1 /* $NetBSD: getaddrinfo.c,v 1.127 2024/01/21 12:58:10 kre 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 * - Return values. There are nonstandard return values defined and used 36 * in the source code. This is because RFC2553 is silent about which error 37 * code must be returned for which situation. 38 * - IPv4 classful (shortened) form. RFC2553 is silent about it. XNET 5.2 39 * says to use inet_aton() to convert IPv4 numeric to binary (allows 40 * classful form as a result). 41 * current code - disallow classful form for IPv4 (due to use of inet_pton). 42 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 43 * invalid. 44 * current code - SEGV on freeaddrinfo(NULL) 45 * Note: 46 * - The code filters out AFs that are not supported by the kernel, 47 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 48 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 49 * in ai_flags? 50 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 51 * (1) what should we do against numeric hostname (2) what should we do 52 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 53 * non-loopback address configured? global address configured? 54 */ 55 56 #include <sys/cdefs.h> 57 #if defined(LIBC_SCCS) && !defined(lint) 58 __RCSID("$NetBSD: getaddrinfo.c,v 1.127 2024/01/21 12:58:10 kre Exp $"); 59 #endif /* LIBC_SCCS and not lint */ 60 61 #ifndef RUMP_ACTION 62 #include "namespace.h" 63 #endif 64 #include <sys/types.h> 65 #include <sys/param.h> 66 #include <sys/socket.h> 67 #include <sys/ioctl.h> 68 #include <sys/sysctl.h> 69 #include <net/if.h> 70 #include <netinet/in.h> 71 #include <netinet6/in6_var.h> 72 #include <arpa/inet.h> 73 #include <arpa/nameser.h> 74 #include <assert.h> 75 #include <ctype.h> 76 #include <errno.h> 77 #include <netdb.h> 78 #include <resolv.h> 79 #include <stddef.h> 80 #include <stdio.h> 81 #include <stdlib.h> 82 #include <string.h> 83 #include <unistd.h> 84 #include <ifaddrs.h> 85 86 #include <syslog.h> 87 #include <stdarg.h> 88 #include <nsswitch.h> 89 90 #ifdef YP 91 #include <rpc/rpc.h> 92 #include <rpcsvc/yp_prot.h> 93 #include <rpcsvc/ypclnt.h> 94 #endif 95 96 #include "servent.h" 97 98 #ifndef RUMP_ACTION 99 #ifdef __weak_alias 100 __weak_alias(getaddrinfo,_getaddrinfo) 101 __weak_alias(allocaddrinfo,_allocaddrinfo) 102 __weak_alias(freeaddrinfo,_freeaddrinfo) 103 __weak_alias(gai_strerror,_gai_strerror) 104 #endif 105 #endif 106 107 #define SUCCESS 0 108 #define ANY 0 109 #define YES 1 110 #define NO 0 111 112 #define sa4addr(sa) ((void *)&((struct sockaddr_in *)(void *)sa)->sin_addr) 113 #define sa6addr(sa) ((void *)&((struct sockaddr_in6 *)(void *)sa)->sin6_addr) 114 115 static const char in_addrany[] = { 0, 0, 0, 0 }; 116 static const char in_loopback[] = { 127, 0, 0, 1 }; 117 #ifdef INET6 118 static const char in6_addrany[] = { 119 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 120 }; 121 static const char in6_loopback[] = { 122 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 123 }; 124 #endif 125 126 struct policyqueue { 127 TAILQ_ENTRY(policyqueue) pc_entry; 128 #ifdef INET6 129 struct in6_addrpolicy pc_policy; 130 #endif 131 }; 132 TAILQ_HEAD(policyhead, policyqueue); 133 134 static const struct afd { 135 int a_af; 136 int a_addrlen; 137 int a_socklen; 138 int a_off; 139 const char *a_addrany; 140 const char *a_loopback; 141 int a_scoped; 142 } afdl [] = { 143 #ifdef INET6 144 {PF_INET6, sizeof(struct in6_addr), 145 sizeof(struct sockaddr_in6), 146 offsetof(struct sockaddr_in6, sin6_addr), 147 in6_addrany, in6_loopback, 1}, 148 #endif 149 {PF_INET, sizeof(struct in_addr), 150 sizeof(struct sockaddr_in), 151 offsetof(struct sockaddr_in, sin_addr), 152 in_addrany, in_loopback, 0}, 153 {0, 0, 0, 0, NULL, NULL, 0}, 154 }; 155 156 struct explore { 157 int e_af; 158 int e_socktype; 159 int e_protocol; 160 const char *e_protostr; 161 int e_wild; 162 #define WILD_AF(ex) ((ex)->e_wild & 0x01) 163 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 164 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 165 }; 166 167 static const struct explore explore[] = { 168 #if 0 169 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 170 #endif 171 #ifdef INET6 172 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 173 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 174 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 175 #endif 176 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 177 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 178 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 179 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 180 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 181 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, 182 { -1, 0, 0, NULL, 0 }, 183 }; 184 185 #ifdef INET6 186 #define PTON_MAX 16 187 #else 188 #define PTON_MAX 4 189 #endif 190 191 #define AIO_SRCFLAG_DEPRECATED 0x1 192 193 struct ai_order { 194 union { 195 struct sockaddr_storage aiou_ss; 196 struct sockaddr aiou_sa; 197 } aio_src_un; 198 #define aio_srcsa aio_src_un.aiou_sa 199 uint32_t aio_srcflag; 200 int aio_srcscope; 201 int aio_dstscope; 202 struct policyqueue *aio_srcpolicy; 203 struct policyqueue *aio_dstpolicy; 204 struct addrinfo *aio_ai; 205 int aio_matchlen; 206 }; 207 208 static const ns_src default_dns_files[] = { 209 { NSSRC_FILES, NS_SUCCESS }, 210 { NSSRC_DNS, NS_SUCCESS }, 211 { 0, 0 } 212 }; 213 214 #define MAXPACKET (64*1024) 215 216 typedef union { 217 HEADER hdr; 218 u_char buf[MAXPACKET]; 219 } querybuf; 220 221 struct res_target { 222 struct res_target *next; 223 const char *name; /* domain name */ 224 int qclass, qtype; /* class and type of query */ 225 u_char *answer; /* buffer to put answer */ 226 int anslen; /* size of answer buffer */ 227 int n; /* result length */ 228 }; 229 230 struct srvinfo { 231 struct srvinfo *next; 232 char name[MAXDNAME]; 233 int port, pri, weight; 234 }; 235 236 static int gai_srvok(const char *); 237 static int str2number(const char *); 238 static int explore_fqdn(const struct addrinfo *, const char *, 239 const char *, struct addrinfo **, struct servent_data *); 240 static int explore_null(const struct addrinfo *, 241 const char *, struct addrinfo **, struct servent_data *); 242 static int explore_numeric(const struct addrinfo *, const char *, 243 const char *, struct addrinfo **, const char *, struct servent_data *); 244 static int explore_numeric_scope(const struct addrinfo *, const char *, 245 const char *, struct addrinfo **, struct servent_data *); 246 static int get_canonname(const struct addrinfo *, 247 struct addrinfo *, const char *); 248 static struct addrinfo *get_ai(const struct addrinfo *, 249 const struct afd *, const char *); 250 static int get_portmatch(const struct addrinfo *, const char *, 251 struct servent_data *); 252 static int get_port(const struct addrinfo *, const char *, int, 253 struct servent_data *); 254 static const struct afd *find_afd(int); 255 static int addrconfig(uint64_t *); 256 static void set_source(struct ai_order *, struct policyhead *, 257 struct servent_data *); 258 static int comp_dst(const void *, const void *); 259 #ifdef INET6 260 static int ip6_str2scopeid(const char *, struct sockaddr_in6 *, uint32_t *); 261 #endif 262 static int gai_addr2scopetype(struct sockaddr *); 263 264 static int reorder(struct addrinfo *, struct servent_data *); 265 static int get_addrselectpolicy(struct policyhead *); 266 static void free_addrselectpolicy(struct policyhead *); 267 static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 268 struct policyhead *); 269 static int matchlen(struct sockaddr *, struct sockaddr *); 270 271 static struct addrinfo *getanswer(res_state, const querybuf *, int, 272 const char *, int, const struct addrinfo *); 273 static void aisort(struct addrinfo *s, res_state res); 274 static struct addrinfo * _dns_query(struct res_target *, 275 const struct addrinfo *, res_state, int); 276 static struct addrinfo * _dns_srv_lookup(const char *, const char *, 277 const struct addrinfo *); 278 static struct addrinfo * _dns_host_lookup(const char *, 279 const struct addrinfo *); 280 static int _dns_getaddrinfo(void *, void *, va_list); 281 static void _sethtent(FILE **); 282 static void _endhtent(FILE **); 283 static struct addrinfo *_gethtent(FILE **, const char *, 284 const struct addrinfo *); 285 static int _files_getaddrinfo(void *, void *, va_list); 286 #ifdef YP 287 static struct addrinfo *_yphostent(char *, const struct addrinfo *); 288 static int _yp_getaddrinfo(void *, void *, va_list); 289 #endif 290 291 static int res_queryN(const char *, struct res_target *, res_state); 292 static int res_searchN(const char *, struct res_target *, res_state); 293 static int res_querydomainN(const char *, const char *, 294 struct res_target *, res_state); 295 296 static const char * const ai_errlist[] = { 297 "Success", 298 "Address family for hostname not supported", /* EAI_ADDRFAMILY */ 299 "Temporary failure in name resolution", /* EAI_AGAIN */ 300 "Invalid value for ai_flags", /* EAI_BADFLAGS */ 301 "Non-recoverable failure in name resolution", /* EAI_FAIL */ 302 "ai_family not supported", /* EAI_FAMILY */ 303 "Memory allocation failure", /* EAI_MEMORY */ 304 "No address associated with hostname", /* EAI_NODATA */ 305 "hostname or servname not provided or not known", /* EAI_NONAME */ 306 "servname not supported for