answer */ 218 int anslen; /* size of answer buffer */ 219 int n; /* result length */ 220 }; 221 222 static int str_isnumber(const char *); 223 static int explore_fqdn(const struct addrinfo *, const char *, 224 const char *, struct addrinfo **); 225 static int explore_null(const struct addrinfo *, 226 const char *, struct addrinfo **); 227 static int explore_numeric(const struct addrinfo *, const char *, 228 const char *, struct addrinfo **); 229 static int explore_numeric_scope(const struct addrinfo *, const char *, 230 const char *, struct addrinfo **); 231 static int get_canonname(const struct addrinfo *, 232 struct addrinfo *, const char *); 233 static struct addrinfo *get_ai(const struct addrinfo *, 234 const struct afd *, const char *); 235 static int get_portmatch(const struct addrinfo *, const char *); 236 static int get_port(struct addrinfo *, const char *, int); 237 static const struct afd *find_afd(int); 238 static int addrconfig(struct addrinfo *); 239 #ifdef INET6 240 static int ip6_str2scopeid(char *, struct sockaddr_in6 *); 241 #endif 242 243 static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 244 const struct addrinfo *); 245 static int _dns_getaddrinfo(void *, void *, va_list); 246 static void _sethtent(void); 247 static void _endhtent(void); 248 static struct addrinfo *_gethtent(const char *, const struct addrinfo *); 249 static int _files_getaddrinfo(void *, void *, va_list); 250 #ifdef YP 251 static struct addrinfo *_yphostent(char *, const struct addrinfo *); 252 static int _yp_getaddrinfo(void *, void *, va_list); 253 extern int _yp_check(char **); 254 #endif 255 256 static int res_queryN(const char *, struct res_target *); 257 static int res_searchN(const char *, struct res_target *); 258 static int res_querydomainN(const char *, const char *, 259 struct res_target *); 260 261 static char *ai_errlist[] = { 262 "Success", 263 "Address family for hostname not supported", /* EAI_ADDRFAMILY */ 264 "Temporary failure in name resolution", /* EAI_AGAIN */ 265 "Invalid value for ai_flags", /* EAI_BADFLAGS */ 266 "Non-recoverable failure in name resolution", /* EAI_FAIL */ 267 "ai_family not supported", /* EAI_FAMILY */ 268 "Memory allocation failure", /* EAI_MEMORY */ 269 "No address associated with hostname", /* EAI_NODATA */ 270 "hostname nor servname provided, or not known", /* EAI_NONAME */ 271 "servname not supported for ai_socktype", /* EAI_SERVICE */ 272 "ai_socktype not supported", /* EAI_SOCKTYPE */ 273 "System error returned in errno", /* EAI_SYSTEM */ 274 "Invalid value for hints", /* EAI_BADHINTS */ 275 "Resolved protocol is unknown", /* EAI_PROTOCOL */ 276 "Unknown error", /* EAI_MAX */ 277 }; 278 279 /* XXX macros that make external reference is BAD. */ 280 281 #define GET_AI(ai, afd, addr) \ 282 do { \ 283 /* external reference: pai, error, and label free */ \ 284 (ai) = get_ai(pai, (afd), (addr)); \ 285 if ((ai) == NULL) { \ 286 error = EAI_MEMORY; \ 287 goto free; \ 288 } \ 289 } while (/*CONSTCOND*/0) 290 291 #define GET_PORT(ai, serv) \ 292 do { \ 293 /* external reference: error and label free */ \ 294 error = get_port((ai), (serv), 0); \ 295 if (error != 0) \ 296 goto free; \ 297 } while (/*CONSTCOND*/0) 298 299 #define GET_CANONNAME(ai, str) \ 300 do { \ 301 /* external reference: pai, error and label free */ \ 302 error = get_canonname(pai, (ai), (str)); \ 303 if (error != 0) \ 304 goto free; \ 305 } while (/*CONSTCOND*/0) 306 307 #define ERR(err) \ 308 do { \ 309 /* external reference: error, and label bad */ \ 310 error = (err); \ 311 goto bad; \ 312 /*NOTREACHED*/ \ 313 } while (/*CONSTCOND*/0) 314 315 #define MATCH_FAMILY(x, y, w) \ 316 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 317 #define MATCH(x, y, w) \ 318 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 319 320 char * 321 gai_strerror(ecode) 322 int ecode; 323 { 324 if (ecode < 0 || ecode > EAI_MAX) 325 ecode = EAI_MAX; 326 return ai_errlist[ecode]; 327 } 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 str_isnumber(p) 347 const char *p; 348 { 349 char *ep; 350 351 if (*p == '\0') 352 return NO; 353 ep = NULL; 354 (void)strtoul(p, &ep, 10); 355 if (ep && *ep == '\0') 356 return YES; 357 else 358 return NO; 359 } 360 361 int 362 getaddrinfo(hostname, servname, hints, res) 363 const char *hostname, *servname; 364 const struct addrinfo *hints; 365 struct addrinfo **res; 366 { 367 struct addrinfo sentinel; 368 struct addrinfo *cur; 369 int error = 0; 370 struct addrinfo ai; 371 struct addrinfo ai0; 372 struct addrinfo *pai; 373 const struct explore *ex; 374 375 memset(&sentinel, 0, sizeof(sentinel)); 376 cur = &sentinel; 377 pai = &ai; 378 pai->ai_flags = 0; 379 pai->ai_family = PF_UNSPEC; 380 pai->ai_socktype = ANY; 381 pai->ai_protocol = ANY; 382 pai->ai_addrlen = 0; 383 pai->ai_canonname = NULL; 384 pai->ai_addr = NULL; 385 pai->ai_next = NULL; 386 387 if (hostname == NULL && servname == NULL) 388 return EAI_NONAME; 389 if (hints) { 390 /* error check for hints */ 391 if (hints->ai_addrlen || hints->ai_canonname || 392 hints->ai_addr || hints->ai_next) 393 ERR(EAI_BADHINTS); /* xxx */ 394 if (hints->ai_flags & ~AI_MASK) 395 ERR(EAI_BADFLAGS); 396 switch (hints->ai_family) { 397 case PF_UNSPEC: 398 case PF_INET: 399 #ifdef INET6 400 case PF_INET6: 401 #endif 402 break; 403 default: 404 ERR(EAI_FAMILY); 405 } 406 memcpy(pai, hints, sizeof(*pai)); 407 408 /* 409 * if both socktype/protocol are specified, check if they 410 * are meaningful combination. 