1 /* $NetBSD: getaddrinfo.c,v 1.124 2023/08/01 08:47:25 mrg 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 1.124 2023/08/01 08:47:25 mrg 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 u_int32_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(char *, struct sockaddr_in6 *, u_int32_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 u_int32_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 *cp, *hostname2 = NULL, *scope, *addr; 1397 struct sockaddr_in6 *sin6; 1398 1399 _DIAGASSERT(pai != NULL); 1400 /* hostname may be NULL */ 1401 /* servname may be NULL */ 1402 _DIAGASSERT(res != NULL); 1403 1404 /* 1405 * if the servname does not match socktype/protocol, ignore it. 1406 */ 1407 if (get_portmatch(pai, servname, svd) != 0) 1408 return 0; 1409 1410 afd = find_afd(pai->ai_family); 1411 if (afd == NULL) 1412 return 0; 1413 1414 if (!afd->a_scoped) 1415 return explore_numeric(pai, hostname, servname, res, hostname, 1416 svd); 1417 1418 cp = strchr(hostname, SCOPE_DELIMITER); 1419 if (cp == NULL) 1420 return explore_numeric(pai, hostname, servname, res, hostname, 1421 svd); 1422 1423 /* 1424 * Handle special case of <scoped_address><delimiter><scope id> 1425 */ 1426 hostname2 = strdup(hostname); 1427 if (hostname2 == NULL) 1428 return EAI_MEMORY; 1429 /* terminate at the delimiter */ 1430 hostname2[cp - hostname] = '\0'; 1431 addr = hostname2; 1432 scope = cp + 1; 1433 1434 error = explore_numeric(pai, addr, servname, res, hostname, svd); 1435 if (error == 0) { 1436 u_int32_t scopeid; 1437 1438 for (cur = *res; cur; cur = cur->ai_next) { 1439 if (cur->ai_family != AF_INET6) 1440 continue; 1441 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1442 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1443 free(hostname2); 1444 return EAI_NODATA; /* XXX: is return OK? */ 1445 } 1446 sin6->sin6_scope_id = scopeid; 1447 } 1448 } 1449 1450 free(hostname2); 1451 1452 return error; 1453 #endif 1454 } 1455 1456 static int 1457 get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) 1458 { 1459 1460 _DIAGASSERT(pai != NULL); 1461 _DIAGASSERT(ai != NULL); 1462 _DIAGASSERT(str != NULL); 1463 1464 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1465 ai->ai_canonname = strdup(str); 1466 if (ai->ai_canonname == NULL) 1467 return EAI_MEMORY; 1468 } 1469 return 0; 1470 } 1471 1472 struct addrinfo * 1473 allocaddrinfo(socklen_t addrlen) 1474 { 1475 struct addrinfo *ai; 1476 1477 ai = calloc(sizeof(struct addrinfo) + addrlen, 1); 1478 if (ai) { 1479 ai->ai_addr = (void *)(ai+1); 1480 ai->ai_addrlen = ai->ai_addr->sa_len = addrlen; 1481 } 1482 1483 return ai; 1484 } 1485 1486 static struct addrinfo * 1487 get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) 1488 { 1489 char *p; 1490 struct addrinfo *ai; 1491 struct sockaddr *save; 1492 1493 _DIAGASSERT(pai != NULL); 1494 _DIAGASSERT(afd != NULL); 1495 _DIAGASSERT(addr != NULL); 1496 1497 ai = allocaddrinfo((socklen_t)afd->a_socklen); 1498 if (ai == NULL) 1499 return NULL; 1500 1501 save = ai->ai_addr; 1502 memcpy(ai, pai, sizeof(struct addrinfo)); 1503 1504 /* since we just overwrote all of ai, we have 1505 to restore ai_addr and ai_addrlen */ 1506 ai->ai_addr = save; 1507 ai->ai_addrlen = (socklen_t)afd->a_socklen; 1508 1509 