ai_socktype", /* EAI_SERVICE */ 307 "ai_socktype not supported", /* EAI_SOCKTYPE */ 308 "System error returned in errno", /* EAI_SYSTEM */ 309 "Invalid value for hints", /* EAI_BADHINTS */ 310 "Resolved protocol is unknown", /* EAI_PROTOCOL */ 311 "Argument buffer overflow", /* EAI_OVERFLOW */ 312 "Unknown error", /* EAI_MAX */ 313 }; 314 315 /* XXX macros that make external reference is BAD. */ 316 317 #define GET_AI(ai, afd, addr) \ 318 do { \ 319 /* external reference: pai, error, and label free */ \ 320 (ai) = get_ai(pai, (afd), (addr)); \ 321 if ((ai) == NULL) { \ 322 error = EAI_MEMORY; \ 323 goto free; \ 324 } \ 325 } while (0) 326 327 #define GET_PORT(ai, serv, svd) \ 328 do { \ 329 /* external reference: error and label free */ \ 330 error = get_port((ai), (serv), 0, (svd)); \ 331 if (error != 0) \ 332 goto free; \ 333 } while (0) 334 335 #define GET_CANONNAME(ai, str) \ 336 do { \ 337 /* external reference: pai, error and label free */ \ 338 error = get_canonname(pai, (ai), (str)); \ 339 if (error != 0) \ 340 goto free; \ 341 } while (0) 342 343 #define ERR(err) \ 344 do { \ 345 /* external reference: error, and label bad */ \ 346 error = (err); \ 347 goto bad; \ 348 /*NOTREACHED*/ \ 349 } while (0) 350 351 #define MATCH_FAMILY(x, y, w) \ 352 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || \ 353 (y) == PF_UNSPEC))) 354 #define MATCH(x, y, w) \ 355 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 356 357 const char * 358 gai_strerror(int ecode) 359 { 360 if (ecode < 0 || ecode > EAI_MAX) 361 ecode = EAI_MAX; 362 return ai_errlist[ecode]; 363 } 364 365 void 366 freeaddrinfo(struct addrinfo *ai) 367 { 368 struct addrinfo *next; 369 370 _DIAGASSERT(ai != NULL); 371 372 do { 373 next = ai->ai_next; 374 if (ai->ai_canonname) 375 free(ai->ai_canonname); 376 /* no need to free(ai->ai_addr) */ 377 free(ai); 378 ai = next; 379 } while (ai); 380 } 381 382 /* 383 * We don't want localization to affect us 384 */ 385 #define PERIOD '.' 386 #define hyphenchar(c) ((c) == '-') 387 #define periodchar(c) ((c) == PERIOD) 388 #define underschar(c) ((c) == '_') 389 #define alphachar(c) (((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z')) 390 #define digitchar(c) ((c) >= '0' && (c) <= '9') 391 392 #define firstchar(c) (alphachar(c) || digitchar(c) || underschar(c)) 393 #define lastchar(c) (alphachar(c) || digitchar(c)) 394 #define middlechar(c) (lastchar(c) || hyphenchar(c)) 395 396 static int 397 gai_srvok(const char *dn) 398 { 399 int nch, pch, ch; 400 401 for (pch = PERIOD, nch = ch = *dn++; ch != '\0'; pch = ch, ch = nch) { 402 if (periodchar(ch)) 403 continue; 404 if (periodchar(pch)) { 405 if (!firstchar(ch)) 406 return 0; 407 } else if (periodchar(nch) || nch == '\0') { 408 if (!lastchar(ch)) 409 return 0; 410 } else if (!middlechar(ch)) 411 return 0; 412 } 413 return 1; 414 } 415 416 static in_port_t * 417 getport(struct addrinfo *ai) { 418 static in_port_t p; 419 420 switch (ai->ai_family) { 421 case AF_INET: 422 return &((struct sockaddr_in *)(void *)ai->ai_addr)->sin_port; 423 #ifdef INET6 424 case AF_INET6: 425 return &((struct sockaddr_in6 *)(void *)ai->ai_addr)->sin6_port; 426 #endif 427 default: 428 p = 0; 429 /* XXX: abort()? */ 430 return &p; 431 } 432 } 433 434 static int 435 str2number(const char *p) 436 { 437 char *ep; 438 unsigned long v; 439 440 _DIAGASSERT(p != NULL); 441 442 if (*p == '\0') 443 return -1; 444 ep = NULL; 445 errno = 0; 446 v = strtoul(p, &ep, 10); 447 if (errno == 0 && ep && *ep == '\0' && v <= INT_MAX) 448 return (int)v; 449 else 450 return -1; 451 } 452 453 int 454 getaddrinfo(const char *hostname, const char *servname, 455 const struct addrinfo *hints, struct addrinfo **res) 456 { 457 struct addrinfo sentinel; 458 struct addrinfo *cur; 459 int error = 0; 460 struct addrinfo ai; 461 struct addrinfo ai0; 462 struct addrinfo *pai; 463 const struct explore *ex; 464 struct servent_data svd; 465 uint64_t mask = (uint64_t)~0ULL; 466 int numeric = 0; 467 468 /* hostname is allowed to be NULL */ 469 /* servname is allowed to be NULL */ 470 /* hints is allowed to be NULL */ 471 _DIAGASSERT(res != NULL); 472 473 (void)memset(&svd, 0, sizeof(svd)); 474 memset(&sentinel, 0, sizeof(sentinel)); 475 cur = &sentinel; 476 memset(&ai, 0, sizeof(ai)); 477 pai = &ai; 478 pai->ai_flags = 0; 479 pai->ai_family = PF_UNSPEC; 480 pai->ai_socktype = ANY; 481 pai->ai_protocol = ANY; 482 pai->ai_addrlen = 0; 483 pai->ai_canonname = NULL; 484 pai->ai_addr = NULL; 485 pai->ai_next = NULL; 486 487 if (hostname == NULL && servname == NULL) 488 return EAI_NONAME; 489 if (hints) { 490 /* error check for hints */ 491 if (hints->ai_addrlen || hints->ai_canonname || 492 hints->ai_addr || hints->ai_next) 493 ERR(EAI_BADHINTS); /* xxx */ 494 if (hints->ai_flags & ~AI_MASK) 495 ERR(EAI_BADFLAGS); 496 switch (hints->ai_family) { 497 case PF_UNSPEC: 498 case PF_INET: 499 #ifdef INET6 500 case PF_INET6: 501 #endif 502 break; 503 default: 504 ERR(EAI_FAMILY); 505 } 506 memcpy(pai, hints, sizeof(*pai)); 507 508 /* 509 * if both socktype/protocol are specified, check if they 510 * are meaningful combination. 511 */ 512 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 513 for (ex = explore; ex->e_af >= 0; ex++) { 514 if (pai->ai_family != ex->e_af) 515 continue; 516 if (ex->e_socktype == ANY) 517 continue; 518 if (ex->e_protocol == ANY) 519 continue; 520 if (pai->ai_socktype == ex->e_socktype 521 && pai->ai_protocol != ex->e_protocol) { 522 ERR(EAI_BADHINTS); 523 } 524 } 525 } 526 } 527 528 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && addrconfig(&mask) == -1) 529 ERR(EAI_FAIL); 530 531 /* 532 * check for special cases. (1) numeric servname is disallowed if 533 * socktype/protocol are left unspecified. (2) servname is disallowed 534 * for raw and other inet{,6} sockets. 535 */ 536 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 537 #ifdef PF_INET6 538 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 539 #endif 540 ) { 541 ai0 = *pai; /* backup *pai */ 542 543 if (pai->ai_family == PF_UNSPEC) { 544 #ifdef PF_INET6 545 pai->ai_family = PF_INET6; 546 #else 547 pai->ai_family = PF_INET; 548 #endif 549 } 550 error = get_portmatch(pai, servname, &svd); 551 if (error) 552 goto bad; 553 554 *pai = ai0; 555 } 556 557 ai0 = *pai; 558 559 /* NULL hostname, or numeric hostname */ 560 for (ex = explore; ex->e_af >= 0; ex++) { 561 *pai = ai0; 562 563 /* ADDRCONFIG check */ 564 if ((((uint64_t)1 << ex->e_af) & mask) == 0) 565 continue; 566 567 /* PF_UNSPEC entries are prepared for DNS queries only */ 568 if (ex->e_af == PF_UNSPEC) 569 continue; 570 571 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 572 continue; 573 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 574 continue; 575 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 576 continue; 577 if (pai->ai_family == PF_UNSPEC) 578 pai->ai_family = ex->e_af; 579 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 580 pai->ai_socktype = ex->e_socktype; 581 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 582 pai->ai_protocol = ex->e_protocol; 583 584 if (hostname == NULL) 585 error = explore_null(pai, servname, &cur->ai_next, 586 &svd); 587 else 588 error = explore_numeric_scope(pai, hostname, servname, 589 &cur->ai_next, &svd); 590 591 if (error) 592 goto free; 593 594 while (cur->ai_next) 595 cur = cur->ai_next; 596 } 597 598 /* 599 * XXX 600 * If numeric representation of AF1 can be interpreted as FQDN 601 * representation of AF2, we need to think again about the code below. 602 */ 603 if (sentinel.ai_next) { 604 numeric = 1; 605 goto good; 606 } 607 608 if (hostname == NULL) 609 ERR(EAI_NODATA); 610 if (pai->ai_flags & AI_NUMERICHOST) 611 ERR(EAI_NONAME); 612 613 /* 614 * hostname as alphabetical name. 615 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 616 * outer loop by AFs. 617 */ 618 for (ex = explore; ex->e_af >= 0; ex++) { 619 *pai = ai0; 620 621 622 /* ADDRCONFIG check */ 623 /* PF_UNSPEC entries are prepared for DNS queries only */ 624 if (ex->e_af != PF_UNSPEC && 625 (((uint64_t)1 << ex->e_af) & mask) == 0) 626 continue; 627 628 /* require exact match for family field */ 629 if (pai->ai_family != ex->e_af) 630 continue; 631 632 if (!MATCH(pai->ai_socktype, ex->e_socktype, 633 WILD_SOCKTYPE(ex))) { 634 continue; 635 } 636 if (!MATCH(pai->ai_protocol, ex->e_protocol, 637 WILD_PROTOCOL(ex))) { 638 continue; 639 } 640 641 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 642 pai->ai_socktype = ex->e_socktype; 643 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 644 pai->ai_protocol = ex->e_protocol; 645 646 error = explore_fqdn(pai, hostname, servname, &cur->ai_next, 647 &svd); 648 649 while (cur && cur->ai_next) 650 cur = cur->ai_next; 651 } 652 653 /* XXX */ 654 if (sentinel.ai_next) 655 error = 0; 656 657 if (error) 658 goto free; 659 660 if (sentinel.ai_next) { 661 good: 662 /* 663 * If the returned entry is for an active connection, 664 * and the given name is not numeric, reorder the 665 * list, so that the application would try the list 666 * in the most efficient order. Since the head entry 667 * of the original list may contain ai_canonname and 668 * that entry may be moved elsewhere in the new list, 669 * we keep the pointer and will restore it in the new 670 * head entry. (Note that RFC3493 requires the head 671 * entry store it when requested by the caller). 