getaddrinfo.c revision 1.55.2.1
1 /* $NetBSD: getaddrinfo.c,v 1.55.2.1 2002/06/29 22:48:11 lukem Exp $ */ 2 /* $KAME: getaddrinfo.c,v 1.29 2000/08/31 17:26:57 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * Issues to be discussed: 35 * - Thread safe-ness must be checked. 36 * - Return values. There are nonstandard return values defined and used 37 * in the source code. This is because RFC2553 is silent about which error 38 * code must be returned for which situation. 39 * - IPv4 classful (shortened) form. RFC2553 is silent about it. XNET 5.2 40 * says to use inet_aton() to convert IPv4 numeric to binary (alows 41 * classful form as a result). 42 * current code - disallow classful form for IPv4 (due to use of inet_pton). 43 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 44 * invalid. 45 * current code - SEGV on freeaddrinfo(NULL) 46 * Note: 47 * - We use getipnodebyname() just for thread-safeness. There's no intent 48 * to let it do PF_UNSPEC (actually we never pass PF_UNSPEC to 49 * getipnodebyname(). 50 * - The code filters out AFs that are not supported by the kernel, 51 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 52 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 53 * in ai_flags? 54 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 55 * (1) what should we do against numeric hostname (2) what should we do 56 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 57 * non-loopback address configured? global address configured? 58 * - To avoid search order issue, we have a big amount of code duplicate 59 * from gethnamaddr.c and some other places. The issues that there's no 60 * lower layer function to lookup "IPv4 or IPv6" record. Calling 61 * gethostbyname2 from getaddrinfo will end up in wrong search order, as 62 * follows: 63 * - The code makes use of following calls when asked to resolver with 64 * ai_family = PF_UNSPEC: 65 * getipnodebyname(host, AF_INET6); 66 * getipnodebyname(host, AF_INET); 67 * This will result in the following queries if the node is configure to 68 * prefer /etc/hosts than DNS: 69 * lookup /etc/hosts for IPv6 address 70 * lookup DNS for IPv6 address 71 * lookup /etc/hosts for IPv4 address 72 * lookup DNS for IPv4 address 73 * which may not meet people's requirement. 74 * The right thing to happen is to have underlying layer which does 75 * PF_UNSPEC lookup (lookup both) and return chain of addrinfos. 76 * This would result in a bit of code duplicate with _dns_ghbyname() and 77 * friends. 78 */ 79 80 #include <sys/cdefs.h> 81 #if defined(LIBC_SCCS) && !defined(lint) 82 __RCSID("$NetBSD: getaddrinfo.c,v 1.55.2.1 2002/06/29 22:48:11 lukem Exp $"); 83 #endif /* LIBC_SCCS and not lint */ 84 85 #include "namespace.h" 86 #include <sys/types.h> 87 #include <sys/param.h> 88 #include <sys/socket.h> 89 #include <net/if.h> 90 #include <netinet/in.h> 91 #include <arpa/inet.h> 92 #include <arpa/nameser.h> 93 #include <assert.h> 94 #include <ctype.h> 95 #include <errno.h> 96 #include <netdb.h> 97 #include <resolv.h> 98 #include <stddef.h> 99 #include <stdio.h> 100 #include <stdlib.h> 101 #include <string.h> 102 #include <unistd.h> 103 104 #include <syslog.h> 105 #include <stdarg.h> 106 #include <nsswitch.h> 107 108 #ifdef YP 109 #include <rpc/rpc.h> 110 #include <rpcsvc/yp_prot.h> 111 #include <rpcsvc/ypclnt.h> 112 #endif 113 114 #ifdef __weak_alias 115 __weak_alias(getaddrinfo,_getaddrinfo) 116 __weak_alias(freeaddrinfo,_freeaddrinfo) 117 __weak_alias(gai_strerror,_gai_strerror) 118 #endif 119 120 #define SUCCESS 0 121 #define ANY 0 122 #define YES 1 123 #define NO 0 124 125 static const char in_addrany[] = { 0, 0, 0, 0 }; 126 static const char in_loopback[] = { 127, 0, 0, 1 }; 127 #ifdef INET6 128 static const char in6_addrany[] = { 129 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 130 }; 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 #endif 135 136 static const struct afd { 137 int a_af; 138 int a_addrlen; 139 int a_socklen; 140 int a_off; 141 const char *a_addrany; 142 const char *a_loopback; 143 int a_scoped; 144 } afdl [] = { 145 #ifdef INET6 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 #endif 151 {PF_INET, sizeof(struct in_addr), 152 sizeof(struct sockaddr_in), 153 offsetof(struct sockaddr_in, sin_addr), 154 in_addrany, in_loopback, 0}, 155 {0, 0, 0, 0, NULL, NULL, 0}, 156 }; 157 158 struct explore { 159 int e_af; 160 int e_socktype; 161 int e_protocol; 162 const char *e_protostr; 163 int e_wild; 164 #define WILD_AF(ex) ((ex)->e_wild & 0x01) 165 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 166 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 167 }; 168 169 static const struct explore explore[] = { 170 #if 0 171 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 172 #endif 173 #ifdef INET6 174 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 175 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 176 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 177 #endif 178 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 179 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 180 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 181 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 182 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 183 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, 184 { -1, 0, 0, NULL, 0 }, 185 }; 186 187 #ifdef INET6 188 #define PTON_MAX 16 189 #else 190 #define PTON_MAX 4 191 #endif 192 193 static const ns_src default_dns_files[] = { 194 { NSSRC_FILES, NS_SUCCESS }, 195 { NSSRC_DNS, NS_SUCCESS }, 196 { 0 } 197 }; 198 199 #if PACKETSZ > 1024 200 #define MAXPACKET PACKETSZ 201 #else 202 #define MAXPACKET 1024 203 #endif 204 205 typedef union { 206 HEADER hdr; 207 u_char buf[MAXPACKET]; 208 } querybuf; 209 210 struct res_target { 211 struct res_target *next; 212 const char *name; /* domain name */ 213 int qclass, qtype; /* class and type of query */ 214 u_char *answer; /* buffer to put answer */ 215 int anslen; /* size of answer buffer */ 216 int n; /* result length */ 217 }; 218 219 static int str_isnumber __P((const char *)); 220 static int explore_fqdn __P((const struct addrinfo *, const char *, 221 const char *, struct addrinfo **)); 222 static int explore_null __P((const struct addrinfo *, 223 const char *, struct addrinfo **)); 224 static int explore_numeric __P((const struct addrinfo *, const char *, 225 const char *, struct addrinfo **)); 226 static int explore_numeric_scope __P((const struct addrinfo *, const char *, 227 const char *, struct addrinfo **)); 228 static int get_canonname __P((const struct addrinfo *, 229 struct addrinfo *, const char *)); 230 static struct addrinfo *get_ai __P((const struct addrinfo *, 231 const struct afd *, const char *)); 232 static int get_portmatch __P((const struct addrinfo *, const char *)); 233 static int get_port __P((struct addrinfo *, const char *, int)); 234 static const struct afd *find_afd __P((int)); 235 #if 0 236 static int addrconfig __P((const struct addrinfo *)); 237 #endif 238 #ifdef INET6 239 static int ip6_str2scopeid __P((char *, struct sockaddr_in6 *)); 240 #endif 241 242 static struct addrinfo *getanswer __P((const querybuf *, int, const char *, int, 243 const struct addrinfo *)); 244 static int _dns_getaddrinfo __P((void *, void *, va_list)); 245 static void _sethtent __P((void)); 246 static void _endhtent __P((void)); 247 static struct addrinfo *_gethtent __P((const char *, const struct addrinfo *)); 248 static int _files_getaddrinfo __P((void *, void *, va_list)); 249 #ifdef YP 250 static struct addrinfo *_yphostent __P((char *, const struct addrinfo *)); 251 static int _yp_getaddrinfo __P((void *, void *, va_list)); 252 #endif 253 254 static int res_queryN __P((const char *, struct res_target *)); 255 static int res_searchN __P((const char *, struct res_target *)); 256 static int res_querydomainN __P((const char *, const char *, 257 struct res_target *)); 258 259 static const char * const ai_errlist[] = { 260 "Success", 261 "Address family for hostname not supported", /* EAI_ADDRFAMILY */ 262 "Temporary failure in name resolution", /* EAI_AGAIN */ 263 "Invalid value for ai_flags", /* EAI_BADFLAGS */ 264 "Non-recoverable failure in name resolution", /* EAI_FAIL */ 265 "ai_family not supported", /* EAI_FAMILY */ 266 "Memory allocation failure", /* EAI_MEMORY */ 267 "No address associated with hostname", /* EAI_NODATA */ 268 "hostname nor servname provided, or not known", /* EAI_NONAME */ 269 "servname not supported for ai_socktype", /* EAI_SERVICE */ 270 "ai_socktype not supported", /* EAI_SOCKTYPE */ 271 "System error returned in errno", /* EAI_SYSTEM */ 272 "Invalid value for hints", /* EAI_BADHINTS */ 273 "Resolved protocol is unknown", /* EAI_PROTOCOL */ 274 "Unknown error", /* EAI_MAX */ 275 }; 276 277 /* XXX macros that make external reference is BAD. */ 278 279 #define GET_AI(ai, afd, addr) \ 280 do { \ 281 /* external reference: pai, error, and label free */ \ 282 (ai) = get_ai(pai, (afd), (addr)); \ 283 if ((ai) == NULL) { \ 284 error = EAI_MEMORY; \ 285 goto free; \ 286 } \ 287 } while (/*CONSTCOND*/0) 288 289 #define GET_PORT(ai, serv) \ 290 do { \ 291 /* external reference: error and label free */ \ 292 error = get_port((ai), (serv), 0); \ 293 if (error != 0) \ 294 goto free; \ 295 } while (/*CONSTCOND*/0) 296 297 #define GET_CANONNAME(ai, str) \ 298 do { \ 299 /* external reference: pai, error and label free */ \ 300 error = get_canonname(pai, (ai), (str)); \ 301 if (error != 0) \ 302 goto free; \ 303 } while (/*CONSTCOND*/0) 304 305 #define ERR(err) \ 306 do { \ 307 /* external reference: error, and label bad */ \ 308 error = (err); \ 309 goto bad; \ 310 /*NOTREACHED*/ \ 311 } while (/*CONSTCOND*/0) 312 313 #define MATCH_FAMILY(x, y, w) \ 314 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 315 #define MATCH(x, y, w) \ 316 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 317 318 char * 319 gai_strerror(ecode) 320 int ecode; 321 { 322 if (ecode < 0 || ecode > EAI_MAX) 323 ecode = EAI_MAX; 324 /* LINTED const castaway */ 325 return (char *) ai_errlist[ecode]; 326 } 327 328 void 329 freeaddrinfo(ai) 330 struct addrinfo *ai; 331 { 332 struct addrinfo *next; 333 334 _DIAGASSERT(ai != NULL); 335 336 do { 337 next = ai->ai_next; 338 if (ai->ai_canonname) 339 free(ai->ai_canonname); 340 /* no need to free(ai->ai_addr) */ 341 free(ai); 342 ai = next; 343 } while (ai); 344 } 345 346 static int 347 str_isnumber(p) 348 const char *p; 349 { 350 char *ep; 351 352 _DIAGASSERT(p != NULL); 353 354 if (*p == '\0') 355 return NO; 356 ep = NULL; 357 (void)strtoul(p, &ep, 10); 358 if (ep && *ep == '\0') 359 return YES; 360 else 361 return NO; 362 } 363 364 int 365 getaddrinfo(hostname, servname, hints, res) 366 const char *hostname, *servname; 367 const struct addrinfo *hints; 368 struct addrinfo **res; 369 { 370 struct addrinfo sentinel; 371 struct addrinfo *cur; 372 int error = 0; 373 struct addrinfo ai; 374 struct addrinfo ai0; 375 struct addrinfo *pai; 376 const struct explore *ex; 377 378 /* hostname is allowed to be NULL */ 379 /* servname is allowed to be NULL */ 380 /* hints is allowed to be NULL */ 381 _DIAGASSERT(res != NULL); 382 383 memset(&sentinel, 0, sizeof(sentinel)); 384 cur = &sentinel; 385 pai = &ai; 386 pai->ai_flags = 0; 387 pai->ai_family = PF_UNSPEC; 388 pai->ai_socktype = ANY; 389 pai->ai_protocol = ANY; 390 pai->ai_addrlen = 0; 391 pai->ai_canonname = NULL; 392 pai->ai_addr = NULL; 393 pai->ai_next = NULL; 394 395 if (hostname == NULL && servname == NULL) 396 return EAI_NONAME; 397 if (hints) { 398 /* error check for hints */ 399 if (hints->ai_addrlen || hints->ai_canonname || 400 hints->ai_addr || hints->ai_next) 401 ERR(EAI_BADHINTS); /* xxx */ 402 if (hints->ai_flags & ~AI_MASK) 403 ERR(EAI_BADFLAGS); 404 switch (hints->ai_family) { 405 case PF_UNSPEC: 406 case PF_INET: 407 #ifdef INET6 408 case PF_INET6: 409 #endif 410 break; 411 default: 412 ERR(EAI_FAMILY); 413 } 414 memcpy(pai, hints, sizeof(*pai)); 415 416 /* 417 * if both socktype/protocol are specified, check if they 418 * are meaningful combination. 