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1510 p = (char *)(void *)(ai->ai_addr); 1511 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1512 return ai; 1513 } 1514 1515 static int 1516 get_portmatch(const struct addrinfo *ai, const char *servname, 1517 struct servent_data *svd) 1518 { 1519 1520 _DIAGASSERT(ai != NULL); 1521 /* servname may be NULL */ 1522 1523 return get_port(ai, servname, 1, svd); 1524 } 1525 1526 static int 1527 get_port(const struct addrinfo *ai, const char *servname, int matchonly, 1528 struct servent_data *svd) 1529 { 1530 const char *proto; 1531 struct servent *sp; 1532 int port; 1533 int allownumeric; 1534 1535 _DIAGASSERT(ai != NULL); 1536 /* servname may be NULL */ 1537 1538 if (servname == NULL) 1539 return 0; 1540 switch (ai->ai_family) { 1541 case AF_INET: 1542 #ifdef AF_INET6 1543 case AF_INET6: 1544 #endif 1545 break; 1546 default: 1547 return 0; 1548 } 1549 1550 switch (ai->ai_socktype) { 1551 case SOCK_RAW: 1552 return EAI_SERVICE; 1553 case SOCK_DGRAM: 1554 case SOCK_STREAM: 1555 allownumeric = 1; 1556 break; 1557 case ANY: 1558 /* 1559 * This was 0. It is now 1 so that queries specifying 1560 * a NULL hint, or hint without socktype (but, hopefully, 1561 * with protocol) and numeric address actually work. 1562 */ 1563 allownumeric = 1; 1564 break; 1565 default: 1566 return EAI_SOCKTYPE; 1567 } 1568 1569 port = str2number(servname); 1570 if (port >= 0) { 1571 if (!allownumeric) 1572 return EAI_SERVICE; 1573 if (port < 0 || port > 65535) 1574 return EAI_SERVICE; 1575 port = htons(port); 1576 } else { 1577 struct servent sv; 1578 if (ai->ai_flags & AI_NUMERICSERV) 1579 return EAI_NONAME; 1580 1581 switch (ai->ai_socktype) { 1582 case SOCK_DGRAM: 1583 proto = "udp"; 1584 break; 1585 case SOCK_STREAM: 1586 proto = "tcp"; 1587 break; 1588 default: 1589 proto = NULL; 1590 break; 1591 } 1592 1593 sp = getservbyname_r(servname, proto, &sv, svd); 1594 if (sp == NULL) 1595 return EAI_SERVICE; 1596 port = sp->s_port; 1597 } 1598 1599 if (!matchonly) 1600 *getport(__UNCONST(ai)) = port; 1601 return 0; 1602 } 1603 1604 static const struct afd * 1605 find_afd(int af) 1606 { 1607 const struct afd *afd; 1608 1609 if (af == PF_UNSPEC) 1610 return NULL; 1611 for (afd = afdl; afd->a_af; afd++) { 1612 if (afd->a_af == af) 1613 return afd; 1614 } 1615 return NULL; 1616 } 1617 1618 /* 1619 * AI_ADDRCONFIG check: Build a mask containing a bit set for each address 1620 * family configured in the system. 1621 * 1622 */ 1623 static int 1624 addrconfig(uint64_t *mask) 1625 { 1626 struct ifaddrs *ifaddrs, *ifa; 1627 1628 if (getifaddrs(&ifaddrs) == -1) 1629 return -1; 1630 1631 *mask = 0; 1632 for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) 1633 if (ifa->ifa_addr && (ifa->ifa_flags & IFF_UP)) { 1634 _DIAGASSERT(ifa->ifa_addr->sa_family < 64); 1635 *mask |= (uint64_t)1 << ifa->ifa_addr->sa_family; 1636 } 1637 1638 freeifaddrs(ifaddrs); 1639 return 0; 1640 } 1641 1642 #ifdef INET6 1643 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1644 static int 1645 ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid) 1646 { 1647 u_long lscopeid; 1648 struct in6_addr *a6; 1649 char *ep; 1650 1651 _DIAGASSERT(scope != NULL); 1652 _DIAGASSERT(sin6 != NULL); 1653 _DIAGASSERT(scopeid != NULL); 1654 1655 a6 = &sin6->sin6_addr; 1656 1657 /* empty scopeid portion is invalid */ 1658 if (*scope == '\0') 1659 return -1; 1660 1661 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1662 /* 1663 * We currently assume a one-to-one mapping between links 1664 * and interfaces, so we simply use interface indices for 1665 * like-local scopes. 