411 */ 412 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 413 for (ex = explore; ex->e_af >= 0; ex++) { 414 if (pai->ai_family != ex->e_af) 415 continue; 416 if (ex->e_socktype == ANY) 417 continue; 418 if (ex->e_protocol == ANY) 419 continue; 420 if (pai->ai_socktype == ex->e_socktype 421 && pai->ai_protocol != ex->e_protocol) { 422 ERR(EAI_BADHINTS); 423 } 424 } 425 } 426 } 427 428 /* 429 * post-2553: AI_ALL and AI_V4MAPPED are effective only against 430 * AF_INET6 query. They needs to be ignored if specified in other 431 * occassions. 432 */ 433 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 434 case AI_V4MAPPED: 435 case AI_ALL | AI_V4MAPPED: 436 if (pai->ai_family != AF_INET6) 437 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 438 break; 439 case AI_ALL: 440 #if 1 441 /* illegal */ 442 ERR(EAI_BADFLAGS); 443 #else 444 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 445 #endif 446 break; 447 } 448 449 /* 450 * check for special cases. (1) numeric servname is disallowed if 451 * socktype/protocol are left unspecified. (2) servname is disallowed 452 * for raw and other inet{,6} sockets. 453 */ 454 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 455 #ifdef PF_INET6 456 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 457 #endif 458 ) { 459 ai0 = *pai; /* backup *pai */ 460 461 if (pai->ai_family == PF_UNSPEC) { 462 #ifdef PF_INET6 463 pai->ai_family = PF_INET6; 464 #else 465 pai->ai_family = PF_INET; 466 #endif 467 } 468 error = get_portmatch(pai, servname); 469 if (error) 470 ERR(error); 471 472 *pai = ai0; 473 } 474 475 ai0 = *pai; 476 477 /* NULL hostname, or numeric hostname */ 478 for (ex = explore; ex->e_af >= 0; ex++) { 479 *pai = ai0; 480 481 /* PF_UNSPEC entries are prepared for DNS queries only */ 482 if (ex->e_af == PF_UNSPEC) 483 continue; 484 485 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 486 continue; 487 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 488 continue; 489 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 490 continue; 491 492 if (pai->ai_family == PF_UNSPEC) 493 pai->ai_family = ex->e_af; 494 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 495 pai->ai_socktype = ex->e_socktype; 496 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 497 pai->ai_protocol = ex->e_protocol; 498 499 if (hostname == NULL) 500 error = explore_null(pai, servname, &cur->ai_next); 501 else 502 error = explore_numeric_scope(pai, hostname, servname, &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 goto good; 518 519 if (pai->ai_flags & AI_NUMERICHOST) 520 ERR(EAI_NONAME); 521 if (hostname == NULL) 522 ERR(EAI_NODATA); 523 524 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 525 ERR(EAI_FAIL); 526 527 /* 528 * hostname as alphabetical name. 529 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 530 * outer loop by AFs. 531 */ 532 for (ex = explore; ex->e_af >= 0; ex++) { 533 *pai = ai0; 534 535 /* require exact match for family field */ 536 if (pai->ai_family != ex->e_af) 537 continue; 538 539 if (!MATCH(pai->ai_socktype, ex->e_socktype, 540 WILD_SOCKTYPE(ex))) { 541 continue; 542 } 543 if (!MATCH(pai->ai_protocol, ex->e_protocol, 544 WILD_PROTOCOL(ex))) { 545 continue; 546 } 547 548 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 549 pai->ai_socktype = ex->e_socktype; 550 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 551 pai->ai_protocol = ex->e_protocol; 552 553 error = explore_fqdn(pai, hostname, servname, 554 &cur->ai_next); 555 556 while (cur && cur->ai_next) 557 cur = cur->ai_next; 558 } 559 560 /* XXX */ 561 if (sentinel.ai_next) 562 error = 0; 563 564 if (error) 565 goto free; 566 if (error == 0) { 567 if (sentinel.ai_next) { 568 good: 569 *res = sentinel.ai_next; 570 return SUCCESS; 571 } else 572 error = EAI_FAIL; 573 } 574 free: 575 bad: 576 if (sentinel.ai_next) 577 freeaddrinfo(sentinel.ai_next); 578 *res = NULL; 579 return error; 580 } 581 582 /* 583 * FQDN hostname, DNS lookup 584 */ 585 static int 586 explore_fqdn(pai, hostname, servname, res) 587 const struct addrinfo *pai; 588 const char *hostname; 589 const char *servname; 590 struct addrinfo **res; 591 { 592 struct addrinfo *result; 593 struct addrinfo *cur; 594 int error = 0; 595 static const ns_dtab dtab[] = { 596 NS_FILES_CB(_files_getaddrinfo, NULL) 597 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 598 NS_NIS_CB(_yp_getaddrinfo, NULL) 599 { 0 } 600 }; 601 602 result = NULL; 603 604 /* 605 * if the servname does not match socktype/protocol, ignore it. 606 */ 607 if (get_portmatch(pai, servname) != 0) 608 return 0; 609 610 switch (nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 611 default_dns_files, hostname, pai)) { 612 case NS_TRYAGAIN: 613 error = EAI_AGAIN; 614 goto free; 615 case NS_UNAVAIL: 616 error = EAI_FAIL; 617 goto free; 618 case NS_NOTFOUND: 619 error = EAI_NODATA; 620 goto free; 621 case NS_SUCCESS: 622 error = 0; 623 for (cur = result; cur; cur = cur->ai_next) { 624 GET_PORT(cur, servname); 625 /* canonname should be filled already */ 626 } 627 break; 628 } 629 630 *res = result; 631 632 return 0; 633 634 free: 635 if (result) 636 freeaddrinfo(result); 637 return error; 638 } 639 640 /* 641 * hostname == NULL. 642 * passive socket -> anyaddr (0.0.0.0 or ::) 643 * non-passive socket -> localhost (127.0.0.1 or ::1) 644 */ 645 static int 646 explore_null(pai, servname, res) 647 const struct addrinfo *pai; 648 const char *servname; 649 struct addrinfo **res; 650 { 651 int s; 652 const struct afd *afd; 653 struct addrinfo *cur; 654 struct addrinfo sentinel; 655 int error; 656 657 *res = NULL; 658 sentinel.ai_next = NULL; 659 cur = &sentinel; 660 661 /* 662 * filter out AFs that are not supported by the kernel 663 * XXX errno? 