672 */ 673 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 674 if (!numeric) { 675 char *canonname; 676 677 canonname = sentinel.ai_next->ai_canonname; 678 sentinel.ai_next->ai_canonname = NULL; 679 (void)reorder(&sentinel, &svd); 680 if (sentinel.ai_next->ai_canonname == NULL) { 681 sentinel.ai_next->ai_canonname 682 = canonname; 683 } else if (canonname != NULL) 684 free(canonname); 685 } 686 } 687 endservent_r(&svd); 688 *res = sentinel.ai_next; 689 return SUCCESS; 690 } else 691 error = EAI_FAIL; 692 free: 693 bad: 694 endservent_r(&svd); 695 if (sentinel.ai_next) 696 freeaddrinfo(sentinel.ai_next); 697 *res = NULL; 698 return error; 699 } 700 701 static int 702 reorder(struct addrinfo *sentinel, struct servent_data *svd) 703 { 704 struct addrinfo *ai, **aip; 705 struct ai_order *aio; 706 int i, n; 707 struct policyhead policyhead; 708 709 /* count the number of addrinfo elements for sorting. */ 710 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 711 ; 712 713 /* 714 * If the number is small enough, we can skip the reordering process. 715 */ 716 if (n <= 1) 717 return n; 718 719 /* allocate a temporary array for sort and initialization of it. */ 720 if ((aio = calloc(n, sizeof(*aio))) == NULL) 721 return n; /* give up reordering */ 722 723 /* retrieve address selection policy from the kernel */ 724 TAILQ_INIT(&policyhead); 725 if (!get_addrselectpolicy(&policyhead)) { 726 /* no policy is installed into kernel, we don't sort. */ 727 free(aio); 728 return n; 729 } 730 731 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 732 aio[i].aio_ai = ai; 733 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 734 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 735 &policyhead); 736 set_source(&aio[i], &policyhead, svd); 737 } 738 739 /* perform sorting. */ 740 qsort(aio, n, sizeof(*aio), comp_dst); 741 742 /* reorder the addrinfo chain. */ 743 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 744 *aip = aio[i].aio_ai; 745 aip = &aio[i].aio_ai->ai_next; 746 } 747 *aip = NULL; 748 749 /* cleanup and return */ 750 free(aio); 751 free_addrselectpolicy(&policyhead); 752 return n; 753 } 754 755 static int 756 get_addrselectpolicy(struct policyhead *head) 757 { 758 #ifdef INET6 759 static const int mib[] = { 760 CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 761 static const u_int miblen = (u_int)__arraycount(mib); 762 size_t l; 763 char *buf; 764 struct in6_addrpolicy *pol, *ep; 765 766 if (sysctl(mib, miblen, NULL, &l, NULL, 0) < 0) 767 return 0; 768 if (l == 0) 769 return 0; 770 if ((buf = malloc(l)) == NULL) 771 return 0; 772 if (sysctl(mib, miblen, buf, &l, NULL, 0) < 0) { 773 free(buf); 774 return 0; 775 } 776 777 ep = (void *)(buf + l); 778 for (pol = (void *)buf; pol + 1 <= ep; pol++) { 779 struct policyqueue *new; 780 781 if ((new = malloc(sizeof(*new))) == NULL) { 782 free_addrselectpolicy(head); /* make the list empty */ 783 break; 784 } 785 new->pc_policy = *pol; 786 TAILQ_INSERT_TAIL(head, new, pc_entry); 787 } 788 789 free(buf); 790 return 1; 791 #else 792 return 0; 793 #endif 794 } 795 796 static void 797 free_addrselectpolicy(struct policyhead *head) 798 { 799 struct policyqueue *ent, *nent; 800 801 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 802 nent = TAILQ_NEXT(ent, pc_entry); 803 TAILQ_REMOVE(head, ent, pc_entry); 804 free(ent); 805 } 806 } 807 808 static struct policyqueue * 809 match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 810 { 811 #ifdef INET6 812 struct policyqueue *ent, *bestent = NULL; 813 struct in6_addrpolicy *pol; 814 int curmatchlen, bestmatchlen = -1; 815 u_char *mp, *ep, *k, *p; 816 u_int m; 817 struct sockaddr_in6 key; 818 819 switch(addr->sa_family) { 820 case AF_INET6: 821 memcpy(&key, addr, sizeof(key)); 822 break; 823 case AF_INET: 824 /* convert the address into IPv4-mapped IPv6 address. */ 825 memset(&key, 0, sizeof(key)); 826 key.sin6_family = AF_INET6; 827 key.sin6_len = sizeof(key); 828 key.sin6_addr.s6_addr[10] = 0xff; 829 key.sin6_addr.s6_addr[11] = 0xff; 830 memcpy(&key.sin6_addr.s6_addr[12], sa4addr(addr), 4); 831 break; 832 default: 833 return NULL; 834 } 835 836 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 837 pol = &ent->pc_policy; 838 curmatchlen = 0; 839 840 mp = (void *)&pol->addrmask.sin6_addr; 841 ep = mp + 16; /* XXX: scope field? */ 842 k = (void *)&key.sin6_addr; 843 p = (void *)&pol->addr.sin6_addr; 844 for (; mp < ep && *mp; mp++, k++, p++) { 845 m = *mp; 846 if ((*k & m) != *p) 847 goto next; /* not match */ 848 if (m == 0xff) /* short cut for a typical case */ 849 curmatchlen += 8; 850 else { 851 while (m >= 0x80) { 852 curmatchlen++; 853 m <<= 1; 854 } 855 } 856 } 857 858 /* matched. check if this is better than the current best. */ 859 if (curmatchlen > bestmatchlen) { 860 bestent = ent; 861 bestmatchlen = curmatchlen; 862 } 863 864 next: 865 continue; 866 } 867 868 return bestent; 869 #else 870 return NULL; 871 #endif 872 873 } 874 875 static void 876 set_source(struct ai_order *aio, struct policyhead *ph, 877 struct servent_data *svd) 878 { 879 struct addrinfo ai = *aio->aio_ai; 880 struct sockaddr_storage ss; 881 socklen_t srclen; 882 int s; 883 884 /* set unspec ("no source is available"), just in case */ 885 aio->aio_srcsa.sa_family = AF_UNSPEC; 886 aio->aio_srcscope = -1; 887 888 switch(ai.ai_family) { 889 case AF_INET: 890 #ifdef INET6 891 case AF_INET6: 892 #endif 893 break; 894 default: /* ignore unsupported AFs explicitly */ 895 return; 896 } 897 898 /* XXX: make a dummy addrinfo to call connect() */ 899 ai.ai_socktype = SOCK_DGRAM; 900 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 901 ai.ai_next = NULL; 902 memset(&ss, 0, sizeof(ss)); 903 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 904 ai.ai_addr = (void *)&ss; 905 get_port(&ai, "1", 0, svd); 906 907 /* open a socket to get the source address for the given dst */ 908 if ((s = socket(ai.ai_family, ai.ai_socktype | SOCK_CLOEXEC, 909 ai.ai_protocol)) < 0) 910 return; /* give up */ 911 if (connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 912 goto cleanup; 913 srclen = ai.ai_addrlen; 914 if (getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 915 aio->aio_srcsa.sa_family = AF_UNSPEC; 916 goto cleanup; 917 } 918 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 919 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 920 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 921 #ifdef INET6 922 if (ai.ai_family == AF_INET6) { 923 struct in6_ifreq ifr6; 924 uint32_t flags6; 925 926 memset(&ifr6, 0, sizeof(ifr6)); 927 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 928 if (ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 929 flags6 = ifr6.ifr_ifru.ifru_flags6; 930 if ((flags6 & IN6_IFF_DEPRECATED)) 931 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 932 } 933 } 934 #endif 935 936 cleanup: 937 close(s); 938 return; 939 } 940 941 static int 942 matchlen(struct sockaddr *src, struct sockaddr *dst) 943 { 944 int match = 0; 945 u_char *s, *d; 946 u_char *lim; 947 u_int r, addrlen; 948 949 switch (src->sa_family) { 950 #ifdef INET6 951 case AF_INET6: 952 s = sa6addr(src); 953 d = sa6addr(dst); 954 addrlen = sizeof(struct in6_addr); 955 lim = s + addrlen; 956 break; 957 #endif 958 case AF_INET: 959 s = sa4addr(src); 960 d = sa4addr(dst); 961 addrlen = sizeof(struct in_addr); 962 lim = s + addrlen; 963 break; 964 default: 965 return 0; 966 } 967 968 while (s < lim) 969 if ((r = (*d++ ^ *s++)) != 0) { 970 while (r < addrlen * 8) { 971 match++; 972 r <<= 1; 973 } 974 break; 975 } else 976 match += 8; 977 return match; 978 } 979 980 static int 981 comp_dst(const void *arg1, const void *arg2) 982 { 983 const struct ai_order *dst1 = arg1, *dst2 = arg2; 984 985 /* 986 * Rule 1: Avoid unusable destinations. 987 * XXX: we currently do not consider if an appropriate route exists. 988 */ 989 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 990 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 991 return -1; 992 } 993 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 994 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 995 return 1; 996 } 997 998 /* Rule 2: Prefer matching scope. */ 999 if (dst1->aio_dstscope == dst1->aio_srcscope && 1000 dst2->aio_dstscope != dst2->aio_srcscope) { 1001 return -1; 1002 } 1003 if (dst1->aio_dstscope != dst1->aio_srcscope && 1004 dst2->aio_dstscope == dst2->aio_srcscope) { 1005 return 1; 1006 } 1007 1008 /* Rule 3: Avoid deprecated addresses. */ 1009 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 1010 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 1011 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 1012 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 1013 return -1; 1014 } 1015 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 1016 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 1017 return 1; 1018 } 1019 } 1020 1021 /* Rule 4: Prefer home addresses. */ 1022 /* XXX: not implemented yet */ 1023 1024 /* Rule 5: Prefer matching label. */ 1025 #ifdef INET6 1026 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 1027 dst1->aio_srcpolicy->pc_policy.label == 1028 dst1->aio_dstpolicy->pc_policy.label && 1029 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 1030 dst2->aio_srcpolicy->pc_policy.label != 1031 dst2->aio_dstpolicy->pc_policy.label)) { 1032 return -1; 1033 } 1034 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 1035 dst2->aio_srcpolicy->pc_policy.label == 1036 dst2->aio_dstpolicy->pc_policy.label && 1037 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 1038 dst1->aio_srcpolicy->pc_policy.label != 1039 dst1->aio_dstpolicy->pc_policy.label)) { 1040 return 1; 1041 } 1042 #endif 1043 1044 /* Rule 6: Prefer higher precedence. */ 1045 #ifdef INET6 1046 if (dst1->aio_dstpolicy && 1047 (dst2->aio_dstpolicy == NULL || 1048 dst1->aio_dstpolicy->pc_policy.preced > 1049 dst2->aio_dstpolicy->pc_policy.preced)) { 1050 return -1; 1051 } 1052 if (dst2->aio_dstpolicy && 1053 (dst1->aio_dstpolicy == NULL || 1054 dst2->aio_dstpolicy->pc_policy.preced > 1055 dst1->aio_dstpolicy->pc_policy.preced)) { 1056 return 1; 1057 } 1058 #endif 1059 1060 /* Rule 7: Prefer native transport. */ 1061 /* XXX: not implemented yet */ 1062 1063 /* Rule 8: Prefer smaller scope. */ 1064 if (dst1->aio_dstscope >= 0 && 1065 dst1->aio_dstscope < dst2->aio_dstscope) { 1066 return -1; 1067 } 1068 if (dst2->aio_dstscope >= 0 && 1069 dst2->aio_dstscope < dst1->aio_dstscope) { 1070 return 1; 1071 } 1072 1073 /* 1074 * Rule 9: Use longest matching prefix. 