419 */ 420 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 421 for (ex = explore; ex->e_af >= 0; ex++) { 422 if (pai->ai_family != ex->e_af) 423 continue; 424 if (ex->e_socktype == ANY) 425 continue; 426 if (ex->e_protocol == ANY) 427 continue; 428 if (pai->ai_socktype == ex->e_socktype 429 && pai->ai_protocol != ex->e_protocol) { 430 ERR(EAI_BADHINTS); 431 } 432 } 433 } 434 } 435 436 /* 437 * check for special cases. (1) numeric servname is disallowed if 438 * socktype/protocol are left unspecified. (2) servname is disallowed 439 * for raw and other inet{,6} sockets. 440 */ 441 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 442 #ifdef PF_INET6 443 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 444 #endif 445 ) { 446 ai0 = *pai; /* backup *pai */ 447 448 if (pai->ai_family == PF_UNSPEC) { 449 #ifdef PF_INET6 450 pai->ai_family = PF_INET6; 451 #else 452 pai->ai_family = PF_INET; 453 #endif 454 } 455 error = get_portmatch(pai, servname); 456 if (error) 457 ERR(error); 458 459 *pai = ai0; 460 } 461 462 ai0 = *pai; 463 464 /* NULL hostname, or numeric hostname */ 465 for (ex = explore; ex->e_af >= 0; ex++) { 466 *pai = ai0; 467 468 /* PF_UNSPEC entries are prepared for DNS queries only */ 469 if (ex->e_af == PF_UNSPEC) 470 continue; 471 472 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 473 continue; 474 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 475 continue; 476 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 477 continue; 478 479 if (pai->ai_family == PF_UNSPEC) 480 pai->ai_family = ex->e_af; 481 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 482 pai->ai_socktype = ex->e_socktype; 483 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 484 pai->ai_protocol = ex->e_protocol; 485 486 if (hostname == NULL) 487 error = explore_null(pai, servname, &cur->ai_next); 488 else 489 error = explore_numeric_scope(pai, hostname, servname, &cur->ai_next); 490 491 if (error) 492 goto free; 493 494 while (cur && cur->ai_next) 495 cur = cur->ai_next; 496 } 497 498 /* 499 * XXX 500 * If numreic representation of AF1 can be interpreted as FQDN 501 * representation of AF2, we need to think again about the code below. 502 */ 503 if (sentinel.ai_next) 504 goto good; 505 506 if (pai->ai_flags & AI_NUMERICHOST) 507 ERR(EAI_NODATA); 508 if (hostname == NULL) 509 ERR(EAI_NODATA); 510 511 /* 512 * hostname as alphabetical name. 513 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 514 * outer loop by AFs. 515 */ 516 for (ex = explore; ex->e_af >= 0; ex++) { 517 *pai = ai0; 518 519 /* require exact match for family field */ 520 if (pai->ai_family != ex->e_af) 521 continue; 522 523 if (!MATCH(pai->ai_socktype, ex->e_socktype, 524 WILD_SOCKTYPE(ex))) { 525 continue; 526 } 527 if (!MATCH(pai->ai_protocol, ex->e_protocol, 528 WILD_PROTOCOL(ex))) { 529 continue; 530 } 531 532 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 533 pai->ai_socktype = ex->e_socktype; 534 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 535 pai->ai_protocol = ex->e_protocol; 536 537 error = explore_fqdn(pai, hostname, servname, 538 &cur->ai_next); 539 540 while (cur && cur->ai_next) 541 cur = cur->ai_next; 542 } 543 544 /* XXX */ 545 if (sentinel.ai_next) 546 error = 0; 547 548 if (error) 549 goto free; 550 if (error == 0) { 551 if (sentinel.ai_next) { 552 good: 553 *res = sentinel.ai_next; 554 return SUCCESS; 555 } else 556 error = EAI_FAIL; 557 } 558 free: 559 bad: 560 if (sentinel.ai_next) 561 freeaddrinfo(sentinel.ai_next); 562 *res = NULL; 563 return error; 564 } 565 566 /* 567 * FQDN hostname, DNS lookup 568 */ 569 static int 570 explore_fqdn(pai, hostname, servname, res) 571 const struct addrinfo *pai; 572 const char *hostname; 573 const char *servname; 574 struct addrinfo **res; 575 { 576 struct addrinfo *result; 577 struct addrinfo *cur; 578 int error = 0; 579 static const ns_dtab dtab[] = { 580 NS_FILES_CB(_files_getaddrinfo, NULL) 581 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 582 NS_NIS_CB(_yp_getaddrinfo, NULL) 583 { 0 } 584 }; 585 586 _DIAGASSERT(pai != NULL); 587 /* hostname may be NULL */ 588 /* servname may be NULL */ 589 _DIAGASSERT(res != NULL); 590 591 result = NULL; 592 593 #if 0 594 /* 595 * If AI_ADDRCONFIG is specified, check if we are expected to 596 * return the address family or not. 597 * XXX does not handle PF_UNSPEC - should filter out result from 598 * nsdispatch() 599 */ 600 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(pai)) 601 return 0; 602 #endif 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 _DIAGASSERT(pai != NULL); 658 /* servname may be NULL */ 659 _DIAGASSERT(res != NULL); 660 661 *res = NULL; 662 sentinel.ai_next = NULL; 663 cur = &sentinel; 664 665 /* 666 * filter out AFs that are not supported by the kernel 667 * XXX errno? 668 */ 669 s = socket(pai->ai_family, SOCK_DGRAM, 0); 670 if (s < 0) { 671 if (errno != EMFILE) 672 return 0; 673 } else 674 close(s); 675 676 /* 677 * if the servname does not match socktype/protocol, ignore it. 678 */ 679 if (get_portmatch(pai, servname) != 0) 680 return 0; 681 682 afd = find_afd(pai->ai_family); 683 if (afd == NULL) 684 return 0; 685 686 if (pai->ai_flags & AI_PASSIVE) { 687 GET_AI(cur->ai_next, afd, afd->a_addrany); 688 /* xxx meaningless? 689 * GET_CANONNAME(cur->ai_next, "anyaddr"); 690 */ 691 GET_PORT(cur->ai_next, servname); 692 } else { 693 GET_AI(cur->ai_next, afd, afd->a_loopback); 694 /* xxx meaningless? 