664 */ 665 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 666 if (s < 0) { 667 if (errno != EMFILE) 668 return 0; 669 } else 670 _close(s); 671 672 /* 673 * if the servname does not match socktype/protocol, ignore it. 674 */ 675 if (get_portmatch(pai, servname) != 0) 676 return 0; 677 678 afd = find_afd(pai->ai_family); 679 if (afd == NULL) 680 return 0; 681 682 if (pai->ai_flags & AI_PASSIVE) { 683 GET_AI(cur->ai_next, afd, afd->a_addrany); 684 /* xxx meaningless? 685 * GET_CANONNAME(cur->ai_next, "anyaddr"); 686 */ 687 GET_PORT(cur->ai_next, servname); 688 } else { 689 GET_AI(cur->ai_next, afd, afd->a_loopback); 690 /* xxx meaningless? 691 * GET_CANONNAME(cur->ai_next, "localhost"); 692 */ 693 GET_PORT(cur->ai_next, servname); 694 } 695 cur = cur->ai_next; 696 697 *res = sentinel.ai_next; 698 return 0; 699 700 free: 701 if (sentinel.ai_next) 702 freeaddrinfo(sentinel.ai_next); 703 return error; 704 } 705 706 /* 707 * numeric hostname 708 */ 709 static int 710 explore_numeric(pai, hostname, servname, res) 711 const struct addrinfo *pai; 712 const char *hostname; 713 const char *servname; 714 struct addrinfo **res; 715 { 716 const struct afd *afd; 717 struct addrinfo *cur; 718 struct addrinfo sentinel; 719 int error; 720 char pton[PTON_MAX]; 721 722 *res = NULL; 723 sentinel.ai_next = NULL; 724 cur = &sentinel; 725 726 /* 727 * if the servname does not match socktype/protocol, ignore it. 728 */ 729 if (get_portmatch(pai, servname) != 0) 730 return 0; 731 732 afd = find_afd(pai->ai_family); 733 if (afd == NULL) 734 return 0; 735 736 switch (afd->a_af) { 737 #if 1 /*X/Open spec*/ 738 case AF_INET: 739 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 740 if (pai->ai_family == afd->a_af || 741 pai->ai_family == PF_UNSPEC /*?*/) { 742 GET_AI(cur->ai_next, afd, pton); 743 GET_PORT(cur->ai_next, servname); 744 while (cur && cur->ai_next) 745 cur = cur->ai_next; 746 } else 747 ERR(EAI_FAMILY); /*xxx*/ 748 } 749 break; 750 #endif 751 default: 752 if (inet_pton(afd->a_af, hostname, pton) == 1) { 753 if (pai->ai_family == afd->a_af || 754 pai->ai_family == PF_UNSPEC /*?*/) { 755 GET_AI(cur->ai_next, afd, pton); 756 GET_PORT(cur->ai_next, servname); 757 while (cur && cur->ai_next) 758 cur = cur->ai_next; 759 } else 760 ERR(EAI_FAMILY); /*xxx*/ 761 } 762 break; 763 } 764 765 *res = sentinel.ai_next; 766 return 0; 767 768 free: 769 bad: 770 if (sentinel.ai_next) 771 freeaddrinfo(sentinel.ai_next); 772 return error; 773 } 774 775 /* 776 * numeric hostname with scope 777 */ 778 static int 779 explore_numeric_scope(pai, hostname, servname, res) 780 const struct addrinfo *pai; 781 const char *hostname; 782 const char *servname; 783 struct addrinfo **res; 784 { 785 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 786 return explore_numeric(pai, hostname, servname, res); 787 #else 788 const struct afd *afd; 789 struct addrinfo *cur; 790 int error; 791 char *cp, *hostname2 = NULL, *scope, *addr; 792 struct sockaddr_in6 *sin6; 793 794 /* 795 * if the servname does not match socktype/protocol, ignore it. 796 */ 797 if (get_portmatch(pai, servname) != 0) 798 return 0; 799 800 afd = find_afd(pai->ai_family); 801 if (afd == NULL) 802 return 0; 803 804 if (!afd->a_scoped) 805 return explore_numeric(pai, hostname, servname, res); 806 807 cp = strchr(hostname, SCOPE_DELIMITER); 808 if (cp == NULL) 809 return explore_numeric(pai, hostname, servname, res); 810 811 /* 812 * Handle special case of <scoped_address><delimiter><scope id> 813 */ 814 hostname2 = strdup(hostname); 815 if (hostname2 == NULL) 816 return EAI_MEMORY; 817 /* terminate at the delimiter */ 818 hostname2[cp - hostname] = '\0'; 819 addr = hostname2; 820 scope = cp + 1; 821 822 error = explore_numeric(pai, addr, servname, res); 823 if (error == 0) { 824 int scopeid; 825 826 for (cur = *res; cur; cur = cur->ai_next) { 827 if (cur->ai_family != AF_INET6) 828 continue; 829 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 830 if ((scopeid = ip6_str2scopeid(scope, sin6)) == -1) { 831 free(hostname2); 832 return(EAI_NODATA); /* XXX: is return OK? */ 833 } 834 sin6->sin6_scope_id = scopeid; 835 } 836 } 837 838 free(hostname2); 839 840 return error; 841 #endif 842 } 843 844 static int 845 get_canonname(pai, ai, str) 846 const struct addrinfo *pai; 847 struct addrinfo *ai; 848 const char *str; 849 { 850 if ((pai->ai_flags & AI_CANONNAME) != 0) { 851 ai->ai_canonname = (char *)malloc(strlen(str) + 1); 852 if (ai->ai_canonname == NULL) 853 return EAI_MEMORY; 854 strcpy(ai->ai_canonname, str); 855 } 856 return 0; 857 } 858 859 static struct addrinfo * 860 get_ai(pai, afd, addr) 861 const struct addrinfo *pai; 862 const struct afd *afd; 863 const char *addr; 864 { 865 char *p; 866 struct addrinfo *ai; 867 #ifdef FAITH 868 struct in6_addr faith_prefix; 869 char *fp_str; 870 int translate = 0; 871 #endif 872 873 #ifdef FAITH 874 /* 875 * Transfrom an IPv4 addr into a special IPv6 addr format for 876 * IPv6->IPv4 translation gateway. (only TCP is supported now) 877 * 878 * +-----------------------------------+------------+ 879 * | faith prefix part (12 bytes) | embedded | 880 * | | IPv4 addr part (4 bytes) 881 * +-----------------------------------+------------+ 882 * 883 * faith prefix part is specified as ascii IPv6 addr format 884 * in environmental variable GAI. 885 * For FAITH to work correctly, routing to faith prefix must be 886 * setup toward a machine where a FAITH daemon operates. 