1666 */ 1667 *scopeid = if_nametoindex(scope); 1668 if (*scopeid == 0) 1669 goto trynumeric; 1670 return 0; 1671 } 1672 1673 /* still unclear about literal, allow numeric only - placeholder */ 1674 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1675 goto trynumeric; 1676 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1677 goto trynumeric; 1678 else 1679 goto trynumeric; /* global */ 1680 1681 /* try to convert to a numeric id as a last resort */ 1682 trynumeric: 1683 errno = 0; 1684 lscopeid = strtoul(scope, &ep, 10); 1685 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1686 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1687 return 0; 1688 else 1689 return -1; 1690 } 1691 #endif 1692 1693 /* code duplicate with gethnamaddr.c */ 1694 1695 static const char AskedForGot[] = 1696 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1697 1698 #define maybe_ok(res, nm, ok) (((res)->options & RES_NOCHECKNAME) != 0U || \ 1699 (ok)(nm) != 0) 1700 static struct addrinfo * 1701 getanswer(res_state res, const querybuf *answer, int anslen, const char *qname, 1702 int qtype, const struct addrinfo *pai) 1703 { 1704 struct addrinfo sentinel, *cur; 1705 struct addrinfo ai, *aip; 1706 const struct afd *afd; 1707 char *canonname; 1708 const HEADER *hp; 1709 const u_char *cp; 1710 int n; 1711 const u_char *eom; 1712 char *bp, *ep; 1713 int type, class, ancount, qdcount; 1714 int haveanswer, had_error; 1715 char tbuf[MAXDNAME]; 1716 int (*name_ok) (const char *); 1717 char hostbuf[8*1024]; 1718 int port, pri, weight; 1719 struct srvinfo *srvlist, *srv, *csrv; 1720 1721 _DIAGASSERT(answer != NULL); 1722 _DIAGASSERT(qname != NULL); 1723 _DIAGASSERT(pai != NULL); 1724 _DIAGASSERT(res != NULL); 1725 1726 memset(&sentinel, 0, sizeof(sentinel)); 1727 cur = &sentinel; 1728 1729 canonname = NULL; 1730 eom = answer->buf + anslen; 1731 switch (qtype) { 1732 case T_A: 1733 case T_AAAA: 1734 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1735 name_ok = res_hnok; 1736 break; 1737 case T_SRV: 1738 name_ok = gai_srvok; 1739 break; 1740 default: 1741 return NULL; /* XXX should be abort(); */ 1742 } 1743 /* 1744 * find first satisfactory answer 1745 */ 1746 hp = &answer->hdr; 1747 ancount = ntohs(hp->ancount); 1748 qdcount = ntohs(hp->qdcount); 1749 bp = hostbuf; 1750 ep = hostbuf + sizeof hostbuf; 1751 cp = answer->buf + HFIXEDSZ; 1752 if (qdcount != 1) { 1753 h_errno = NO_RECOVERY; 1754 return NULL; 1755 } 1756 n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp)); 1757 if ((n < 0) || !maybe_ok(res, bp, name_ok)) { 1758 h_errno = NO_RECOVERY; 1759 return NULL; 1760 } 1761 cp += n + QFIXEDSZ; 1762 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1763 /* res_send() has already verified that the query name is the 1764 * same as the one we sent; this just gets the expanded name 1765 * (i.e., with the succeeding search-domain tacked on). 