1075 * We compare the match length in a same AF only. 1076 */ 1077 if (dst1->aio_ai->ai_addr->sa_family == 1078 dst2->aio_ai->ai_addr->sa_family && 1079 dst1->aio_ai->ai_addr->sa_family != AF_INET) { 1080 if (dst1->aio_matchlen > dst2->aio_matchlen) { 1081 return -1; 1082 } 1083 if (dst1->aio_matchlen < dst2->aio_matchlen) { 1084 return 1; 1085 } 1086 } 1087 1088 /* Rule 10: Otherwise, leave the order unchanged. */ 1089 return -1; 1090 } 1091 1092 /* 1093 * Copy from scope.c. 1094 * XXX: we should standardize the functions and link them as standard 1095 * library. 1096 */ 1097 static int 1098 gai_addr2scopetype(struct sockaddr *sa) 1099 { 1100 #ifdef INET6 1101 struct sockaddr_in6 *sa6; 1102 #endif 1103 struct sockaddr_in *sa4; 1104 u_char *p; 1105 1106 switch(sa->sa_family) { 1107 #ifdef INET6 1108 case AF_INET6: 1109 sa6 = (void *)sa; 1110 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1111 /* just use the scope field of the multicast address */ 1112 return sa6->sin6_addr.s6_addr[2] & 0x0f; 1113 } 1114 /* 1115 * Unicast addresses: map scope type to corresponding scope 1116 * value defined for multcast addresses. 1117 * XXX: hardcoded scope type values are bad... 1118 */ 1119 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1120 return 1; /* node local scope */ 1121 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1122 return 2; /* link-local scope */ 1123 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1124 return 5; /* site-local scope */ 1125 return 14; /* global scope */ 1126 #endif 1127 case AF_INET: 1128 /* 1129 * IPv4 pseudo scoping according to RFC 3484. 1130 */ 1131 sa4 = (void *)sa; 1132 p = (u_char *)(void *)&sa4->sin_addr; 1133 /* IPv4 autoconfiguration addresses have link-local scope. */ 1134 if (p[0] == 169 && p[1] == 254) 1135 return 2; 1136 /* Private addresses have site-local scope. */ 1137 if (p[0] == 10 || 1138 (p[0] == 172 && (p[1] & 0xf0) == 16) || 1139 (p[0] == 192 && p[1] == 168)) 1140 return 14; /* XXX: It should be 5 unless NAT */ 1141 /* Loopback addresses have link-local scope. */ 1142 if (p[0] == 127) 1143 return 2; 1144 return 14; 1145 default: 1146 errno = EAFNOSUPPORT; /* is this a good error? */ 1147 return -1; 1148 } 1149 } 1150 1151 /* 1152 * FQDN hostname, DNS lookup 1153 */ 1154 static int 1155 explore_fqdn(const struct addrinfo *pai, const char *hostname, 1156 const char *servname, struct addrinfo **res, struct servent_data *svd) 1157 { 1158 struct addrinfo *result; 1159 struct addrinfo *cur; 1160 int error = 0; 1161 static const ns_dtab dtab[] = { 1162 NS_FILES_CB(_files_getaddrinfo, NULL) 1163 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1164 NS_NIS_CB(_yp_getaddrinfo, NULL) 1165 NS_NULL_CB 1166 }; 1167 1168 _DIAGASSERT(pai != NULL); 1169 /* hostname may be NULL */ 1170 /* servname may be NULL */ 1171 _DIAGASSERT(res != NULL); 1172 1173 result = NULL; 1174 1175 /* 1176 * if the servname does not match socktype/protocol, ignore it. 1177 */ 1178 if (get_portmatch(pai, servname, svd) != 0) 1179 return 0; 1180 1181 switch (nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1182 default_dns_files, hostname, pai, servname)) { 1183 case NS_TRYAGAIN: 1184 error = EAI_AGAIN; 1185 goto free; 1186 case NS_UNAVAIL: 1187 error = EAI_FAIL; 1188 goto free; 1189 case NS_NOTFOUND: 1190 error = EAI_NODATA; 1191 goto free; 1192 case NS_SUCCESS: 1193 error = 0; 1194 for (cur = result; cur; cur = cur->ai_next) { 1195 /* Check for already filled port. */ 1196 if (*getport(cur)) 1197 continue; 1198 GET_PORT(cur, servname, svd); 1199 /* canonname should be filled already */ 1200 } 1201 break; 1202 } 1203 1204 *res = result; 1205 1206 return 0; 1207 1208 free: 1209 if (result) 1210 freeaddrinfo(result); 1211 return error; 1212 } 1213 1214 /* 1215 * hostname == NULL. 1216 * passive socket -> anyaddr (0.0.0.0 or ::) 1217 * non-passive socket -> localhost (127.0.0.1 or ::1) 1218 */ 1219 static int 1220 explore_null(const struct addrinfo *pai, const char *servname, 1221 struct addrinfo **res, struct servent_data *svd) 1222 { 1223 int s; 1224 const struct afd *afd; 1225 struct addrinfo *cur; 1226 struct addrinfo sentinel; 1227 int error; 1228 1229 _DIAGASSERT(pai != NULL); 1230 /* servname may be NULL */ 1231 _DIAGASSERT(res != NULL); 1232 1233 *res = NULL; 1234 sentinel.ai_next = NULL; 1235 cur = &sentinel; 1236 1237 /* 1238 * filter out AFs that are not supported by the kernel 1239 * XXX errno? 1240 */ 1241 s = socket(pai->ai_family, SOCK_DGRAM, 0); 1242 if (s < 0) { 1243 if (errno != EMFILE) 1244 return 0; 1245 } else 1246 close(s); 1247 1248 /* 1249 * if the servname does not match socktype/protocol, ignore it. 1250 */ 1251 if (get_portmatch(pai, servname, svd) != 0) 1252 return 0; 1253 1254 afd = find_afd(pai->ai_family); 1255 if (afd == NULL) 1256 return 0; 1257 1258 if (pai->ai_flags & AI_PASSIVE) { 1259 GET_AI(cur->ai_next, afd, afd->a_addrany); 1260 /* xxx meaningless? 1261 * GET_CANONNAME(cur->ai_next, "anyaddr"); 1262 */ 1263 GET_PORT(cur->ai_next, servname, svd); 1264 } else { 1265 GET_AI(cur->ai_next, afd, afd->a_loopback); 1266 /* xxx meaningless? 1267 * GET_CANONNAME(cur->ai_next, "localhost"); 1268 */ 1269 GET_PORT(cur->ai_next, servname, svd); 1270 } 1271 cur = cur->ai_next; 1272 1273 *res = sentinel.ai_next; 1274 return 0; 1275 1276 free: 1277 if (sentinel.ai_next) 1278 freeaddrinfo(sentinel.ai_next); 1279 return error; 1280 } 1281 1282 /* 1283 * numeric hostname 1284 */ 1285 static int 1286 explore_numeric(const struct addrinfo *pai, const char *hostname, 1287 const char *servname, struct addrinfo **res, const char *canonname, 1288 struct servent_data *svd) 1289 { 1290 const struct afd *afd; 1291 struct addrinfo *cur; 1292 struct addrinfo sentinel; 1293 int error; 1294 char pton[PTON_MAX]; 1295 1296 _DIAGASSERT(pai != NULL); 1297 /* hostname may be NULL */ 1298 /* servname may be NULL */ 1299 _DIAGASSERT(res != NULL); 1300 1301 *res = NULL; 1302 sentinel.ai_next = NULL; 1303 cur = &sentinel; 1304 1305 /* 1306 * if the servname does not match socktype/protocol, ignore it. 1307 */ 1308 if (get_portmatch(pai, servname, svd) != 0) 1309 return 0; 1310 1311 afd = find_afd(pai->ai_family); 1312 if (afd == NULL) 1313 return 0; 1314 1315 switch (afd->a_af) { 1316 case AF_INET: 1317 /* 1318 * RFC3493 section 6.1, requires getaddrinfo() to accept 1319 * AF_INET formats that are accepted by inet_addr(); here 1320 * we use the equivalent inet_aton() function so we can 1321 * check for errors. inet_pton() only accepts addresses 1322 * in the dotted quad format and only in base 10, so we 1323 * need to treat AF_INET specially. 1324 * 1325 * We also check for trailing characters and fail if there 1326 * are any. This matches the inet_pton6(), but not the 1327 * inet_pton4() behavior. We choose to make the protocol 1328 * behavior consistent. 1329 */ 1330 if (inet_aton(hostname, (void *)pton) == 1 && 1331 hostname[strspn(hostname, "0123456789.xabcdefXABCDEF")] 1332 == '\0') { 1333 if (pai->ai_family == afd->a_af || 1334 pai->ai_family == PF_UNSPEC /*?*/) { 1335 GET_AI(cur->ai_next, afd, pton); 1336 GET_PORT(cur->ai_next, servname, svd); 1337 if ((pai->ai_flags & AI_CANONNAME)) { 1338 /* 1339 * Set the numeric address itself as 1340 * the canonical name, based on a 1341 * clarification in rfc2553bis-03. 1342 */ 1343 GET_CANONNAME(cur->ai_next, canonname); 1344 } 1345 while (cur && cur->ai_next) 1346 cur = cur->ai_next; 1347 } else 1348 ERR(EAI_FAMILY); /*xxx*/ 1349 } 1350 break; 1351 default: 1352 if (inet_pton(afd->a_af, hostname, pton) == 1) { 1353 if (pai->ai_family == afd->a_af || 1354 pai->ai_family == PF_UNSPEC /*?*/) { 1355 GET_AI(cur->ai_next, afd, pton); 1356 GET_PORT(cur->ai_next, servname, svd); 1357 if ((pai->ai_flags & AI_CANONNAME)) { 1358 /* 1359 * Set the numeric address itself as 1360 * the canonical name, based on a 1361 * clarification in rfc2553bis-03. 