887 * Also, the machine must enable some mechanizm 888 * (e.g. faith interface hack) to divert those packet with 889 * faith prefixed destination addr to user-land FAITH daemon. 890 */ 891 fp_str = getenv("GAI"); 892 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 893 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 894 u_int32_t v4a; 895 u_int8_t v4a_top; 896 897 memcpy(&v4a, addr, sizeof v4a); 898 v4a_top = v4a >> IN_CLASSA_NSHIFT; 899 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 900 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 901 afd = &afdl[N_INET6]; 902 memcpy(&faith_prefix.s6_addr[12], addr, 903 sizeof(struct in_addr)); 904 translate = 1; 905 } 906 } 907 #endif 908 909 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 910 + (afd->a_socklen)); 911 if (ai == NULL) 912 return NULL; 913 914 memcpy(ai, pai, sizeof(struct addrinfo)); 915 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 916 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 917 ai->ai_addr->sa_len = afd->a_socklen; 918 ai->ai_addrlen = afd->a_socklen; 919 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 920 p = (char *)(void *)(ai->ai_addr); 921 #ifdef FAITH 922 if (translate == 1) 923 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 924 else 925 #endif 926 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 927 return ai; 928 } 929 930 static int 931 get_portmatch(ai, servname) 932 const struct addrinfo *ai; 933 const char *servname; 934 { 935 936 /* get_port does not touch first argument. when matchonly == 1. */ 937 /* LINTED const cast */ 938 return get_port((struct addrinfo *)ai, servname, 1); 939 } 940 941 static int 942 get_port(ai, servname, matchonly) 943 struct addrinfo *ai; 944 const char *servname; 945 int matchonly; 946 { 947 const char *proto; 948 struct servent *sp; 949 int port; 950 int allownumeric; 951 952 if (servname == NULL) 953 return 0; 954 switch (ai->ai_family) { 955 case AF_INET: 956 #ifdef AF_INET6 957 case AF_INET6: 958 #endif 959 break; 960 default: 961 return 0; 962 } 963 964 switch (ai->ai_socktype) { 965 case SOCK_RAW: 966 return EAI_SERVICE; 967 case SOCK_DGRAM: 968 case SOCK_STREAM: 969 allownumeric = 1; 970 break; 971 case ANY: 972 allownumeric = 0; 973 break; 974 default: 975 return EAI_SOCKTYPE; 976 } 977 978 if (str_isnumber(servname)) { 979 if (!allownumeric) 980 return EAI_SERVICE; 981 port = htons(atoi(servname)); 982 if (port < 0 || port > 65535) 983 return EAI_SERVICE; 984 } else { 985 switch (ai->ai_socktype) { 986 case SOCK_DGRAM: 987 proto = "udp"; 988 break; 989 case SOCK_STREAM: 990 proto = "tcp"; 991 break; 992 default: 993 proto = NULL; 994 break; 995 } 996 997 if ((sp = getservbyname(servname, proto)) == NULL) 998 return EAI_SERVICE; 999 port = sp->s_port; 1000 } 1001 1002 if (!matchonly) { 1003 switch (ai->ai_family) { 1004 case AF_INET: 1005 ((struct sockaddr_in *)(void *) 1006 ai->ai_addr)->sin_port = port; 1007 break; 1008 #ifdef INET6 1009 case AF_INET6: 1010 ((struct sockaddr_in6 *)(void *) 1011 ai->ai_addr)->sin6_port = port; 1012 break; 1013 #endif 1014 } 1015 } 1016 1017 return 0; 1018 } 1019 1020 static const struct afd * 1021 find_afd(af) 1022 int af; 1023 { 1024 const struct afd *afd; 1025 1026 if (af == PF_UNSPEC) 1027 return NULL; 1028 for (afd = afdl; afd->a_af; afd++) { 1029 if (afd->a_af == af) 1030 return afd; 1031 } 1032 return NULL; 1033 } 1034 1035 /* 1036 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1037 * will take care of it. 1038 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1039 * if the code is right or not. 1040 * 1041 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1042 * _dns_getaddrinfo. 1043 */ 1044 static int 1045 addrconfig(pai) 1046 struct addrinfo *pai; 1047 { 1048 int s, af; 1049 1050 /* 1051 * TODO: 1052 * Note that implementation dependent test for address 1053 * configuration should be done everytime called 1054 * (or apropriate interval), 1055 * because addresses will be dynamically assigned or deleted. 1056 */ 1057 af = pai->ai_family; 1058 if (af == AF_UNSPEC) { 1059 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1060 af = AF_INET; 1061 else { 1062 _close(s); 1063 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1064 af = AF_INET6; 1065 else 1066 _close(s); 1067 } 1068 } 1069 if (af != AF_UNSPEC) { 1070 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1071 return 0; 1072 _close(s); 1073 } 1074 pai->ai_family = af; 1075 return 1; 1076 } 1077 1078 #ifdef INET6 1079 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1080 static int 1081 ip6_str2scopeid(scope, sin6) 1082 char *scope; 1083 struct sockaddr_in6 *sin6; 1084 { 1085 int scopeid; 1086 struct in6_addr *a6 = &sin6->sin6_addr; 1087 char *ep; 1088 1089 /* empty scopeid portion is invalid */ 1090 if (*scope == '\0') 1091 return -1; 1092 1093 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1094 /* 1095 * We currently assume a one-to-one mapping between links 1096 * and interfaces, so we simply use interface indices for 1097 * like-local scopes. 