695 * GET_CANONNAME(cur->ai_next, "localhost"); 696 */ 697 GET_PORT(cur->ai_next, servname); 698 } 699 cur = cur->ai_next; 700 701 *res = sentinel.ai_next; 702 return 0; 703 704 free: 705 if (sentinel.ai_next) 706 freeaddrinfo(sentinel.ai_next); 707 return error; 708 } 709 710 /* 711 * numeric hostname 712 */ 713 static int 714 explore_numeric(pai, hostname, servname, res) 715 const struct addrinfo *pai; 716 const char *hostname; 717 const char *servname; 718 struct addrinfo **res; 719 { 720 const struct afd *afd; 721 struct addrinfo *cur; 722 struct addrinfo sentinel; 723 int error; 724 char pton[PTON_MAX]; 725 726 _DIAGASSERT(pai != NULL); 727 /* hostname may be NULL */ 728 /* servname may be NULL */ 729 _DIAGASSERT(res != NULL); 730 731 *res = NULL; 732 sentinel.ai_next = NULL; 733 cur = &sentinel; 734 735 /* 736 * if the servname does not match socktype/protocol, ignore it. 737 */ 738 if (get_portmatch(pai, servname) != 0) 739 return 0; 740 741 afd = find_afd(pai->ai_family); 742 if (afd == NULL) 743 return 0; 744 745 switch (afd->a_af) { 746 #if 0 /*X/Open spec*/ 747 case AF_INET: 748 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 749 if (pai->ai_family == afd->a_af || 750 pai->ai_family == PF_UNSPEC /*?*/) { 751 GET_AI(cur->ai_next, afd, pton); 752 GET_PORT(cur->ai_next, servname); 753 while (cur && cur->ai_next) 754 cur = cur->ai_next; 755 } else 756 ERR(EAI_FAMILY); /*xxx*/ 757 } 758 break; 759 #endif 760 default: 761 if (inet_pton(afd->a_af, hostname, pton) == 1) { 762 if (pai->ai_family == afd->a_af || 763 pai->ai_family == PF_UNSPEC /*?*/) { 764 GET_AI(cur->ai_next, afd, pton); 765 GET_PORT(cur->ai_next, servname); 766 while (cur && cur->ai_next) 767 cur = cur->ai_next; 768 } else 769 ERR(EAI_FAMILY); /*xxx*/ 770 } 771 break; 772 } 773 774 *res = sentinel.ai_next; 775 return 0; 776 777 free: 778 bad: 779 if (sentinel.ai_next) 780 freeaddrinfo(sentinel.ai_next); 781 return error; 782 } 783 784 /* 785 * numeric hostname with scope 786 */ 787 static int 788 explore_numeric_scope(pai, hostname, servname, res) 789 const struct addrinfo *pai; 790 const char *hostname; 791 const char *servname; 792 struct addrinfo **res; 793 { 794 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 795 return explore_numeric(pai, hostname, servname, res); 796 #else 797 const struct afd *afd; 798 struct addrinfo *cur; 799 int error; 800 char *cp, *hostname2 = NULL, *scope, *addr; 801 struct sockaddr_in6 *sin6; 802 803 _DIAGASSERT(pai != NULL); 804 /* hostname may be NULL */ 805 /* servname may be NULL */ 806 _DIAGASSERT(res != NULL); 807 808 /* 809 * if the servname does not match socktype/protocol, ignore it. 810 */ 811 if (get_portmatch(pai, servname) != 0) 812 return 0; 813 814 afd = find_afd(pai->ai_family); 815 if (afd == NULL) 816 return 0; 817 818 if (!afd->a_scoped) 819 return explore_numeric(pai, hostname, servname, res); 820 821 cp = strchr(hostname, SCOPE_DELIMITER); 822 if (cp == NULL) 823 return explore_numeric(pai, hostname, servname, res); 824 825 #if 0 826 /* 827 * Handle special case of <scope id><delimiter><scoped_address> 828 */ 829 hostname2 = strdup(hostname); 830 if (hostname2 == NULL) 831 return EAI_MEMORY; 832 /* terminate at the delimiter */ 833 hostname2[cp - hostname] = '\0'; 834 scope = hostname2; 835 addr = cp + 1; 836 #else 837 /* 838 * Handle special case of <scoped_address><delimiter><scope id> 839 */ 840 hostname2 = strdup(hostname); 841 if (hostname2 == NULL) 842 return EAI_MEMORY; 843 /* terminate at the delimiter */ 844 hostname2[cp - hostname] = '\0'; 845 addr = hostname2; 846 scope = cp + 1; 847 #endif 848 849 error = explore_numeric(pai, addr, servname, res); 850 if (error == 0) { 851 int scopeid; 852 853 for (cur = *res; cur; cur = cur->ai_next) { 854 if (cur->ai_family != AF_INET6) 855 continue; 856 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 857 if ((scopeid = ip6_str2scopeid(scope, sin6)) == -1) { 858 free(hostname2); 859 return(EAI_NODATA); /* XXX: is return OK? */ 860 } 861 sin6->sin6_scope_id = scopeid; 862 } 863 } 864 865 free(hostname2); 866 867 return error; 868 #endif 869 } 870 871 static int 872 get_canonname(pai, ai, str) 873 const struct addrinfo *pai; 874 struct addrinfo *ai; 875 const char *str; 876 { 877 878 _DIAGASSERT(pai != NULL); 879 _DIAGASSERT(ai != NULL); 880 _DIAGASSERT(str != NULL); 881 882 if ((pai->ai_flags & AI_CANONNAME) != 0) { 883 ai->ai_canonname = (char *)malloc(strlen(str) + 1); 884 if (ai->ai_canonname == NULL) 885 return EAI_MEMORY; 886 strcpy(ai->ai_canonname, str); 887 } 888 return 0; 889 } 890 891 static struct addrinfo * 892 get_ai(pai, afd, addr) 893 const struct addrinfo *pai; 894 const struct afd *afd; 895 const char *addr; 896 { 897 char *p; 898 struct addrinfo *ai; 899 900 _DIAGASSERT(pai != NULL); 901 _DIAGASSERT(afd != NULL); 902 _DIAGASSERT(addr != NULL); 903 904 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 905 + (afd->a_socklen)); 906 if (ai == NULL) 907 return NULL; 908 909 memcpy(ai, pai, sizeof(struct addrinfo)); 910 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 911 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 912 ai->ai_addr->sa_len = afd->a_socklen; 913 ai->ai_addrlen = afd->a_socklen; 914 #if defined (__alpha__) || (defined(__i386__) && defined(_LP64)) || defined(__sparc64__) 915 ai->__ai_pad0 = 0; 916 #endif 917 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 918 p = (char *)(void *)(ai->ai_addr); 919 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 920 return ai; 921 } 922 923 static int 924 get_portmatch(ai, servname) 925 const struct addrinfo *ai; 926 const char *servname; 927 { 928 929 _DIAGASSERT(ai != NULL); 930 /* servname may be NULL */ 931 932 /* get_port does not touch first argument. when matchonly == 1. */ 933 /* LINTED const cast */ 934 return get_port((struct addrinfo *)ai, servname, 1); 935 } 936 937 static int 938 get_port(ai, servname, matchonly) 939 struct addrinfo *ai; 940 const char *servname; 941 int matchonly; 942 { 943 const char *proto; 944 struct servent *sp; 945 int port; 946 int allownumeric; 947 948 _DIAGASSERT(ai != NULL); 949 /* servname may be NULL */ 950 951 