1362 */ 1363 GET_CANONNAME(cur->ai_next, canonname); 1364 } 1365 while (cur->ai_next) 1366 cur = cur->ai_next; 1367 } else 1368 ERR(EAI_FAMILY); /*xxx*/ 1369 } 1370 break; 1371 } 1372 1373 *res = sentinel.ai_next; 1374 return 0; 1375 1376 free: 1377 bad: 1378 if (sentinel.ai_next) 1379 freeaddrinfo(sentinel.ai_next); 1380 return error; 1381 } 1382 1383 /* 1384 * numeric hostname with scope 1385 */ 1386 static int 1387 explore_numeric_scope(const struct addrinfo *pai, const char *hostname, 1388 const char *servname, struct addrinfo **res, struct servent_data *svd) 1389 { 1390 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 1391 return explore_numeric(pai, hostname, servname, res, hostname, svd); 1392 #else 1393 const struct afd *afd; 1394 struct addrinfo *cur; 1395 int error; 1396 char *hostname2 = NULL, *addr; 1397 const char *cp, *scope; 1398 struct sockaddr_in6 *sin6; 1399 1400 _DIAGASSERT(pai != NULL); 1401 /* hostname may be NULL */ 1402 /* servname may be NULL */ 1403 _DIAGASSERT(res != NULL); 1404 1405 /* 1406 * if the servname does not match socktype/protocol, ignore it. 1407 */ 1408 if (get_portmatch(pai, servname, svd) != 0) 1409 return 0; 1410 1411 afd = find_afd(pai->ai_family); 1412 if (afd == NULL) 1413 return 0; 1414 1415 if (!afd->a_scoped) 1416 return explore_numeric(pai, hostname, servname, res, hostname, 1417 svd); 1418 1419 cp = strchr(hostname, SCOPE_DELIMITER); 1420 if (cp == NULL) 1421 return explore_numeric(pai, hostname, servname, res, hostname, 1422 svd); 1423 1424 /* 1425 * Handle special case of <scoped_address><delimiter><scope id> 1426 */ 1427 hostname2 = strdup(hostname); 1428 if (hostname2 == NULL) 1429 return EAI_MEMORY; 1430 /* terminate at the delimiter */ 1431 hostname2[cp - hostname] = '\0'; 1432 addr = hostname2; 1433 scope = cp + 1; 1434 1435 error = explore_numeric(pai, addr, servname, res, hostname, svd); 1436 if (error == 0) { 1437 uint32_t scopeid; 1438 1439 for (cur = *res; cur; cur = cur->ai_next) { 1440 if (cur->ai_family != AF_INET6) 1441 continue; 1442 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1443 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1444 free(hostname2); 1445 return EAI_NODATA; /* XXX: is return OK? */ 1446 } 1447 sin6->sin6_scope_id = scopeid; 1448 } 1449 } 1450 1451 free(hostname2); 1452 1453 return error; 1454 #endif 1455 } 1456 1457 static int 1458 get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) 1459 { 1460 1461 _DIAGASSERT(pai != NULL); 1462 _DIAGASSERT(ai != NULL); 1463 _DIAGASSERT(str != NULL); 1464 1465 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1466 ai->ai_canonname = strdup(str); 1467 if (ai->ai_canonname == NULL) 1468 return EAI_MEMORY; 1469 } 1470 return 0; 1471 } 1472 1473 struct addrinfo * 1474 allocaddrinfo(socklen_t addrlen) 1475 { 1476 struct addrinfo *ai; 1477 1478 ai = calloc(sizeof(struct addrinfo) + addrlen, 1); 1479 if (ai) { 1480 ai->ai_addr = (void *)(ai+1); 1481 ai->ai_addrlen = ai->ai_addr->sa_len = addrlen; 1482 } 1483 1484 return ai; 1485 } 1486 1487 static struct addrinfo * 1488 get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) 1489 { 1490 char *p; 1491 struct addrinfo *ai; 1492 struct sockaddr *save; 1493 1494 _DIAGASSERT(pai != NULL); 1495 _DIAGASSERT(afd != NULL); 1496 _DIAGASSERT(addr != NULL); 1497 1498 ai = allocaddrinfo((socklen_t)afd->a_socklen); 1499 if (ai == NULL) 1500 return NULL; 1501 1502 save = ai->ai_addr; 1503 memcpy(ai, pai, sizeof(struct addrinfo)); 1504 1505 /* since we just overwrote all of ai, we have 1506 to restore ai_addr and ai_addrlen */ 1507 ai->ai_addr = save; 1508 ai->ai_addrlen = (socklen_t)afd->a_socklen; 1509 1510 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1511 p = (char *)(void *)(ai->ai_addr); 1512 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1513 return ai; 1514 } 1515 1516 static int 1517 get_portmatch(const struct addrinfo *ai, const char *servname, 1518 struct servent_data *svd) 1519 { 1520 1521 _DIAGASSERT(ai != NULL); 1522 /* servname may be NULL */ 1523 1524 return get_port(ai, servname, 1, svd); 1525 } 1526 1527 static int 1528 get_port(const struct addrinfo *ai, const char *servname, int matchonly, 1529 struct servent_data *svd) 1530 { 1531 const char *proto; 1532 struct servent *sp; 1533 int port; 1534 int allownumeric; 1535 1536 _DIAGASSERT(ai != NULL); 1537 /* servname may be NULL */ 1538 1539 if (servname == NULL) 1540 return 0; 1541 switch (ai->ai_family) { 1542 case AF_INET: 1543 #ifdef AF_INET6 1544 case AF_INET6: 1545 #endif 1546 break; 1547 default: 1548 return 0; 1549 } 1550 1551 switch (ai->ai_socktype) { 1552 case SOCK_RAW: 1553 return EAI_SERVICE; 1554 case SOCK_DGRAM: 1555 case SOCK_STREAM: 1556 allownumeric = 1; 1557 break; 1558 case ANY: 1559 /* 1560 * This was 0. It is now 1 so that queries specifying 1561 * a NULL hint, or hint without socktype (but, hopefully, 1562 * with protocol) and numeric address actually work. 1563 */ 1564 allownumeric = 1; 1565 break; 1566 default: 1567 return EAI_SOCKTYPE; 1568 } 1569 1570 port = str2number(servname); 1571 if (port >= 0) { 1572 if (!allownumeric) 1573 return EAI_SERVICE; 1574 if (port < 0 || port > 65535) 1575 return EAI_SERVICE; 1576 port = htons(port); 1577 } else { 1578 struct servent sv; 1579 if (ai->ai_flags & AI_NUMERICSERV) 1580 return EAI_NONAME; 1581 1582 switch (ai->ai_socktype) { 1583 case SOCK_DGRAM: 1584 proto = "udp"; 1585 break; 1586 case SOCK_STREAM: 1587 proto = "tcp"; 1588 break; 1589 default: 1590 proto = NULL; 1591 break; 1592 } 1593 1594 sp = getservbyname_r(servname, proto, &sv, svd); 1595 if (sp == NULL) 1596 return EAI_SERVICE; 1597 port = sp->s_port; 1598 } 1599 1600 if (!matchonly) 1601 *getport(__UNCONST(ai)) = port; 1602 return 0; 1603 } 1604 1605 static const struct afd * 1606 find_afd(int af) 1607 { 1608 const struct afd *afd; 1609 1610 if (af == PF_UNSPEC) 1611 return NULL; 1612 for (afd = afdl; afd->a_af; afd++) { 1613 if (afd->a_af == af) 1614 return afd; 1615 } 1616 return NULL; 1617 } 1618 1619 /* 1620 * AI_ADDRCONFIG check: Build a mask containing a bit set for each address 1621 * family configured in the system. 1622 * 1623 */ 1624 static int 1625 addrconfig(uint64_t *mask) 1626 { 1627 struct ifaddrs *ifaddrs, *ifa; 1628 1629 if (getifaddrs(&ifaddrs) == -1) 1630 return -1; 1631 1632 *mask = 0; 1633 for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) 1634 if (ifa->ifa_addr && (ifa->ifa_flags & IFF_UP)) { 1635 _DIAGASSERT(ifa->ifa_addr->sa_family < 64); 1636 *mask |= (uint64_t)1 << ifa->ifa_addr->sa_family; 1637 } 1638 1639 freeifaddrs(ifaddrs); 1640 return 0; 1641 } 1642 1643 #ifdef INET6 1644 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1645 static int 1646 ip6_str2scopeid(const char *scope, struct sockaddr_in6 *sin6, uint32_t *scopeid) 1647 { 1648 u_long lscopeid; 1649 struct in6_addr *a6; 1650 char *ep; 1651 1652 _DIAGASSERT(scope != NULL); 1653 _DIAGASSERT(sin6 != NULL); 1654 _DIAGASSERT(scopeid != NULL); 1655 1656 a6 = &sin6->sin6_addr; 1657 1658 /* empty scopeid portion is invalid */ 1659 if (*scope == '\0') 1660 return -1; 1661 1662 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1663 /* 1664 * We currently assume a one-to-one mapping between links 1665 * and interfaces, so we simply use interface indices for 1666 * like-local scopes. 1667 */ 1668 *scopeid = if_nametoindex(scope); 1669 if (*scopeid == 0) 1670 goto trynumeric; 1671 return 0; 1672 } 1673 1674 /* still unclear about literal, allow numeric only - placeholder */ 1675 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1676 goto trynumeric; 1677 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1678 goto trynumeric; 1679 else 1680 goto trynumeric; /* global */ 1681 1682 /* try to convert to a numeric id as a last resort */ 1683 trynumeric: 1684 errno = 0; 1685 lscopeid = strtoul(scope, &ep, 10); 1686 *scopeid = (uint32_t)(lscopeid & 0xffffffffUL); 1687 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1688 return 0; 1689 else 1690 return -1; 1691 } 1692 #endif 1693 1694 /* code duplicate with gethnamaddr.c */ 1695 1696 static const char AskedForGot[] = 1697 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1698 1699 #define maybe_ok(res, nm, ok) (((res)->options & RES_NOCHECKNAME) != 0U || \ 1700 (ok)(nm) != 0) 1701 static struct addrinfo * 1702 getanswer(res_state res, const querybuf *answer, int anslen, const char *qname, 1703 int qtype, const struct addrinfo *pai) 1704 { 1705 struct addrinfo sentinel, *cur; 1706 struct addrinfo ai, *aip; 1707 const struct afd *afd; 1708 char *canonname; 1709 const HEADER *hp; 1710 const u_char *cp; 1711 int n; 1712 const u_char *eom; 1713 char *bp, *ep; 1714 int type, class, ancount, qdcount; 1715 int haveanswer, had_error; 1716 char tbuf[MAXDNAME]; 1717 int (*name_ok) (const char *); 1718 char hostbuf[8*1024]; 1719 int port, pri, weight; 1720 struct srvinfo *srvlist, *srv, *csrv; 1721 1722 _DIAGASSERT(answer != NULL); 1723 _DIAGASSERT(qname != NULL); 1724 _DIAGASSERT(pai != NULL); 1725 _DIAGASSERT(res != NULL); 1726 1727 memset(&sentinel, 0, sizeof(sentinel)); 1728 cur = &sentinel; 1729 1730 canonname = NULL; 1731 eom = answer->buf + anslen; 1732 switch (qtype) { 1733 case T_A: 1734 case T_AAAA: 1735 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1736 name_ok = res_hnok; 1737 break; 1738 case T_SRV: 1739 name_ok = gai_srvok; 1740 break; 1741 default: 1742 return NULL; /* XXX should be abort(); */ 1743 } 1744 /* 1745 * find first satisfactory answer 1746 */ 1747 hp = &answer->hdr; 1748 ancount = ntohs(hp->ancount); 1749 qdcount = ntohs(hp->qdcount); 1750 bp = hostbuf; 1751 ep = hostbuf + sizeof hostbuf; 1752 cp = answer->buf + HFIXEDSZ; 1753 if (qdcount != 1) { 1754 h_errno = NO_RECOVERY; 1755 return NULL; 1756 } 1757 n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp)); 1758 if ((n < 0) || !maybe_ok(res, bp, name_ok)) { 1759 h_errno = NO_RECOVERY; 1760 return NULL; 1761 } 1762 cp += n + QFIXEDSZ; 1763 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1764 /* res_send() has already verified that the query name is the 1765 * same as the one we sent; this just gets the expanded name 1766 * (i.e., with the succeeding search-domain tacked on). 