1098 */ 1099 scopeid = if_nametoindex(scope); 1100 if (scopeid == 0) 1101 goto trynumeric; 1102 return(scopeid); 1103 } 1104 1105 /* still unclear about literal, allow numeric only - placeholder */ 1106 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1107 goto trynumeric; 1108 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1109 goto trynumeric; 1110 else 1111 goto trynumeric; /* global */ 1112 1113 /* try to convert to a numeric id as a last resort */ 1114 trynumeric: 1115 scopeid = (int)strtoul(scope, &ep, 10); 1116 if (*ep == '\0') 1117 return scopeid; 1118 else 1119 return -1; 1120 } 1121 #endif 1122 1123 #ifdef DEBUG 1124 static const char AskedForGot[] = 1125 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1126 #endif 1127 static FILE *hostf = NULL; 1128 1129 static struct addrinfo * 1130 getanswer(answer, anslen, qname, qtype, pai) 1131 const querybuf *answer; 1132 int anslen; 1133 const char *qname; 1134 int qtype; 1135 const struct addrinfo *pai; 1136 { 1137 struct addrinfo sentinel, *cur; 1138 struct addrinfo ai; 1139 const struct afd *afd; 1140 char *canonname; 1141 const HEADER *hp; 1142 const u_char *cp; 1143 int n; 1144 const u_char *eom; 1145 char *bp; 1146 int type, class, buflen, ancount, qdcount; 1147 int haveanswer, had_error; 1148 char tbuf[MAXDNAME]; 1149 int (*name_ok)(const char *); 1150 char hostbuf[8*1024]; 1151 1152 memset(&sentinel, 0, sizeof(sentinel)); 1153 cur = &sentinel; 1154 1155 canonname = NULL; 1156 eom = answer->buf + anslen; 1157 switch (qtype) { 1158 case T_A: 1159 case T_AAAA: 1160 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1161 name_ok = res_hnok; 1162 break; 1163 default: 1164 return (NULL); /* XXX should be abort(); */ 1165 } 1166 /* 1167 * find first satisfactory answer 1168 */ 1169 hp = &answer->hdr; 1170 ancount = ntohs(hp->ancount); 1171 qdcount = ntohs(hp->qdcount); 1172 bp = hostbuf; 1173 buflen = sizeof hostbuf; 1174 cp = answer->buf + HFIXEDSZ; 1175 if (qdcount != 1) { 1176 h_errno = NO_RECOVERY; 1177 return (NULL); 1178 } 1179 n = dn_expand(answer->buf, eom, cp, bp, buflen); 1180 if ((n < 0) || !(*name_ok)(bp)) { 1181 h_errno = NO_RECOVERY; 1182 return (NULL); 1183 } 1184 cp += n + QFIXEDSZ; 1185 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1186 /* res_send() has already verified that the query name is the 1187 * same as the one we sent; this just gets the expanded name 1188 * (i.e., with the succeeding search-domain tacked on). 1189 */ 1190 n = strlen(bp) + 1; /* for the \0 */ 1191 if (n >= MAXHOSTNAMELEN) { 1192 h_errno = NO_RECOVERY; 1193 return (NULL); 1194 } 1195 canonname = bp; 1196 bp += n; 1197 buflen -= n; 1198 /* The qname can be abbreviated, but h_name is now absolute. */ 1199 qname = canonname; 1200 } 1201 haveanswer = 0; 1202 had_error = 0; 1203 while (ancount-- > 0 && cp < eom && !had_error) { 1204 n = dn_expand(answer->buf, eom, cp, bp, buflen); 1205 if ((n < 0) || !(*name_ok)(bp)) { 1206 had_error++; 1207 continue; 1208 } 1209 cp += n; /* name */ 1210 type = _getshort(cp); 1211 cp += INT16SZ; /* type */ 1212 class = _getshort(cp); 1213 cp += INT16SZ + INT32SZ; /* class, TTL */ 1214 n = _getshort(cp); 1215 cp += INT16SZ; /* len */ 1216 if (class != C_IN) { 1217 /* XXX - debug? syslog? */ 1218 cp += n; 1219 continue; /* XXX - had_error++ ? */ 1220 } 1221 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1222 type == T_CNAME) { 1223 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1224 if ((n < 0) || !(*name_ok)(tbuf)) { 1225 had_error++; 1226 continue; 1227 } 1228 cp += n; 1229 /* Get canonical name. */ 1230 n = strlen(tbuf) + 1; /* for the \0 */ 1231 if (n > buflen || n >= MAXHOSTNAMELEN) { 1232 had_error++; 1233 continue; 1234 } 1235 strcpy(bp, tbuf); 1236 canonname = bp; 1237 bp += n; 1238 buflen -= n; 1239 continue; 1240 } 1241 if (qtype == T_ANY) { 1242 if (!(type == T_A || type == T_AAAA)) { 1243 cp += n; 1244 continue; 1245 } 1246 } else if (type != qtype) { 1247 #ifdef DEBUG 1248 if (type != T_KEY && type != T_SIG) 1249 syslog(LOG_NOTICE|LOG_AUTH, 1250 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1251 qname, p_class(C_IN), p_type(qtype), 1252 p_type(type)); 1253 #endif 1254 cp += n; 1255 continue; /* XXX - had_error++ ? */ 1256 } 1257 switch (type) { 1258 case T_A: 1259 case T_AAAA: 1260 if (strcasecmp(canonname, bp) != 0) { 1261 #ifdef DEBUG 1262 syslog(LOG_NOTICE|LOG_AUTH, 1263 AskedForGot, canonname, bp); 1264 #endif 1265 cp += n; 1266 continue; /* XXX - had_error++ ? */ 1267 } 1268 if (type == T_A && n != INADDRSZ) { 1269 cp += n; 1270 continue; 1271 } 1272 if (type == T_AAAA && n != IN6ADDRSZ) { 1273 cp += n; 1274 continue; 1275 } 1276 #ifdef FILTER_V4MAPPED 1277 if (type == T_AAAA) { 1278 struct in6_addr in6; 1279 memcpy(&in6, cp, sizeof(in6)); 1280 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1281 cp += n; 1282 continue; 1283 } 1284 } 1285 #endif 1286 if (!haveanswer) { 1287 int nn; 1288 1289 canonname = bp; 1290 nn = strlen(bp) + 1; /* for the \0 */ 1291 bp += nn; 1292 buflen -= nn; 1293 } 1294 1295 /* don't overwrite pai */ 1296 ai = *pai; 1297 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1298 afd = find_afd(ai.ai_family); 1299 if (afd == NULL) { 1300 cp += n; 1301 continue; 1302 } 1303 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1304 if (cur->ai_next == NULL) 1305 had_error++; 1306 while (cur && cur->ai_next) 1307 cur = cur->ai_next; 1308 cp += n; 1309 break; 1310 default: 1311 abort(); 1312 } 1313 if (!had_error) 1314 haveanswer++; 1315 } 1316 if (haveanswer) { 1317 if (!canonname) 1318 (void)get_canonname(pai, sentinel.ai_next, qname); 1319 else 1320 (void)get_canonname(pai, sentinel.ai_next, canonname); 1321 h_errno = NETDB_SUCCESS; 1322 return sentinel.ai_next; 1323 } 1324 1325 h_errno = NO_RECOVERY; 1326 return NULL; 1327 } 1328 1329 /*ARGSUSED*/ 1330 static int 1331 _dns_getaddrinfo(rv, cb_data, ap) 1332 void *rv; 1333 void *cb_data; 1334 va_list ap; 1335 { 1336 struct addrinfo *ai; 1337 querybuf buf, buf2; 1338 const char *name; 1339 const struct addrinfo *pai; 1340 struct addrinfo sentinel, *cur; 1341 struct res_target q, q2; 1342 1343 name = va_arg(ap, char *); 1344 pai = va_arg(ap, const struct addrinfo *); 1345 1346 memset(&q, 0, sizeof(q2)); 1347 memset(&q2, 0, sizeof(q2)); 1348 memset(&sentinel, 0, sizeof(sentinel)); 1349 cur = &sentinel; 1350 1351 switch (pai->ai_family) { 1352 case AF_UNSPEC: 1353 /* prefer IPv6 */ 1354 q.qclass = C_IN; 1355 q.qtype = T_AAAA; 1356 q.answer = buf.buf; 1357 q.anslen = sizeof(buf); 1358 q.next = &q2; 1359 q2.qclass = C_IN; 1360 q2.qtype = T_A; 1361 q2.answer = buf2.buf; 1362 q2.anslen = sizeof(buf2); 1363 break; 1364 case AF_INET: 1365 q.qclass = C_IN; 1366 q.qtype = T_A; 1367 q.answer = buf.buf; 1368 q.anslen = sizeof(buf); 1369 break; 1370 case AF_INET6: 1371 q.qclass = C_IN; 1372 q.qtype = T_AAAA; 1373 q.answer = buf.buf; 1374 q.anslen = sizeof(buf); 1375 break; 1376 default: 1377 return NS_UNAVAIL; 1378 } 1379 if (res_searchN(name, &q) < 0) 1380 return NS_NOTFOUND; 1381 ai = getanswer(&buf, q.n, q.name, q.qtype, pai); 1382 if (ai) { 1383 cur->ai_next = ai; 1384 while (cur && cur->ai_next) 1385 cur = cur->ai_next; 1386 } 1387 if (q.next) { 1388 ai = getanswer(&buf2, q2.n, q2.name, q2.qtype, pai); 1389 if (ai) 1390 cur->ai_next = ai; 1391 } 1392 if (sentinel.ai_next == NULL) 1393 switch (h_errno) { 1394 case HOST_NOT_FOUND: 1395 return NS_NOTFOUND; 1396 case TRY_AGAIN: 1397 return NS_TRYAGAIN; 1398 default: 1399 return NS_UNAVAIL; 1400 } 1401 *((struct addrinfo **)rv) = sentinel.ai_next; 1402 return NS_SUCCESS; 1403 } 1404 1405 static void 1406 _sethtent() 1407 { 1408 if (!hostf) 1409 hostf = fopen(_PATH_HOSTS, "r" ); 1410 else 1411 rewind(hostf); 1412 } 1413 1414 static void 1415 _endhtent() 1416 { 1417 if (hostf) { 1418 (void) fclose(hostf); 1419 hostf = NULL; 1420 } 1421 } 1422 1423 static struct addrinfo * 1424 _gethtent(name, pai) 1425 const char *name; 1426 const struct addrinfo *pai; 1427 { 1428 char *p; 1429 char *cp, *tname, *cname; 1430 struct addrinfo hints, *res0, *res; 1431 int error; 1432 const char *addr; 1433 char hostbuf[8*1024]; 1434 1435 if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) 1436 return (NULL); 1437 again: 1438 if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) 1439 return (NULL); 1440 if (*p == '#') 1441 goto again; 1442 if (!(cp = strpbrk(p, "#\n"))) 1443 goto again; 1444 *cp = '\0'; 1445 if (!(cp = strpbrk(p, " \t"))) 1446 goto again; 1447 *cp++ = '\0'; 1448 addr = p; 1449 cname = NULL; 1450 /* if this is not something we're looking for, skip it. */ 1451 while (cp && *cp) { 1452 if (*cp == ' ' || *cp == '\t') { 1453 cp++; 1454 continue; 1455 } 1456 tname = cp; 1457 if (cname == NULL) 1458 cname = cp; 1459 if ((cp = strpbrk(cp, " \t")) != NULL) 1460 *cp++ = '\0'; 1461 if (strcasecmp(name, tname) == 0) 1462 goto found; 1463 } 1464 goto again; 1465 1466 found: 1467 hints = *pai; 1468 hints.ai_flags = AI_NUMERICHOST; 1469 error = getaddrinfo(addr, NULL, &hints, &res0); 1470 if (error) 1471 goto again; 1472 #ifdef FILTER_V4MAPPED 1473 /* XXX should check all items in the chain */ 1474 if (res0->ai_family == AF_INET6 && 1475 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 1476 freeaddrinfo(res0); 1477 goto again; 1478 } 1479 #endif 1480 for (res = res0; res; res = res->ai_next) { 1481 /* cover it up */ 1482 res->ai_flags = pai->ai_flags; 1483 1484 if (pai->ai_flags & AI_CANONNAME) { 1485 if (get_canonname(pai, res, cname) != 0) { 1486 freeaddrinfo(res0); 1487 goto again; 1488 } 1489 } 1490 } 1491 return res0; 1492 } 1493 1494 /*ARGSUSED*/ 1495 static int 1496 _files_getaddrinfo(rv, cb_data, ap) 1497 void *rv; 1498 void *cb_data; 1499 va_list ap; 1500 { 1501 const char *name; 1502 const struct addrinfo *pai; 1503 struct addrinfo sentinel, *cur; 1504 struct addrinfo *p; 1505 1506 name = va_arg(ap, char *); 1507 pai = va_arg(ap, struct addrinfo *); 1508 1509 memset(&sentinel, 0, sizeof(sentinel)); 1510 cur = &sentinel; 1511 1512 _sethtent(); 1513 while ((p = _gethtent(name, pai)) != NULL) { 1514 cur->ai_next = p; 1515 while (cur && cur->ai_next) 1516 cur = cur->ai_next; 1517 } 1518 _endhtent(); 1519 1520 *((struct addrinfo **)rv) = sentinel.ai_next; 1521 if (sentinel.ai_next == NULL) 1522 return NS_NOTFOUND; 1523 return NS_SUCCESS; 1524 } 1525 1526 #ifdef YP 1527 static char *__ypdomain; 1528 1529 /*ARGSUSED*/ 1530 static struct addrinfo * 1531 _yphostent(line, pai) 1532 char *line; 1533 const struct addrinfo *pai; 1534 { 1535 struct addrinfo sentinel, *cur; 1536 struct addrinfo hints, *res, *res0; 1537 int error; 1538 char *p = line; 1539 const char *addr, *canonname; 1540 char *nextline; 1541 char *cp; 1542 1543 addr = canonname = NULL; 1544 1545 memset(&sentinel, 0, sizeof(sentinel)); 1546 cur = &sentinel; 1547 1548 nextline: 1549 /* terminate line */ 1550 cp = strchr(p, '\n'); 1551 if (cp) { 1552 *cp++ = '\0'; 1553 nextline = cp; 1554 } else 1555 nextline = NULL; 1556 