if (servname == NULL) 952 return 0; 953 switch (ai->ai_family) { 954 case AF_INET: 955 #ifdef AF_INET6 956 case AF_INET6: 957 #endif 958 break; 959 default: 960 return 0; 961 } 962 963 switch (ai->ai_socktype) { 964 case SOCK_RAW: 965 return EAI_SERVICE; 966 case SOCK_DGRAM: 967 case SOCK_STREAM: 968 allownumeric = 1; 969 break; 970 case ANY: 971 allownumeric = 0; 972 break; 973 default: 974 return EAI_SOCKTYPE; 975 } 976 977 if (str_isnumber(servname)) { 978 if (!allownumeric) 979 return EAI_SERVICE; 980 port = atoi(servname); 981 if (port < 0 || port > 65535) 982 return EAI_SERVICE; 983 port = htons(port); 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 #if 0 1036 /* 1037 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1038 * will take care of it. 1039 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1040 * if the code is right or not. 1041 */ 1042 static int 1043 addrconfig(pai) 1044 const struct addrinfo *pai; 1045 { 1046 int s; 1047 1048 _DIAGASSERT(pai != NULL); 1049 1050 /* XXX errno */ 1051 s = socket(pai->ai_family, SOCK_DGRAM, 0); 1052 if (s < 0) 1053 return 0; 1054 close(s); 1055 return 1; 1056 } 1057 #endif 1058 1059 #ifdef INET6 1060 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1061 static int 1062 ip6_str2scopeid(scope, sin6) 1063 char *scope; 1064 struct sockaddr_in6 *sin6; 1065 { 1066 int scopeid; 1067 struct in6_addr *a6; 1068 char *ep; 1069 1070 _DIAGASSERT(scope != NULL); 1071 _DIAGASSERT(sin6 != NULL); 1072 1073 a6 = &sin6->sin6_addr; 1074 1075 /* empty scopeid portion is invalid */ 1076 if (*scope == '\0') 1077 return -1; 1078 1079 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1080 /* 1081 * We currently assume a one-to-one mapping between links 1082 * and interfaces, so we simply use interface indices for 1083 * like-local scopes. 1084 */ 1085 scopeid = if_nametoindex(scope); 1086 if (scopeid == 0) 1087 goto trynumeric; 1088 return(scopeid); 1089 } 1090 1091 /* still unclear about literal, allow numeric only - placeholder */ 1092 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1093 goto trynumeric; 1094 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1095 goto trynumeric; 1096 else 1097 goto trynumeric; /* global */ 1098 1099 /* try to convert to a numeric id as a last resort */ 1100 trynumeric: 1101 scopeid = (int)strtoul(scope, &ep, 10); 1102 if (*ep == '\0') 1103 return scopeid; 1104 else 1105 return -1; 1106 } 1107 #endif 1108 1109 /* code duplicate with gethnamaddr.c */ 1110 1111 static const char AskedForGot[] = 1112 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1113 static FILE *hostf = NULL; 1114 1115 static struct addrinfo * 1116 getanswer(answer, anslen, qname, qtype, pai) 1117 const querybuf *answer; 1118 int anslen; 1119 const char *qname; 1120 int qtype; 1121 const struct addrinfo *pai; 1122 { 1123 struct addrinfo sentinel, *cur; 1124 struct addrinfo ai; 1125 const struct afd *afd; 1126 char *canonname; 1127 const HEADER *hp; 1128 const u_char *cp; 1129 int n; 1130 const u_char *eom; 1131 char *bp; 1132 int type, class, buflen, ancount, qdcount; 1133 int haveanswer, had_error; 1134 char tbuf[MAXDNAME]; 1135 int (*name_ok) __P((const char *)); 1136 char hostbuf[8*1024]; 1137 1138 _DIAGASSERT(answer != NULL); 1139 _DIAGASSERT(qname != NULL); 1140 _DIAGASSERT(pai != NULL); 1141 1142 memset(&sentinel, 0, sizeof(sentinel)); 1143 cur = &sentinel; 1144 1145 canonname = NULL; 1146 eom = answer->buf + anslen; 1147 switch (qtype) { 1148 case T_A: 1149 case T_AAAA: 1150 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1151 name_ok = res_hnok; 1152 break; 1153 default: 1154 return (NULL); /* XXX should be abort(); */ 1155 } 1156 /* 1157 * find first satisfactory answer 1158 */ 1159 hp = &answer->hdr; 1160 ancount = ntohs(hp->ancount); 1161 qdcount = ntohs(hp->qdcount); 1162 bp = hostbuf; 1163 buflen = sizeof hostbuf; 1164 cp = answer->buf + HFIXEDSZ; 1165 if (qdcount != 1) { 1166 h_errno = NO_RECOVERY; 1167 return (NULL); 1168 } 1169 n = dn_expand(answer->buf, eom, cp, bp, buflen); 1170 if ((n < 0) || !(*name_ok)(bp)) { 1171 h_errno = NO_RECOVERY; 1172 return (NULL); 1173 } 1174 cp += n + QFIXEDSZ; 1175 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1176 /* res_send() has already verified that the query name is the 1177 * same as the one we sent; this just gets the expanded name 1178 * (i.e., with the succeeding search-domain tacked on). 1179 */ 1180 n = strlen(bp) + 1; /* for the \0 */ 1181 if (n >= MAXHOSTNAMELEN) { 1182 h_errno = NO_RECOVERY; 1183 return (NULL); 1184 } 1185 canonname = bp; 1186 bp += n; 1187 buflen -= n; 1188 /* The qname can be abbreviated, but h_name is now absolute. */ 1189 qname = canonname; 1190 } 1191 haveanswer = 0; 1192 had_error = 0; 1193 while (ancount-- > 0 && cp < eom && !had_error) { 1194 n = dn_expand(answer->buf, eom, cp, bp, buflen); 1195 if ((n < 0) || !(*name_ok)(bp)) { 1196 had_error++; 1197 continue; 1198 } 1199 cp += n; /* name */ 1200 type = _getshort(cp); 1201 cp += INT16SZ; /* type */ 1202 class = _getshort(cp); 1203 cp += INT16SZ + INT32SZ; /* class, TTL */ 1204 n = _getshort(cp); 1205 cp += INT16SZ; /* len */ 1206 if (class != C_IN) { 1207 /* XXX - debug? syslog? */ 1208 cp += n; 1209 continue; /* XXX - had_error++ ? */ 1210 } 1211 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1212 type == T_CNAME) { 1213 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1214 if ((n < 0) || !(*name_ok)(tbuf)) { 1215 had_error++; 1216 continue; 1217 } 1218 cp += n; 1219 /* Get canonical name. */ 1220 n = strlen(tbuf) + 1; /* for the \0 */ 1221 if (n > buflen || n >= MAXHOSTNAMELEN) { 1222 had_error++; 1223 continue; 1224 } 1225 strcpy(bp, tbuf); 1226 canonname = bp; 1227 bp += n; 1228 buflen -= n; 1229 continue; 1230 } 1231 if (qtype == T_ANY) { 1232 if (!