1767 */ 1768 n = (int)strlen(bp) + 1; /* for the \0 */ 1769 if (n >= MAXHOSTNAMELEN) { 1770 h_errno = NO_RECOVERY; 1771 return NULL; 1772 } 1773 canonname = bp; 1774 bp += n; 1775 /* The qname can be abbreviated, but h_name is now absolute. */ 1776 qname = canonname; 1777 } 1778 haveanswer = 0; 1779 had_error = 0; 1780 srvlist = NULL; 1781 while (ancount-- > 0 && cp < eom && !had_error) { 1782 n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp)); 1783 if ((n < 0) || !maybe_ok(res, bp, name_ok)) { 1784 had_error++; 1785 continue; 1786 } 1787 cp += n; /* name */ 1788 type = _getshort(cp); 1789 cp += INT16SZ; /* type */ 1790 class = _getshort(cp); 1791 cp += INT16SZ + INT32SZ; /* class, TTL */ 1792 n = _getshort(cp); 1793 cp += INT16SZ; /* len */ 1794 if (class != C_IN) { 1795 /* XXX - debug? syslog? */ 1796 cp += n; 1797 continue; /* XXX - had_error++ ? */ 1798 } 1799 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1800 type == T_CNAME) { 1801 n = dn_expand(answer->buf, eom, cp, tbuf, (int)sizeof tbuf); 1802 if ((n < 0) || !maybe_ok(res, tbuf, name_ok)) { 1803 had_error++; 1804 continue; 1805 } 1806 cp += n; 1807 /* Get canonical name. */ 1808 n = (int)strlen(tbuf) + 1; /* for the \0 */ 1809 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1810 had_error++; 1811 continue; 1812 } 1813 strlcpy(bp, tbuf, (size_t)(ep - bp)); 1814 canonname = bp; 1815 bp += n; 1816 continue; 1817 } 1818 if (qtype == T_ANY) { 1819 if (!(type == T_A || type == T_AAAA)) { 1820 cp += n; 1821 continue; 1822 } 1823 } else if (type != qtype) { 1824 if (type != T_KEY && type != T_SIG && type != T_DNAME) { 1825 struct syslog_data sd = SYSLOG_DATA_INIT; 1826 syslog_r(LOG_NOTICE|LOG_AUTH, &sd, 1827 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1828 qname, p_class(C_IN), p_type(qtype), 1829 p_type(type)); 1830 } 1831 cp += n; 1832 continue; /* XXX - had_error++ ? */ 1833 } 1834 switch (type) { 1835 case T_A: 1836 case T_AAAA: 1837 if (strcasecmp(canonname, bp) != 0) { 1838 struct syslog_data sd = SYSLOG_DATA_INIT; 1839 syslog_r(LOG_NOTICE|LOG_AUTH, &sd, 1840 AskedForGot, canonname, bp); 1841 cp += n; 1842 continue; /* XXX - had_error++ ? */ 1843 } 1844 if (type == T_A && n != INADDRSZ) { 1845 cp += n; 1846 continue; 1847 } 1848 if (type == T_AAAA && n != IN6ADDRSZ) { 1849 cp += n; 1850 continue; 1851 } 1852 if (type == T_AAAA) { 1853 struct in6_addr in6; 1854 memcpy(&in6, cp, IN6ADDRSZ); 1855 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1856 cp += n; 1857 continue; 1858 } 1859 } 1860 if (!haveanswer) { 1861 int nn; 1862 1863 canonname = bp; 1864 nn = (int)strlen(bp) + 1; /* for the \0 */ 1865 bp += nn; 1866 } 1867 1868 /* don't overwrite pai */ 1869 ai = *pai; 1870 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1871 afd = find_afd(ai.ai_family); 1872 if (afd == NULL) { 1873 cp += n; 1874 continue; 1875 } 1876 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1877 if (cur->ai_next == NULL) 1878 had_error++; 1879 while (cur && cur->ai_next) 1880 cur = cur->ai_next; 1881 cp += n; 1882 break; 1883 case T_SRV: 1884 /* Add to SRV list. Insertion sort on priority. */ 1885 pri = _getshort(cp); 1886 cp += INT16SZ; 1887 weight = _getshort(cp); 1888 cp += INT16SZ; 1889 port = _getshort(cp); 1890 cp += INT16SZ; 1891 n = dn_expand(answer->buf, eom, cp, tbuf, 1892 (int)sizeof(tbuf)); 1893 if ((n < 0) || !maybe_ok(res, tbuf, res_hnok)) { 1894 had_error++; 1895 continue; 1896 } 1897 cp += n; 1898 if (strlen(tbuf) + 1 >= MAXDNAME) { 1899 had_error++; 1900 continue; 1901 } 1902 srv = malloc(sizeof(*srv)); 1903 if (!srv) { 1904 had_error++; 1905 continue; 1906 } 1907 strlcpy(srv->name, tbuf, sizeof(srv->name)); 1908 srv->pri = pri; 1909 srv->weight = weight; 1910 srv->port = port; 1911 /* Weight 0 is sorted before other weights. */ 1912 if (!srvlist 1913 || srv->pri < srvlist->pri 1914 || (srv->pri == srvlist->pri && 1915 (!srv->weight || srvlist->weight))) { 1916 srv->next = srvlist; 1917 srvlist = srv; 1918 } else { 1919 for (csrv = srvlist; 1920 csrv->next && csrv->next->pri <= srv->pri; 1921 csrv = csrv->next) { 1922 if (csrv->next->pri == srv->pri 1923 && (!srv->weight || 1924 csrv->next->weight)) 1925 break; 1926 } 1927 srv->next = csrv->next; 1928 csrv->next = srv; 1929 } 1930 continue; /* Don't add to haveanswer yet. */ 1931 default: 1932 abort(); 1933 } 1934 if (!had_error) 1935 haveanswer++; 1936 } 1937 1938 if (srvlist) { 1939 /* 1940 * Check for explicit rejection. 1941 */ 1942 if (!srvlist->next && !srvlist->name[0]) { 1943 free(srvlist); 1944 h_errno = HOST_NOT_FOUND; 1945 return NULL; 1946 } 1947 1948 while (srvlist) { 1949 struct res_target q, q2; 1950 1951 srv = srvlist; 1952 srvlist = srvlist->next; 1953 1954 /* 1955 * Since res_* doesn't give the additional 1956 * section, we always look up. 1957 */ 1958 memset(&q, 0, sizeof(q)); 1959 memset(&q2, 0, sizeof(q2)); 1960 1961 q.name = srv->name; 1962 q.qclass = C_IN; 1963 q.qtype = T_AAAA; 1964 q.next = &q2; 1965 q2.name = srv->name; 1966 q2.qclass = C_IN; 1967 q2.qtype = T_A; 1968 1969 aip = _dns_query(&q, pai, res, 0); 1970 1971 if (aip != NULL) { 1972 cur->ai_next = aip; 1973 while (cur && cur->ai_next) { 1974 cur = cur->ai_next; 1975 *getport(cur) = htons(srv->port); 1976 haveanswer++; 1977 } 1978 } 1979 free(srv); 1980 } 1981 } 1982 if (haveanswer) { 1983 if (!sentinel.ai_next->ai_canonname) 1984 (void)get_canonname(pai, sentinel.ai_next, 1985 canonname ? canonname : qname); 1986 h_errno = NETDB_SUCCESS; 1987 return sentinel.ai_next; 1988 } 1989 1990 /* We could have walked a CNAME chain, */ 1991 /* but the ultimate target may not have what we looked for */ 1992 h_errno = ntohs(hp->ancount) > 0? NO_DATA : NO_RECOVERY; 1993 return NULL; 1994 } 1995 1996 #define SORTEDADDR(p) (((struct sockaddr_in *)(void *)(p->ai_next->ai_addr))->sin_addr.s_addr) 1997 #define SORTMATCH(p, s) ((SORTEDADDR(p) & (s).mask) == (s).addr.s_addr) 1998 1999 static void 2000 aisort(struct addrinfo *s, res_state res) 2001 { 2002 struct addrinfo head, *t, *p; 2003 int i; 2004 2005 head.ai_next = NULL; 2006 t = &head; 2007 2008 for (i = 0; i < res->nsort; i++) { 2009 p = s; 2010 while (p->ai_next) { 2011 if ((p->ai_next->ai_family != AF_INET) 2012 || SORTMATCH(p, res->sort_list[i])) { 2013 t->ai_next = p->ai_next; 2014 t = t->ai_next; 2015 p->ai_next = p->ai_next->ai_next; 2016 } else { 2017 p = p->ai_next; 2018 } 2019 } 2020 } 2021 2022 /* add rest of list and reset s to the new list*/ 2023 t->ai_next = s->ai_next; 2024 s->ai_next = head.ai_next; 2025 } 2026 2027 static struct addrinfo * 2028 _dns_query(struct res_target *q, const struct addrinfo *pai, 2029 res_state res, int dosearch) 2030 { 2031 struct res_target *q2 = q->next; 2032 querybuf *buf, *buf2; 2033 struct addrinfo sentinel, *cur, *ai; 2034 2035 #ifdef DNS_DEBUG 2036 struct res_target *iter; 2037 for (iter = q; iter; iter = iter->next) 2038 printf("Query type %d for %s\n", iter->qtype, iter->name); 2039 #endif 2040 2041 buf = malloc(sizeof(*buf)); 2042 if (buf == NULL) { 2043 h_errno = NETDB_INTERNAL; 2044 return NULL; 2045 } 2046 buf2 = malloc(sizeof(*buf2)); 2047 if (buf2 == NULL) { 2048 free(buf); 2049 h_errno = NETDB_INTERNAL; 2050 return NULL; 2051 } 2052 2053 memset(&sentinel, 0, sizeof(sentinel)); 2054 cur = &sentinel; 2055 2056 q->answer = buf->buf; 2057 q->anslen = sizeof(buf->buf); 2058 if (q2) { 2059 q2->answer = buf2->buf; 2060 q2->anslen = sizeof(buf2->buf); 2061 } 2062 2063 if (dosearch) { 2064 if (res_searchN(q->name, q, res) < 0) 2065 goto out; 2066 } else { 2067 if (res_queryN(q->name, q, res) < 0) 2068 goto out; 2069 } 2070 2071 ai = getanswer(res, buf, q->n, q->name, q->qtype, pai); 2072 if (ai) { 2073 cur->ai_next = ai; 2074 while (cur && cur->ai_next) 2075 cur = cur->ai_next; 2076 } 2077 if (q2) { 2078 ai = getanswer(res, buf2, q2->n, q2->name, q2->qtype, pai); 2079 if (ai) 2080 cur->ai_next = ai; 2081 } 2082 free(buf); 2083 free(buf2); 2084 return sentinel.ai_next; 2085 out: 2086 free(buf); 2087 free(buf2); 2088 return NULL; 2089 } 2090 2091 /*ARGSUSED*/ 2092 static struct addrinfo * 2093 _dns_srv_lookup(const char *name, const char *servname, 2094 const struct addrinfo *pai) 2095 { 2096 static const char * const srvprotos[] = { "tcp", "udp" }; 2097 static const int srvnottype[] = { SOCK_DGRAM, SOCK_STREAM }; 2098 static const int nsrvprotos = 2; 2099 struct addrinfo sentinel, *cur, *ai; 2100 struct servent *serv, sv; 2101 struct servent_data svd; 2102 struct res_target q; 2103 res_state res; 2104 char *tname; 2105 int i; 2106 2107 res = __res_get_state(); 2108 if (res == NULL) 2109 return NULL; 2110 2111 memset(&svd, 0, sizeof(svd)); 2112 memset(&sentinel, 0, sizeof(sentinel)); 2113 cur = &sentinel; 2114 2115 /* 2116 * Iterate over supported SRV protocols. 2117 * (currently UDP and TCP only) 2118 */ 2119 for (i = 0; i < nsrvprotos; i++) { 2120 /* 2121 * Check that the caller didn't specify a hint 2122 * which precludes this protocol. 