1557 cp = strpbrk(p, " \t"); 1558 if (cp == NULL) { 1559 if (canonname == NULL) 1560 return (NULL); 1561 else 1562 goto done; 1563 } 1564 *cp++ = '\0'; 1565 1566 addr = p; 1567 1568 while (cp && *cp) { 1569 if (*cp == ' ' || *cp == '\t') { 1570 cp++; 1571 continue; 1572 } 1573 if (!canonname) 1574 canonname = cp; 1575 if ((cp = strpbrk(cp, " \t")) != NULL) 1576 *cp++ = '\0'; 1577 } 1578 1579 hints = *pai; 1580 hints.ai_flags = AI_NUMERICHOST; 1581 error = getaddrinfo(addr, NULL, &hints, &res0); 1582 if (error == 0) { 1583 for (res = res0; res; res = res->ai_next) { 1584 /* cover it up */ 1585 res->ai_flags = pai->ai_flags; 1586 1587 if (pai->ai_flags & AI_CANONNAME) 1588 (void)get_canonname(pai, res, canonname); 1589 } 1590 } else 1591 res0 = NULL; 1592 if (res0) { 1593 cur->ai_next = res0; 1594 while (cur && cur->ai_next) 1595 cur = cur->ai_next; 1596 } 1597 1598 if (nextline) { 1599 p = nextline; 1600 goto nextline; 1601 } 1602 1603 done: 1604 return sentinel.ai_next; 1605 } 1606 1607 /*ARGSUSED*/ 1608 static int 1609 _yp_getaddrinfo(rv, cb_data, ap) 1610 void *rv; 1611 void *cb_data; 1612 va_list ap; 1613 { 1614 struct addrinfo sentinel, *cur; 1615 struct addrinfo *ai = NULL; 1616 static char *__ypcurrent; 1617 int __ypcurrentlen, r; 1618 const char *name; 1619 const struct addrinfo *pai; 1620 1621 name = va_arg(ap, char *); 1622 pai = va_arg(ap, const struct addrinfo *); 1623 1624 memset(&sentinel, 0, sizeof(sentinel)); 1625 cur = &sentinel; 1626 1627 if (!__ypdomain) { 1628 if (_yp_check(&__ypdomain) == 0) 1629 return NS_UNAVAIL; 1630 } 1631 if (__ypcurrent) 1632 free(__ypcurrent); 1633 __ypcurrent = NULL; 1634 1635 /* hosts.byname is only for IPv4 (Solaris8) */ 1636 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 1637 r = yp_match(__ypdomain, "hosts.byname", name, 1638 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 1639 if (r == 0) { 1640 struct addrinfo ai4; 1641 1642 ai4 = *pai; 1643 ai4.ai_family = AF_INET; 1644 ai = _yphostent(__ypcurrent, &ai4); 1645 if (ai) { 1646 cur->ai_next = ai; 1647 while (cur && cur->ai_next) 1648 cur = cur->ai_next; 1649 } 1650 } 1651 } 1652 1653 /* ipnodes.byname can hold both IPv4/v6 */ 1654 r = yp_match(__ypdomain, "ipnodes.byname", name, 1655 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 1656 if (r == 0) { 1657 ai = _yphostent(__ypcurrent, pai); 1658 if (ai) { 1659 cur->ai_next = ai; 1660 while (cur && cur->ai_next) 1661 cur = cur->ai_next; 1662 } 1663 } 1664 1665 if (sentinel.ai_next == NULL) { 1666 h_errno = HOST_NOT_FOUND; 1667 return NS_NOTFOUND; 1668 } 1669 *((struct addrinfo **)rv) = sentinel.ai_next; 1670 return NS_SUCCESS; 1671 } 1672 #endif 1673 1674 /* resolver logic */ 1675 1676 extern const char *__hostalias(const char *); 1677 extern int h_errno; 1678 1679 /* 1680 * Formulate a normal query, send, and await answer. 1681 * Returned answer is placed in supplied buffer "answer". 1682 * Perform preliminary check of answer, returning success only 1683 * if no error is indicated and the answer count is nonzero. 1684 * Return the size of the response on success, -1 on error. 1685 * Error number is left in h_errno. 1686 * 1687 * Caller must parse answer and determine whether it answers the question. 1688 */ 1689 static int 1690 res_queryN(name, target) 1691 const char *name; /* domain name */ 1692 struct res_target *target; 1693 { 1694 u_char buf[MAXPACKET]; 1695 HEADER *hp; 1696 int n; 1697 struct res_target *t; 1698 int rcode; 1699 int ancount; 1700 1701 rcode = NOERROR; 1702 ancount = 0; 1703 1704 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 1705 h_errno = NETDB_INTERNAL; 1706 return (-1); 1707 } 1708 1709 for (t = target; t; t = t->next) { 1710 int class, type; 1711 u_char *answer; 1712 int anslen; 1713 1714 hp = (HEADER *)(void *)t->answer; 1715 hp->rcode = NOERROR; /* default */ 1716 1717 /* make it easier... */ 1718 class = t->qclass; 1719 type = t->qtype; 1720 answer = t->answer; 1721 anslen = t->anslen; 1722 #ifdef DEBUG 1723 if (_res.options & RES_DEBUG) 1724 printf(";; res_query(%s, %d, %d)\n", name, class, type); 1725 #endif 1726 1727 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, 1728 buf, sizeof(buf)); 1729 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) 1730 n = res_opt(n, buf, sizeof(buf), anslen); 1731 if (n <= 0) { 1732 #ifdef DEBUG 1733 if (_res.options & RES_DEBUG) 1734 printf(";; res_query: mkquery failed\n"); 1735 #endif 1736 h_errno = NO_RECOVERY; 1737 return (n); 1738 } 1739 n = res_send(buf, n, answer, anslen); 1740 #if 0 1741 if (n < 0) { 1742 #ifdef DEBUG 1743 if (_res.options & RES_DEBUG) 1744 printf(";; res_query: send error\n"); 1745 #endif 1746 h_errno = TRY_AGAIN; 1747 return (n); 1748 } 1749 #endif 1750 1751 if (n < 0 || hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 1752 rcode = hp->rcode; /* record most recent error */ 1753 #ifdef DEBUG 1754 if (_res.options & RES_DEBUG) 1755 printf(";; rcode = %d, ancount=%d\n", hp->rcode, 1756 ntohs(hp->ancount)); 1757 #endif 1758 continue; 1759 } 1760 1761 ancount += ntohs(hp->ancount); 1762 1763 t->n = n; 1764 } 1765 1766 if (ancount == 0) { 1767 switch (rcode) { 1768 case NXDOMAIN: 1769 h_errno = HOST_NOT_FOUND; 1770 break; 1771 case SERVFAIL: 1772 h_errno = TRY_AGAIN; 1773 break; 1774 case NOERROR: 1775 h_errno = NO_DATA; 1776 break; 1777 case FORMERR: 1778 case NOTIMP: 1779 case REFUSED: 1780 default: 1781 h_errno = NO_RECOVERY; 1782 break; 1783 } 1784 return (-1); 1785 } 1786 return (ancount); 1787 } 1788 1789 /* 1790 * Formulate a normal query, send, and retrieve answer in supplied buffer. 