(type == T_A || type == T_AAAA)) { 1233 cp += n; 1234 continue; 1235 } 1236 } else if (type != qtype) { 1237 if (type != T_KEY && type != T_SIG) 1238 syslog(LOG_NOTICE|LOG_AUTH, 1239 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1240 qname, p_class(C_IN), p_type(qtype), 1241 p_type(type)); 1242 cp += n; 1243 continue; /* XXX - had_error++ ? */ 1244 } 1245 switch (type) { 1246 case T_A: 1247 case T_AAAA: 1248 if (strcasecmp(canonname, bp) != 0) { 1249 syslog(LOG_NOTICE|LOG_AUTH, 1250 AskedForGot, canonname, bp); 1251 cp += n; 1252 continue; /* XXX - had_error++ ? */ 1253 } 1254 if (type == T_A && n != INADDRSZ) { 1255 cp += n; 1256 continue; 1257 } 1258 if (type == T_AAAA && n != IN6ADDRSZ) { 1259 cp += n; 1260 continue; 1261 } 1262 if (!haveanswer) { 1263 int nn; 1264 1265 canonname = bp; 1266 nn = strlen(bp) + 1; /* for the \0 */ 1267 bp += nn; 1268 buflen -= nn; 1269 } 1270 1271 /* don't overwrite pai */ 1272 ai = *pai; 1273 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1274 afd = find_afd(ai.ai_family); 1275 if (afd == NULL) { 1276 cp += n; 1277 continue; 1278 } 1279 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1280 if (cur->ai_next == NULL) 1281 had_error++; 1282 while (cur && cur->ai_next) 1283 cur = cur->ai_next; 1284 cp += n; 1285 break; 1286 default: 1287 abort(); 1288 } 1289 if (!had_error) 1290 haveanswer++; 1291 } 1292 if (haveanswer) { 1293 if (!canonname) 1294 (void)get_canonname(pai, sentinel.ai_next, qname); 1295 else 1296 (void)get_canonname(pai, sentinel.ai_next, canonname); 1297 h_errno = NETDB_SUCCESS; 1298 return sentinel.ai_next; 1299 } 1300 1301 h_errno = NO_RECOVERY; 1302 return NULL; 1303 } 1304 1305 /*ARGSUSED*/ 1306 static int 1307 _dns_getaddrinfo(rv, cb_data, ap) 1308 void *rv; 1309 void *cb_data; 1310 va_list ap; 1311 { 1312 struct addrinfo *ai; 1313 querybuf buf, buf2; 1314 const char *name; 1315 const struct addrinfo *pai; 1316 struct addrinfo sentinel, *cur; 1317 struct res_target q, q2; 1318 1319 name = va_arg(ap, char *); 1320 pai = va_arg(ap, const struct addrinfo *); 1321 1322 memset(&q, 0, sizeof(q2)); 1323 memset(&q2, 0, sizeof(q2)); 1324 memset(&sentinel, 0, sizeof(sentinel)); 1325 cur = &sentinel; 1326 1327 switch (pai->ai_family) { 1328 case AF_UNSPEC: 1329 /* prefer IPv6 */ 1330 q.name = name; 1331 q.qclass = C_IN; 1332 q.qtype = T_AAAA; 1333 q.answer = buf.buf; 1334 q.anslen = sizeof(buf); 1335 q.next = &q2; 1336 q2.name = name; 1337 q2.qclass = C_IN; 1338 q2.qtype = T_A; 1339 q2.answer = buf2.buf; 1340 q2.anslen = sizeof(buf2); 1341 break; 1342 case AF_INET: 1343 q.name = name; 1344 q.qclass = C_IN; 1345 q.qtype = T_A; 1346 q.answer = buf.buf; 1347 q.anslen = sizeof(buf); 1348 break; 1349 case AF_INET6: 1350 q.name = name; 1351 q.qclass = C_IN; 1352 q.qtype = T_AAAA; 1353 q.answer = buf.buf; 1354 q.anslen = sizeof(buf); 1355 break; 1356 default: 1357 return NS_UNAVAIL; 1358 } 1359 if (res_searchN(name, &q) < 0) 1360 return NS_NOTFOUND; 1361 ai = getanswer(&buf, q.n, q.name, q.qtype, pai); 1362 if (ai) { 1363 cur->ai_next = ai; 1364 while (cur && cur->ai_next) 1365 cur = cur->ai_next; 1366 } 1367 if (q.next) { 1368 ai = getanswer(&buf2, q2.n, q2.name, q2.qtype, pai); 1369 if (ai) 1370 cur->ai_next = ai; 1371 } 1372 if (sentinel.ai_next == NULL) 1373 switch (h_errno) { 1374 case HOST_NOT_FOUND: 1375 return NS_NOTFOUND; 1376 case TRY_AGAIN: 1377 return NS_TRYAGAIN; 1378 default: 1379 return NS_UNAVAIL; 1380 } 1381 *((struct addrinfo **)rv) = sentinel.ai_next; 1382 return NS_SUCCESS; 1383 } 1384 1385 static void 1386 _sethtent() 1387 { 1388 1389 if (!hostf) 1390 hostf = fopen(_PATH_HOSTS, "r" ); 1391 else 1392 rewind(hostf); 1393 } 1394 1395 static void 1396 _endhtent() 1397 { 1398 1399 if (hostf) { 1400 (void) fclose(hostf); 1401 hostf = NULL; 1402 } 1403 } 1404 1405 static struct addrinfo * 1406 _gethtent(name, pai) 1407 const char *name; 1408 const struct addrinfo *pai; 1409 { 1410 char *p; 1411 char *cp, *tname, *cname; 1412 struct addrinfo hints, *res0, *res; 1413 int error; 1414 const char *addr; 1415 char hostbuf[8*1024]; 1416 1417 _DIAGASSERT(name != NULL); 1418 _DIAGASSERT(pai != NULL); 1419 1420 if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) 1421 return (NULL); 1422 again: 1423 if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) 1424 return (NULL); 1425 if (*p == '#') 1426 goto again; 1427 if (!(cp = strpbrk(p, "#\n"))) 1428 goto again; 1429 *cp = '\0'; 1430 if (!(cp = strpbrk(p, " \t"))) 1431 goto again; 1432 *cp++ = '\0'; 1433 addr = p; 1434 /* if this is not something we're looking for, skip it. */ 1435 cname = NULL; 1436 while (cp && *cp) { 1437 if (*cp == ' ' || *cp == '\t') { 1438 cp++; 1439 continue; 1440 } 1441 if (!cname) 1442 cname = cp; 1443 tname = cp; 1444 if ((cp = strpbrk(cp, " \t")) != NULL) 1445 *cp++ = '\0'; 1446 if (strcasecmp(name, tname) == 0) 1447 goto found; 1448 } 1449 goto again; 1450 1451 found: 1452 hints = *pai; 1453 hints.ai_flags = AI_NUMERICHOST; 1454 error = getaddrinfo(addr, NULL, &hints, &res0); 1455 if (error) 1456 goto again; 1457 for (res = res0; res; res = res->ai_next) { 1458 /* cover it up */ 1459 res->ai_flags = pai->ai_flags; 1460 1461 if (pai->ai_flags & AI_CANONNAME) { 1462 if (get_canonname(pai, res, cname) != 0) { 1463 freeaddrinfo(res0); 1464 goto again; 1465 } 1466 } 1467 } 1468 return res0; 1469 } 1470 1471 /*ARGSUSED*/ 1472 static int 1473 _files_getaddrinfo(rv, cb_data, ap) 1474 void *rv; 1475 void *cb_data; 1476 va_list ap; 1477 { 1478 const char *name; 1479 const struct addrinfo *pai; 1480 struct addrinfo sentinel, *cur; 1481 struct addrinfo *p; 1482 1483 name = va_arg(ap, char *); 1484 pai = va_arg(ap, struct addrinfo *); 1485 1486 memset(&sentinel, 0, sizeof(sentinel)); 1487 cur = &sentinel; 1488 1489 _sethtent(); 1490 while ((p = _gethtent(name, pai)) != NULL) { 1491 cur->ai_next = p; 1492 while (cur && cur->ai_next) 1493 cur = cur->ai_next; 1494 } 1495 _endhtent(); 1496 1497 *((struct addrinfo **)rv) = sentinel.ai_next; 1498 if (sentinel.ai_next == NULL) 1499 return NS_NOTFOUND; 1500 return