2123 */ 2124 if (pai->ai_socktype == srvnottype[i]) 2125 continue; 2126 /* 2127 * If the caller specified a port, 2128 * then lookup the database for the 2129 * official service name. 2130 */ 2131 serv = getservbyname_r(servname, srvprotos[i], &sv, &svd); 2132 if (serv == NULL) 2133 continue; 2134 2135 /* 2136 * Construct service DNS name. 2137 */ 2138 if (asprintf(&tname, "_%s._%s.%s", serv->s_name, serv->s_proto, 2139 name) < 0) 2140 continue; 2141 2142 memset(&q, 0, sizeof(q)); 2143 q.name = tname; 2144 q.qclass = C_IN; 2145 q.qtype = T_SRV; 2146 2147 /* 2148 * Do SRV query. 2149 */ 2150 ai = _dns_query(&q, pai, res, 1); 2151 if (ai) { 2152 cur->ai_next = ai; 2153 while (cur && cur->ai_next) 2154 cur = cur->ai_next; 2155 } 2156 free(tname); 2157 } 2158 2159 if (res->nsort) 2160 aisort(&sentinel, res); 2161 2162 __res_put_state(res); 2163 2164 return sentinel.ai_next; 2165 } 2166 2167 /*ARGSUSED*/ 2168 static struct addrinfo * 2169 _dns_host_lookup(const char *name, const struct addrinfo *pai) 2170 { 2171 struct res_target q, q2; 2172 struct addrinfo sentinel, *ai; 2173 res_state res; 2174 2175 res = __res_get_state(); 2176 if (res == NULL) 2177 return NULL; 2178 2179 memset(&q, 0, sizeof(q2)); 2180 memset(&q2, 0, sizeof(q2)); 2181 2182 switch (pai->ai_family) { 2183 case AF_UNSPEC: 2184 /* prefer IPv6 */ 2185 q.name = name; 2186 q.qclass = C_IN; 2187 q.qtype = T_AAAA; 2188 q.next = &q2; 2189 q2.name = name; 2190 q2.qclass = C_IN; 2191 q2.qtype = T_A; 2192 break; 2193 case AF_INET: 2194 q.name = name; 2195 q.qclass = C_IN; 2196 q.qtype = T_A; 2197 break; 2198 case AF_INET6: 2199 q.name = name; 2200 q.qclass = C_IN; 2201 q.qtype = T_AAAA; 2202 break; 2203 default: 2204 __res_put_state(res); 2205 h_errno = NETDB_INTERNAL; 2206 return NULL; 2207 } 2208 2209 ai = _dns_query(&q, pai, res, 1); 2210 2211 memset(&sentinel, 0, sizeof(sentinel)); 2212 sentinel.ai_next = ai; 2213 2214 if (ai != NULL && res->nsort) 2215 aisort(&sentinel, res); 2216 2217 __res_put_state(res); 2218 2219 return sentinel.ai_next; 2220 } 2221 2222 /*ARGSUSED*/ 2223 static int 2224 _dns_getaddrinfo(void *rv, void *cb_data, va_list ap) 2225 { 2226 struct addrinfo *ai = NULL; 2227 const char *name, *servname; 2228 const struct addrinfo *pai; 2229 2230 name = va_arg(ap, char *); 2231 pai = va_arg(ap, const struct addrinfo *); 2232 servname = va_arg(ap, char *); 2233 2234 /* 2235 * Try doing SRV lookup on service first. 2236 */ 2237 if (servname 2238 #ifdef AI_SRV 2239 && (pai->ai_flags & AI_SRV) 2240 #endif 2241 && !(pai->ai_flags & AI_NUMERICSERV) 2242 && str2number(servname) == -1) { 2243 2244 #ifdef DNS_DEBUG 2245 printf("%s: try SRV lookup\n", __func__); 2246 #endif 2247 ai = _dns_srv_lookup(name, servname, pai); 2248 } 2249 2250 /* 2251 * Do lookup on name. 2252 */ 2253 if (ai == NULL) { 2254 2255 #ifdef DNS_DEBUG 2256 printf("%s: try HOST lookup\n", __func__); 2257 #endif 2258 ai = _dns_host_lookup(name, pai); 2259 2260 if (ai == NULL) { 2261 switch (h_errno) { 2262 case HOST_NOT_FOUND: 2263 case NO_DATA: // XXX: Perhaps we could differentiate 2264 // So that we could return EAI_NODATA? 2265 return NS_NOTFOUND; 2266 case TRY_AGAIN: 2267 return NS_TRYAGAIN; 2268 default: 2269 return NS_UNAVAIL; 2270 } 2271 } 2272 } 2273 2274 *((struct addrinfo **)rv) = ai; 2275 return NS_SUCCESS; 2276 } 2277 2278 static void 2279 _sethtent(FILE **hostf) 2280 { 2281 2282 if (!*hostf) 2283 *hostf = fopen(_PATH_HOSTS, "re"); 2284 else 2285 rewind(*hostf); 2286 } 2287 2288 static void 2289 _endhtent(FILE **hostf) 2290 { 2291 2292 if (*hostf) { 2293 (void) fclose(*hostf); 2294 *hostf = NULL; 2295 } 2296 } 2297 2298 static struct addrinfo * 2299 _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2300 { 2301 char *p; 2302 char *cp, *tname, *cname; 2303 struct addrinfo hints, *res0, *res; 2304 int error; 2305 const char *addr; 2306 char hostbuf[8*1024]; 2307 2308 _DIAGASSERT(name != NULL); 2309 _DIAGASSERT(pai != NULL); 2310 2311 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "re"))) 2312 return NULL; 2313 again: 2314 if (!(p = fgets(hostbuf, (int)sizeof hostbuf, *hostf))) 2315 return NULL; 2316 if (*p == '#') 2317 goto again; 2318 if (!(cp = strpbrk(p, "#\n"))) 2319 goto again; 2320 *cp = '\0'; 2321 if (!(cp = strpbrk(p, " \t"))) 2322 goto again; 2323 *cp++ = '\0'; 2324 addr = p; 2325 /* if this is not something we're looking for, skip it. */ 2326 cname = NULL; 2327 while (cp && *cp) { 2328 if (*cp == ' ' || *cp == '\t') { 2329 cp++; 2330 continue; 2331 } 2332 if (!cname) 2333 cname = cp; 2334 tname = cp; 2335 if ((cp = strpbrk(cp, " \t")) != NULL) 2336 *cp++ = '\0'; 2337 if (strcasecmp(name, tname) == 0) 2338 goto found; 2339 } 2340 goto again; 2341 2342 found: 2343 hints = *pai; 2344 hints.ai_flags = AI_NUMERICHOST; 2345 error = getaddrinfo(addr, NULL, &hints, &res0); 2346 if (error) 2347 goto again; 2348 for (res = res0; res; res = res->ai_next) { 2349 /* cover it up */ 2350 res->ai_flags = pai->ai_flags; 2351 2352 if (pai->ai_flags & AI_CANONNAME) { 2353 if (get_canonname(pai, res, cname) != 0) { 2354 freeaddrinfo(res0); 2355 goto again; 2356 } 2357 } 2358 } 2359 return res0; 2360 } 2361 2362 /*ARGSUSED*/ 2363 static int 2364 _files_getaddrinfo(void *rv, void *cb_data, va_list ap) 2365 { 2366 const char *name; 2367 const struct addrinfo *pai; 2368 struct addrinfo sentinel, *cur; 2369 struct addrinfo *p; 2370 #ifndef _REENTRANT 2371 static 2372 #endif 2373 FILE *hostf = NULL; 2374 2375 name = va_arg(ap, char *); 2376 pai = va_arg(ap, const struct addrinfo *); 2377 2378 memset(&sentinel, 0, sizeof(sentinel)); 2379 cur = &sentinel; 2380 2381 _sethtent(&hostf); 2382 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2383 cur->ai_next = p; 2384 while (cur && cur->ai_next) 2385 cur = cur->ai_next; 2386 } 2387 _endhtent(&hostf); 2388 2389 *((struct addrinfo **)rv) = sentinel.ai_next; 2390 if (sentinel.ai_next == NULL) 2391 return NS_NOTFOUND; 2392 return NS_SUCCESS; 2393 } 2394 2395 #ifdef YP 2396 /*ARGSUSED*/ 2397 static struct addrinfo * 2398 _yphostent(char *line, const struct addrinfo *pai) 2399 { 2400 struct addrinfo sentinel, *cur; 2401 struct addrinfo hints, *res, *res0; 2402 int error; 2403 char *p; 2404 const char *addr, *canonname; 2405 char *nextline; 2406 char *cp; 2407 2408 _DIAGASSERT(line != NULL); 2409 _DIAGASSERT(pai != NULL); 2410 2411 p = line; 2412 addr = canonname = NULL; 2413 2414 memset(&sentinel, 0, sizeof(sentinel)); 2415 cur = &sentinel; 2416 2417 nextline: 2418 /* terminate line */ 2419 cp = strchr(p, '\n'); 2420 if (cp) { 2421 *cp++ = '\0'; 2422 nextline = cp; 2423 } else 2424 nextline = NULL; 2425 2426 cp = strpbrk(p, " \t"); 2427 if (cp == NULL) { 2428 if (canonname == NULL) 2429 return NULL; 2430 else 2431 goto done; 2432 } 2433 *cp++ = '\0'; 2434 2435 addr = p; 2436 2437 while (cp && *cp) { 2438 if (*cp == ' ' || *cp == '\t') { 2439 cp++; 2440 continue; 2441 } 2442 if (!canonname) 2443 canonname = cp; 2444 if ((cp = strpbrk(cp, " \t")) != NULL) 2445 *cp++ = '\0'; 2446 } 2447 2448 hints = *pai; 2449 hints.ai_flags = AI_NUMERICHOST; 2450 error = getaddrinfo(addr, NULL, &hints, &res0); 2451 if (error == 0) { 2452 for (res = res0; res; res = res->ai_next) { 2453 /* cover it up */ 2454 res->ai_flags = pai->ai_flags; 2455 2456 if (pai->ai_flags & AI_CANONNAME) 2457 (void)get_canonname(pai, res, canonname); 2458 } 2459 } else 2460 res0 = NULL; 2461 if (res0) { 2462 cur->ai_next = res0; 2463 while (cur->ai_next) 2464 cur = cur->ai_next; 2465 } 2466 2467 if (nextline) { 2468 p = nextline; 2469 goto nextline; 2470 } 2471 2472 done: 2473 return sentinel.ai_next; 2474 } 2475 2476 /*ARGSUSED*/ 2477 static int 2478 _yp_getaddrinfo(void *rv, void *cb_data, va_list ap) 2479 { 2480 struct addrinfo sentinel, *cur; 2481 struct addrinfo *ai = NULL; 2482 char *ypbuf; 2483 int ypbuflen, r; 2484 const char *name; 2485 const struct addrinfo *pai; 2486 char *ypdomain; 2487 2488 if (_yp_check(&ypdomain) == 0) 2489 return NS_UNAVAIL; 2490 2491 name = va_arg(ap, char *); 2492 pai = va_arg(ap, const struct addrinfo *); 2493 2494 memset(&sentinel, 0, sizeof(sentinel)); 2495 cur = &sentinel; 2496 2497 /* hosts.byname is only for IPv4 (Solaris8) */ 2498 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2499 r = yp_match(ypdomain, "hosts.byname", name, 2500 (int)strlen(name), &ypbuf, &ypbuflen); 2501 if (r == 0) { 2502 struct addrinfo ai4; 2503 2504 ai4 = *pai; 2505 ai4.ai_family = AF_INET; 2506 ai = _yphostent(ypbuf, &ai4); 2507 if (ai) { 2508 cur->ai_next = ai; 2509 while (cur && cur->ai_next) 2510 cur = cur->ai_next; 2511 } 2512 } 2513 free(ypbuf); 2514 } 2515 2516 /* ipnodes.byname can hold both IPv4/v6 */ 2517 r = yp_match(ypdomain, "ipnodes.byname", name, 2518 (int)strlen(name), &ypbuf, &ypbuflen); 2519 if (r == 0) { 2520 ai = _yphostent(ypbuf, pai); 2521 if (ai) 2522 cur->ai_next = ai; 2523 free(ypbuf); 2524 } 2525 2526 if (sentinel.ai_next == NULL) { 2527 h_errno = HOST_NOT_FOUND; 2528 return NS_NOTFOUND; 2529 } 2530 *((struct addrinfo **)rv) = sentinel.ai_next; 2531 return NS_SUCCESS; 2532 } 2533 #endif 2534 2535 /* resolver logic */ 2536 2537 /* 2538 * Formulate a normal query, send, and await answer. 2539 * Returned answer is placed in supplied buffer "answer". 2540 * Perform preliminary check of answer, returning success only 2541 * if no error is indicated and the answer count is nonzero. 