1791 * Return the size of the response on success, -1 on error. 1792 * If enabled, implement search rules until answer or unrecoverable failure 1793 * is detected. Error code, if any, is left in h_errno. 1794 */ 1795 static int 1796 res_searchN(name, target) 1797 const char *name; /* domain name */ 1798 struct res_target *target; 1799 { 1800 const char *cp, * const *domain; 1801 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 1802 u_int dots; 1803 int trailing_dot, ret, saved_herrno; 1804 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 1805 1806 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 1807 h_errno = NETDB_INTERNAL; 1808 return (-1); 1809 } 1810 1811 errno = 0; 1812 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 1813 dots = 0; 1814 for (cp = name; *cp; cp++) 1815 dots += (*cp == '.'); 1816 trailing_dot = 0; 1817 if (cp > name && *--cp == '.') 1818 trailing_dot++; 1819 1820 /* 1821 * if there aren't any dots, it could be a user-level alias 1822 */ 1823 if (!dots && (cp = __hostalias(name)) != NULL) 1824 return (res_queryN(cp, target)); 1825 1826 /* 1827 * If there are dots in the name already, let's just give it a try 1828 * 'as is'. The threshold can be set with the "ndots" option. 1829 */ 1830 saved_herrno = -1; 1831 if (dots >= _res.ndots) { 1832 ret = res_querydomainN(name, NULL, target); 1833 if (ret > 0) 1834 return (ret); 1835 saved_herrno = h_errno; 1836 tried_as_is++; 1837 } 1838 1839 /* 1840 * We do at least one level of search if 1841 * - there is no dot and RES_DEFNAME is set, or 1842 * - there is at least one dot, there is no trailing dot, 1843 * and RES_DNSRCH is set. 1844 */ 1845 if ((!dots && (_res.options & RES_DEFNAMES)) || 1846 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { 1847 int done = 0; 1848 1849 for (domain = (const char * const *)_res.dnsrch; 1850 *domain && !done; 1851 domain++) { 1852 1853 ret = res_querydomainN(name, *domain, target); 1854 if (ret > 0) 1855 return (ret); 1856 1857 /* 1858 * If no server present, give up. 1859 * If name isn't found in this domain, 1860 * keep trying higher domains in the search list 1861 * (if that's enabled). 1862 * On a NO_DATA error, keep trying, otherwise 1863 * a wildcard entry of another type could keep us 1864 * from finding this entry higher in the domain. 1865 * If we get some other error (negative answer or 1866 * server failure), then stop searching up, 1867 * but try the input name below in case it's 1868 * fully-qualified. 1869 */ 1870 if (errno == ECONNREFUSED) { 1871 h_errno = TRY_AGAIN; 1872 return (-1); 1873 } 1874 1875 switch (h_errno) { 1876 case NO_DATA: 1877 got_nodata++; 1878 /* FALLTHROUGH */ 1879 case HOST_NOT_FOUND: 1880 /* keep trying */ 1881 break; 1882 case TRY_AGAIN: 1883 if (hp->rcode == SERVFAIL) { 1884 /* try next search element, if any */ 1885 got_servfail++; 1886 break; 1887 } 1888 /* FALLTHROUGH */ 1889 default: 1890 /* anything else implies that we're done */ 1891 done++; 1892 } 1893 /* 1894 * if we got here for some reason other than DNSRCH, 1895 * we only wanted one iteration of the loop, so stop. 1896 */ 1897 if (!(_res.options & RES_DNSRCH)) 1898 done++; 1899 } 1900 } 1901 1902 /* 1903 * if we have not already tried the name "as is", do that now. 1904 * note that we do this regardless of how many dots were in the 1905 * name or whether it ends with a dot. 1906 */ 1907 if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) { 1908 ret = res_querydomainN(name, NULL, target); 1909 if (ret > 0) 1910 return (ret); 1911 } 1912 1913 /* 1914 * if we got here, we didn't satisfy the search. 1915 * if we did an initial full query, return that query's h_errno 1916 * (note that we wouldn't be here if that query had succeeded). 1917 * else if we ever got a nodata, send that back as the reason. 1918 * else send back meaningless h_errno, that being the one from 1919 * the last DNSRCH we did. 1920 */ 1921 if (saved_herrno != -1) 1922 h_errno = saved_herrno; 1923 else if (got_nodata) 1924 h_errno = NO_DATA; 1925 else if (got_servfail) 1926 h_errno = TRY_AGAIN; 1927 return (-1); 1928 } 1929 1930 /* 1931 * Perform a call on res_query on the concatenation of name and domain, 1932 * removing a trailing dot from name if domain is NULL. 1933 */ 1934 static int 1935 res_querydomainN(name, domain, target) 1936 const char *name, *domain; 1937 struct res_target *target; 1938 { 1939 char nbuf[MAXDNAME]; 1940 const char *longname = nbuf; 1941 size_t n, d; 1942 1943 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 1944 h_errno = NETDB_INTERNAL; 1945 return (-1); 1946 } 1947 #ifdef DEBUG 1948 if (_res.options & RES_DEBUG) 1949 printf(";; res_querydomain(%s, %s)\n", 1950 name, domain?domain:"<Nil>"); 1951 #endif 1952 if (domain == NULL) { 1953 /* 1954 * Check for trailing '.'; 1955 * copy without '.' if present. 1956 */ 1957 n = strlen(name); 1958 if (n >= MAXDNAME) { 1959 h_errno = NO_RECOVERY; 1960 return (-1); 1961 } 1962 if (n > 0 && name[--n] == '.') { 1963 strncpy(nbuf, name, n); 1964 nbuf[n] = '\0'; 1965 } else 1966 longname = name; 1967 } else { 1968 n = strlen(name); 1969 d = strlen(domain); 1970 if (n + d + 1 >= MAXDNAME) { 1971 h_errno = NO_RECOVERY; 1972 return (-1); 1973 } 1974 sprintf(nbuf, "%s.%s", name, domain); 1975 } 1976 return (res_queryN(longname, target)); 1977 } 1978