NS_SUCCESS; 1501 } 1502 1503 #ifdef YP 1504 static char *__ypdomain; 1505 1506 /*ARGSUSED*/ 1507 static struct addrinfo * 1508 _yphostent(line, pai) 1509 char *line; 1510 const struct addrinfo *pai; 1511 { 1512 struct addrinfo sentinel, *cur; 1513 struct addrinfo hints, *res, *res0; 1514 int error; 1515 char *p; 1516 const char *addr, *canonname; 1517 char *nextline; 1518 char *cp; 1519 1520 _DIAGASSERT(line != NULL); 1521 _DIAGASSERT(pai != NULL); 1522 1523 p = line; 1524 addr = canonname = NULL; 1525 1526 memset(&sentinel, 0, sizeof(sentinel)); 1527 cur = &sentinel; 1528 1529 nextline: 1530 /* terminate line */ 1531 cp = strchr(p, '\n'); 1532 if (cp) { 1533 *cp++ = '\0'; 1534 nextline = cp; 1535 } else 1536 nextline = NULL; 1537 1538 cp = strpbrk(p, " \t"); 1539 if (cp == NULL) { 1540 if (canonname == NULL) 1541 return (NULL); 1542 else 1543 goto done; 1544 } 1545 *cp++ = '\0'; 1546 1547 addr = p; 1548 1549 while (cp && *cp) { 1550 if (*cp == ' ' || *cp == '\t') { 1551 cp++; 1552 continue; 1553 } 1554 if (!canonname) 1555 canonname = cp; 1556 if ((cp = strpbrk(cp, " \t")) != NULL) 1557 *cp++ = '\0'; 1558 } 1559 1560 hints = *pai; 1561 hints.ai_flags = AI_NUMERICHOST; 1562 error = getaddrinfo(addr, NULL, &hints, &res0); 1563 if (error == 0) { 1564 for (res = res0; res; res = res->ai_next) { 1565 /* cover it up */ 1566 res->ai_flags = pai->ai_flags; 1567 1568 if (pai->ai_flags & AI_CANONNAME) 1569 (void)get_canonname(pai, res, canonname); 1570 } 1571 } else 1572 res0 = NULL; 1573 if (res0) { 1574 cur->ai_next = res0; 1575 while (cur && cur->ai_next) 1576 cur = cur->ai_next; 1577 } 1578 1579 if (nextline) { 1580 p = nextline; 1581 goto nextline; 1582 } 1583 1584 done: 1585 return sentinel.ai_next; 1586 } 1587 1588 /*ARGSUSED*/ 1589 static int 1590 _yp_getaddrinfo(rv, cb_data, ap) 1591 void *rv; 1592 void *cb_data; 1593 va_list ap; 1594 { 1595 struct addrinfo sentinel, *cur; 1596 struct addrinfo *ai = NULL; 1597 static char *__ypcurrent; 1598 int __ypcurrentlen, r; 1599 const char *name; 1600 const struct addrinfo *pai; 1601 1602 name = va_arg(ap, char *); 1603 pai = va_arg(ap, const struct addrinfo *); 1604 1605 memset(&sentinel, 0, sizeof(sentinel)); 1606 cur = &sentinel; 1607 1608 if (!__ypdomain) { 1609 if (_yp_check(&__ypdomain) == 0) 1610 return NS_UNAVAIL; 1611 } 1612 if (__ypcurrent) 1613 free(__ypcurrent); 1614 __ypcurrent = NULL; 1615 1616 /* hosts.byname is only for IPv4 (Solaris8) */ 1617 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 1618 r = yp_match(__ypdomain, "hosts.byname", name, 1619 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 1620 if (r == 0) { 1621 struct addrinfo ai4; 1622 1623 ai4 = *pai; 1624 ai4.ai_family = AF_INET; 1625 ai = _yphostent(__ypcurrent, &ai4); 1626 if (ai) { 1627 cur->ai_next = ai; 1628 while (cur && cur->ai_next) 1629 cur = cur->ai_next; 1630 } 1631 } 1632 } 1633 1634 /* ipnodes.byname can hold both IPv4/v6 */ 1635 r = yp_match(__ypdomain, "ipnodes.byname", name, 1636 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 1637 if (r == 0) { 1638 ai = _yphostent(__ypcurrent, pai); 1639 if (ai) { 1640 cur->ai_next = ai; 1641 while (cur && cur->ai_next) 1642 cur = cur->ai_next; 1643 } 1644 } 1645 1646 if (sentinel.ai_next == NULL) { 1647 h_errno = HOST_NOT_FOUND; 1648 return NS_NOTFOUND; 1649 } 1650 *((struct addrinfo **)rv) = sentinel.ai_next; 1651 return NS_SUCCESS; 1652 } 1653 #endif 1654 1655 /* resolver logic */ 1656 1657 /* 1658 * Formulate a normal query, send, and await answer. 1659 * Returned answer is placed in supplied buffer "answer". 1660 * Perform preliminary check of answer, returning success only 1661 * if no error is indicated and the answer count is nonzero. 1662 * Return the size of the response on success, -1 on error. 1663 * Error number is left in h_errno. 1664 * 1665 * Caller must parse answer and determine whether it answers the question. 1666 */ 1667 static int 1668 res_queryN(name, target) 1669 const char *name; /* domain name */ 1670 struct res_target *target; 1671 { 1672 u_char buf[MAXPACKET]; 1673 HEADER *hp; 1674 int n; 1675 struct res_target *t; 1676 int rcode; 1677 int ancount; 1678 1679 _DIAGASSERT(name != NULL); 1680 /* XXX: target may be NULL??? */ 1681 1682 rcode = NOERROR; 1683 ancount = 0; 1684 1685 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 1686 h_errno = NETDB_INTERNAL; 1687 return (-1); 1688 } 1689 1690 for (t = target; t; t = t->next) { 1691 int class, type; 1692 u_char *answer; 1693 int anslen; 1694 1695 hp = (HEADER *)(void *)t->answer; 1696 hp->rcode = NOERROR; /* default */ 1697 1698 /* make it easier... */ 1699 class = t->qclass; 1700 type = t->qtype; 1701 answer = t->answer; 1702 anslen = t->anslen; 1703 #ifdef DEBUG 1704 if (_res.options & RES_DEBUG) 1705 printf(";; res_query(%s, %d, %d)\n", name, class, type); 1706 #endif 1707 1708 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, 1709 buf, sizeof(buf)); 1710 #ifdef RES_USE_EDNS0 1711 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) 1712 n = res_opt(n, buf, sizeof(buf), anslen); 1713 #endif 1714 if (n <= 0) { 1715 #ifdef DEBUG 1716 if (_res.options & RES_DEBUG) 1717 printf(";; res_query: mkquery failed\n"); 1718 #endif 1719 h_errno = NO_RECOVERY; 1720 return (n); 1721 } 1722 n = res_send(buf, n, answer, anslen); 1723 #if 0 1724 if (n < 0) { 1725 #ifdef DEBUG 1726 if (_res.options & RES_DEBUG) 1727 printf(";; res_query: send error\n"); 1728 #endif 1729 h_errno = TRY_AGAIN; 1730 return (n); 1731 } 1732 #endif 1733 1734 if (n < 0 || hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 1735 rcode = hp->rcode; /* record most recent error */ 1736 #ifdef DEBUG 1737 if (_res.options & RES_DEBUG) 1738 printf(";; rcode = %d, ancount=%d\n", hp->rcode, 1739 ntohs(hp->ancount)); 1740 #endif 1741 continue; 1742 } 1743 1744 ancount += ntohs(hp->ancount); 1745 1746 t->n = n; 1747 } 1748 1749 if (ancount == 0) { 1750 switch (rcode) { 1751 case NXDOMAIN: 1752 h_errno = HOST_NOT_FOUND; 1753 break; 1754 case SERVFAIL: 1755 h_errno = TRY_AGAIN; 1756 break; 1757 case NOERROR: 1758 h_errno = NO_DATA; 1759 break; 1760 case FORMERR: 1761 case NOTIMP: 1762 case REFUSED: 1763 default: 1764 h_errno = NO_RECOVERY; 1765 break; 1766 } 1767 return (-1); 1768 } 1769 return (ancount); 1770 } 1771 1772 /* 1773 * Formulate a normal query, send, and retrieve answer in supplied buffer. 