2542 * Return the size of the response on success, -1 on error. 2543 * Error number is left in h_errno. 2544 * 2545 * Caller must parse answer and determine whether it answers the question. 2546 */ 2547 static int 2548 res_queryN(const char *name, /* domain name */ struct res_target *target, 2549 res_state statp) 2550 { 2551 u_char buf[MAXPACKET]; 2552 HEADER *hp; 2553 int n; 2554 struct res_target *t; 2555 int rcode; 2556 u_char *rdata; 2557 int ancount; 2558 2559 _DIAGASSERT(name != NULL); 2560 /* XXX: target may be NULL??? */ 2561 2562 rcode = NOERROR; 2563 ancount = 0; 2564 2565 for (t = target; t; t = t->next) { 2566 int class, type; 2567 u_char *answer; 2568 int anslen; 2569 u_int oflags; 2570 2571 hp = (HEADER *)(void *)t->answer; 2572 oflags = statp->_flags; 2573 2574 again: 2575 hp->rcode = NOERROR; /* default */ 2576 2577 /* make it easier... */ 2578 class = t->qclass; 2579 type = t->qtype; 2580 answer = t->answer; 2581 anslen = t->anslen; 2582 #ifdef DEBUG 2583 if (statp->options & RES_DEBUG) 2584 printf(";; res_nquery(%s, %d, %d)\n", name, class, type); 2585 #endif 2586 2587 n = res_nmkquery(statp, QUERY, name, class, type, NULL, 0, NULL, 2588 buf, (int)sizeof(buf)); 2589 #ifdef RES_USE_EDNS0 2590 if (n > 0 && (statp->_flags & RES_F_EDNS0ERR) == 0 && 2591 (statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0) { 2592 n = res_nopt(statp, n, buf, (int)sizeof(buf), anslen); 2593 rdata = &buf[n]; 2594 if (n > 0 && (statp->options & RES_NSID) != 0U) { 2595 n = res_nopt_rdata(statp, n, buf, 2596 (int)sizeof(buf), 2597 rdata, NS_OPT_NSID, 0, NULL); 2598 } 2599 } 2600 #endif 2601 if (n <= 0) { 2602 #ifdef DEBUG 2603 if (statp->options & RES_DEBUG) 2604 printf(";; res_nquery: mkquery failed\n"); 2605 #endif 2606 h_errno = NO_RECOVERY; 2607 return n; 2608 } 2609 n = res_nsend(statp, buf, n, answer, anslen); 2610 if (n < 0) { 2611 #ifdef RES_USE_EDNS0 2612 /* if the query choked with EDNS0, retry without EDNS0 */ 2613 if ((statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U && 2614 ((oflags ^ statp->_flags) & RES_F_EDNS0ERR) != 0) { 2615 statp->_flags |= RES_F_EDNS0ERR; 2616 if (statp->options & RES_DEBUG) 2617 printf(";; res_nquery: retry without EDNS0\n"); 2618 goto again; 2619 } 2620 #endif 2621 #if 0 2622 #ifdef DEBUG 2623 if (statp->options & RES_DEBUG) 2624 printf(";; res_query: send error\n"); 2625 #endif 2626 h_errno = TRY_AGAIN; 2627 return n; 2628 #endif 2629 } 2630 2631 if (n < 0 || hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2632 rcode = hp->rcode; /* record most recent error */ 2633 #ifdef DEBUG 2634 if (statp->options & RES_DEBUG) 2635 printf(";; rcode = (%s), counts = an:%d ns:%d ar:%d\n", 2636 p_rcode(hp->rcode), 2637 ntohs(hp->ancount), 2638 ntohs(hp->nscount), 2639 ntohs(hp->arcount)); 2640 #endif 2641 continue; 2642 } 2643 2644 ancount += ntohs(hp->ancount); 2645 2646 t->n = n; 2647 } 2648 2649 if (ancount == 0) { 2650 switch (rcode) { 2651 case NXDOMAIN: 2652 h_errno = HOST_NOT_FOUND; 2653 break; 2654 case SERVFAIL: 2655 h_errno = TRY_AGAIN; 2656 break; 2657 case NOERROR: 2658 h_errno = NO_DATA; 2659 break; 2660 case FORMERR: 2661 case NOTIMP: 2662 case REFUSED: 2663 default: 2664 h_errno = NO_RECOVERY; 2665 break; 2666 } 2667 return -1; 2668 } 2669 return ancount; 2670 } 2671 2672 /* 2673 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2674 * Return the size of the response on success, -1 on error. 2675 * If enabled, implement search rules until answer or unrecoverable failure 2676 * is detected. Error code, if any, is left in h_errno. 2677 */ 2678 static int 2679 res_searchN(const char *name, struct res_target *target, res_state res) 2680 { 2681 const char *cp, * const *domain; 2682 HEADER *hp; 2683 u_int dots; 2684 char buf[MAXHOSTNAMELEN]; 2685 int trailing_dot, ret, saved_herrno; 2686 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 2687 2688 _DIAGASSERT(name != NULL); 2689 _DIAGASSERT(target != NULL); 2690 2691 hp = (HEADER *)(void *)target->answer; /*XXX*/ 2692 2693 errno = 0; 2694 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 2695 dots = 0; 2696 for (cp = name; *cp; cp++) 2697 dots += (*cp == '.'); 2698 trailing_dot = 0; 2699 if (cp > name && *--cp == '.') 2700 trailing_dot++; 2701 2702 /* 2703 * if there aren't any dots, it could be a user-level alias 2704 */ 2705 if (!dots && (cp = res_hostalias(res, name, buf, sizeof(buf))) != NULL) { 2706 ret = res_queryN(cp, target, res); 2707 return ret; 2708 } 2709 2710 /* 2711 * If there are dots in the name already, let's just give it a try 2712 * 'as is'. The threshold can be set with the "ndots" option. 2713 */ 2714 saved_herrno = -1; 2715 if (dots >= res->ndots) { 2716 ret = res_querydomainN(name, NULL, target, res); 2717 if (ret > 0) 2718 return ret; 2719 saved_herrno = h_errno; 2720 tried_as_is++; 2721 } 2722 2723 /* 2724 * We do at least one level of search if 2725 * - there is no dot and RES_DEFNAME is set, or 2726 * - there is at least one dot, there is no trailing dot, 2727 * and RES_DNSRCH is set. 2728 */ 2729 if ((!dots && (res->options & RES_DEFNAMES)) || 2730 (dots && !trailing_dot && (res->options & RES_DNSRCH))) { 2731 int done = 0; 2732 2733 for (domain = (const char * const *)res->dnsrch; 2734 *domain && !done; 2735 domain++) { 2736 2737 ret = res_querydomainN(name, *domain, target, res); 2738 if (ret > 0) 2739 return ret; 2740 2741 /* 2742 * If no server present, give up. 2743 * If name isn't found in this domain, 2744 * keep trying higher domains in the search list 2745 * (if that's enabled). 2746 * On a NO_DATA error, keep trying, otherwise 2747 * a wildcard entry of another type could keep us 2748 * from finding this entry higher in the domain. 2749 * If we get some other error (negative answer or 2750 * server failure), then stop searching up, 2751 * but try the input name below in case it's 2752 * fully-qualified. 2753 */ 2754 if (errno == ECONNREFUSED) { 2755 h_errno = TRY_AGAIN; 2756 return -1; 2757 } 2758 2759 switch (h_errno) { 2760 case NO_DATA: 2761 got_nodata++; 2762 /* FALLTHROUGH */ 2763 case HOST_NOT_FOUND: 2764 /* keep trying */ 2765 break; 2766 case TRY_AGAIN: 2767 if (hp->rcode == SERVFAIL) { 2768 /* try next search element, if any */ 2769 got_servfail++; 2770 break; 2771 } 2772 /* FALLTHROUGH */ 2773 default: 2774 /* anything else implies that we're done */ 2775 done++; 2776 } 2777 /* 2778 * if we got here for some reason other than DNSRCH, 2779 * we only wanted one iteration of the loop, so stop. 2780 */ 2781 if (!(res->options & RES_DNSRCH)) 2782 done++; 2783 } 2784 } 2785 2786 /* 2787 * if we have not already tried the name "as is", do that now. 2788 * note that we do this regardless of how many dots were in the 2789 * name or whether it ends with a dot. 2790 */ 2791 if (!tried_as_is) { 2792 ret = res_querydomainN(name, NULL, target, res); 2793 if (ret > 0) 2794 return ret; 2795 } 2796 2797 /* 2798 * if we got here, we didn't satisfy the search. 2799 * if we did an initial full query, return that query's h_errno 2800 * (note that we wouldn't be here if that query had succeeded). 2801 * else if we ever got a nodata, send that back as the reason. 2802 * else send back meaningless h_errno, that being the one from 2803 * the last DNSRCH we did. 2804 */ 2805 if (saved_herrno != -1) 2806 h_errno = saved_herrno; 2807 else if (got_nodata) 2808 h_errno = NO_DATA; 2809 else if (got_servfail) 2810 h_errno = TRY_AGAIN; 2811 return -1; 2812 } 2813 2814 /* 2815 * Perform a call on res_query on the concatenation of name and domain, 2816 * removing a trailing dot from name if domain is NULL. 2817 */ 2818 static int 2819 res_querydomainN(const char *name, const char *domain, 2820 struct res_target *target, res_state res) 2821 { 2822 char nbuf[MAXDNAME]; 2823 const char *longname = nbuf; 2824 size_t n; 2825 2826 _DIAGASSERT(name != NULL); 2827 /* XXX: target may be NULL??? */ 2828 2829 #ifdef DEBUG 2830 if (res->options & RES_DEBUG) 2831 printf(";; res_querydomain(%s, %s)\n", 2832 name, domain?domain:"<Nil>"); 2833 #endif 2834 if (domain == NULL) { 2835 /* 2836 * Check for trailing '.'; 2837 * copy without '.' if present. 2838 */ 2839 n = strlen(name); 2840 if (n + 1 > sizeof(nbuf)) { 2841 h_errno = NO_RECOVERY; 2842 return -1; 2843 } 2844 if (n > 0 && name[--n] == '.') { 2845 snprintf(nbuf, sizeof(nbuf), "%*s", (int)n, name); 2846 } else 2847 longname = name; 2848 } else { 2849 if ((size_t)snprintf(nbuf, sizeof(nbuf), "%s.%s", 2850 name, domain) >= sizeof(nbuf)) { 2851 h_errno = NO_RECOVERY; 2852 return -1; 2853 } 2854 } 2855 return res_queryN(longname, target, res); 2856 } 2857 2858 #ifdef TEST 2859 int 2860 main(int argc, char *argv[]) { 2861 struct addrinfo *ai, *sai; 2862 int i, e; 2863 char buf[1024]; 2864 2865 for (i = 1; i < argc; i++) { 2866 if ((e = getaddrinfo(argv[i], NULL, NULL, &sai)) != 0) 2867 warnx("%s: %s", argv[i], gai_strerror(e)); 2868 for (ai = sai; ai; ai = ai->ai_next) { 2869 sockaddr_snprintf(buf, sizeof(buf), "%a", ai->ai_addr); 2870 printf("flags=0x%x family=%d socktype=%d protocol=%d " 2871 "addrlen=%zu addr=%s canonname=%s next=%p\n", 2872 ai->ai_flags, 2873 ai->ai_family, 2874 ai->ai_socktype, 2875 ai->ai_protocol, 2876 (size_t)ai->ai_addrlen, 2877 buf, 2878 ai->ai_canonname, 2879 ai->ai_next); 2880 } 2881 if (sai) 2882 freeaddrinfo(sai); 2883 } 2884 return 0; 2885 } 2886 #endif 2887
Indexes created Fri Sep 26 08:10:20 GMT 2025