1774 * Return the size of the response on success, -1 on error. 1775 * If enabled, implement search rules until answer or unrecoverable failure 1776 * is detected. Error code, if any, is left in h_errno. 1777 */ 1778 static int 1779 res_searchN(name, target) 1780 const char *name; /* domain name */ 1781 struct res_target *target; 1782 { 1783 const char *cp, * const *domain; 1784 HEADER *hp; 1785 u_int dots; 1786 int trailing_dot, ret, saved_herrno; 1787 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 1788 1789 _DIAGASSERT(name != NULL); 1790 _DIAGASSERT(target != NULL); 1791 1792 hp = (HEADER *)(void *)target->answer; /*XXX*/ 1793 1794 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 1795 h_errno = NETDB_INTERNAL; 1796 return (-1); 1797 } 1798 1799 errno = 0; 1800 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 1801 dots = 0; 1802 for (cp = name; *cp; cp++) 1803 dots += (*cp == '.'); 1804 trailing_dot = 0; 1805 if (cp > name && *--cp == '.') 1806 trailing_dot++; 1807 1808 /* 1809 * if there aren't any dots, it could be a user-level alias 1810 */ 1811 if (!dots && (cp = __hostalias(name)) != NULL) 1812 return (res_queryN(cp, target)); 1813 1814 /* 1815 * If there are dots in the name already, let's just give it a try 1816 * 'as is'. The threshold can be set with the "ndots" option. 1817 */ 1818 saved_herrno = -1; 1819 if (dots >= _res.ndots) { 1820 ret = res_querydomainN(name, NULL, target); 1821 if (ret > 0) 1822 return (ret); 1823 saved_herrno = h_errno; 1824 tried_as_is++; 1825 } 1826 1827 /* 1828 * We do at least one level of search if 1829 * - there is no dot and RES_DEFNAME is set, or 1830 * - there is at least one dot, there is no trailing dot, 1831 * and RES_DNSRCH is set. 1832 */ 1833 if ((!dots && (_res.options & RES_DEFNAMES)) || 1834 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { 1835 int done = 0; 1836 1837 for (domain = (const char * const *)_res.dnsrch; 1838 *domain && !done; 1839 domain++) { 1840 1841 ret = res_querydomainN(name, *domain, target); 1842 if (ret > 0) 1843 return (ret); 1844 1845 /* 1846 * If no server present, give up. 1847 * If name isn't found in this domain, 1848 * keep trying higher domains in the search list 1849 * (if that's enabled). 1850 * On a NO_DATA error, keep trying, otherwise 1851 * a wildcard entry of another type could keep us 1852 * from finding this entry higher in the domain. 1853 * If we get some other error (negative answer or 1854 * server failure), then stop searching up, 1855 * but try the input name below in case it's 1856 * fully-qualified. 1857 */ 1858 if (errno == ECONNREFUSED) { 1859 h_errno = TRY_AGAIN; 1860 return (-1); 1861 } 1862 1863 switch (h_errno) { 1864 case NO_DATA: 1865 got_nodata++; 1866 /* FALLTHROUGH */ 1867 case HOST_NOT_FOUND: 1868 /* keep trying */ 1869 break; 1870 case TRY_AGAIN: 1871 if (hp->rcode == SERVFAIL) { 1872 /* try next search element, if any */ 1873 got_servfail++; 1874 break; 1875 } 1876 /* FALLTHROUGH */ 1877 default: 1878 /* anything else implies that we're done */ 1879 done++; 1880 } 1881 /* 1882 * if we got here for some reason other than DNSRCH, 1883 * we only wanted one iteration of the loop, so stop. 1884 */ 1885 if (!(_res.options & RES_DNSRCH)) 1886 done++; 1887 } 1888 } 1889 1890 /* 1891 * if we have not already tried the name "as is", do that now. 1892 * note that we do this regardless of how many dots were in the 1893 * name or whether it ends with a dot. 1894 */ 1895 if (!tried_as_is) { 1896 ret = res_querydomainN(name, NULL, target); 1897 if (ret > 0) 1898 return (ret); 1899 } 1900 1901 /* 1902 * if we got here, we didn't satisfy the search. 1903 * if we did an initial full query, return that query's h_errno 1904 * (note that we wouldn't be here if that query had succeeded). 1905 * else if we ever got a nodata, send that back as the reason. 1906 * else send back meaningless h_errno, that being the one from 1907 * the last DNSRCH we did. 1908 */ 1909 if (saved_herrno != -1) 1910 h_errno = saved_herrno; 1911 else if (got_nodata) 1912 h_errno = NO_DATA; 1913 else if (got_servfail) 1914 h_errno = TRY_AGAIN; 1915 return (-1); 1916 } 1917 1918 /* 1919 * Perform a call on res_query on the concatenation of name and domain, 1920 * removing a trailing dot from name if domain is NULL. 1921 */ 1922 static int 1923 res_querydomainN(name, domain, target) 1924 const char *name, *domain; 1925 struct res_target *target; 1926 { 1927 char nbuf[MAXDNAME]; 1928 const char *longname = nbuf; 1929 size_t n, d; 1930 1931 _DIAGASSERT(name != NULL); 1932 /* XXX: target may be NULL??? */ 1933 1934 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 1935 h_errno = NETDB_INTERNAL; 1936 return (-1); 1937 } 1938 #ifdef DEBUG 1939 if (_res.options & RES_DEBUG) 1940 printf(";; res_querydomain(%s, %s)\n", 1941 name, domain?domain:"<Nil>"); 1942 #endif 1943 if (domain == NULL) { 1944 /* 1945 * Check for trailing '.'; 1946 * copy without '.' if present. 1947 */ 1948 n = strlen(name); 1949 if (n >= MAXDNAME) { 1950 h_errno = NO_RECOVERY; 1951 return (-1); 1952 } 1953 if (n > 0 && name[--n] == '.') { 1954 strncpy(nbuf, name, n); 1955 nbuf[n] = '\0'; 1956 } else 1957 longname = name; 1958 } else { 1959 n = strlen(name); 1960 d = strlen(domain); 1961 if (n + d + 1 >= MAXDNAME) { 1962 h_errno = NO_RECOVERY; 1963 return (-1); 1964 } 1965 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 1966 } 1967 return (res_queryN(longname, target)); 1968 } 1969
Indexes created Tue Sep 30 11:09:46 GMT 2025