1766 */ 1767 n = (int)strlen(bp) + 1; /* for the \0 */ 1768 if (n >= MAXHOSTNAMELEN) { 1769 h_errno = NO_RECOVERY; 1770 return NULL; 1771 } 1772 canonname = bp; 1773 bp += n; 1774 /* The qname can be abbreviated, but h_name is now absolute. */ 1775 qname = canonname; 1776 } 1777 haveanswer = 0; 1778 had_error = 0; 1779 srvlist = NULL; 1780 while (ancount-- > 0 && cp < eom && !had_error) { 1781 n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp)); 1782 if ((n < 0) || !maybe_ok(res, bp, name_ok)) { 1783 had_error++; 1784 continue; 1785 } 1786 cp += n; /* name */ 1787 type = _getshort(cp); 1788 cp += INT16SZ; /* type */ 1789 class = _getshort(cp); 1790 cp += INT16SZ + INT32SZ; /* class, TTL */ 1791 n = _getshort(cp); 1792 cp += INT16SZ; /* len */ 1793 if (class != C_IN) { 1794 /* XXX - debug? syslog? */ 1795 cp += n; 1796 continue; /* XXX - had_error++ ? */ 1797 } 1798 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1799 type == T_CNAME) { 1800 n = dn_expand(answer->buf, eom, cp, tbuf, (int)sizeof tbuf); 1801 if ((n < 0) || !maybe_ok(res, tbuf, name_ok)) { 1802 had_error++; 1803 continue; 1804 } 1805 cp += n; 1806 /* Get canonical name. */ 1807 n = (int)strlen(tbuf) + 1; /* for the \0 */ 1808 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1809 had_error++; 1810 continue; 1811 } 1812 strlcpy(bp, tbuf, (size_t)(ep - bp)); 1813 canonname = bp; 1814 bp += n; 1815 continue; 1816 } 1817 if (qtype == T_ANY) { 1818 if (!(type == T_A || type == T_AAAA)) { 1819 cp += n; 1820 continue; 1821 } 1822 } else if (type != qtype) { 1823 if (type != T_KEY && type != T_SIG && type != T_DNAME) { 1824 struct syslog_data sd = SYSLOG_DATA_INIT; 1825 syslog_r(LOG_NOTICE|LOG_AUTH, &sd, 1826 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1827 qname, p_class(C_IN), p_type(qtype), 1828 p_type(type)); 1829 } 1830 cp += n; 1831 continue; /* XXX - had_error++ ? */ 1832 } 1833 switch (type) { 1834 case T_A: 1835 case T_AAAA: 1836 if (strcasecmp(canonname, bp) != 0) { 1837 struct syslog_data sd = SYSLOG_DATA_INIT; 1838 syslog_r(LOG_NOTICE|LOG_AUTH, &sd, 1839 AskedForGot, canonname, bp); 1840 cp += n; 1841 continue; /* XXX - had_error++ ? */ 1842 } 1843 if (type == T_A && n != INADDRSZ) { 1844 cp += n; 1845 continue; 1846 } 1847 if (type == T_AAAA && n != IN6ADDRSZ) { 1848 cp += n; 1849 continue; 1850 } 1851 if (type == T_AAAA) { 1852 struct in6_addr in6; 1853 memcpy(&in6, cp, IN6ADDRSZ); 1854 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1855 cp += n; 1856 continue; 1857 } 1858 } 1859 if (!haveanswer) { 1860 int nn; 1861 1862 canonname = bp; 1863 nn = (int)strlen(bp) + 1; /* for the \0 */ 1864 bp += nn; 1865 } 1866 1867 /* don't overwrite pai */ 1868 ai = *pai; 1869 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1870 afd = find_afd(ai.ai_family); 1871 if (afd == NULL) { 1872 cp += n; 1873 continue; 1874 } 1875 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1876 if (cur->ai_next == NULL) 1877 had_error++; 1878 while (cur && cur->ai_next) 1879 cur = cur->ai_next; 1880 cp += n; 1881 break; 1882 case T_SRV: 1883 /* Add to SRV list. Insertion sort on priority. */ 1884 pri = _getshort(cp); 1885 cp += INT16SZ; 1886 weight = _getshort(cp); 1887 cp += INT16SZ; 1888 port = _getshort(cp); 1889 cp += INT16SZ; 1890 n = dn_expand(answer->buf, eom, cp, tbuf, 1891 (int)sizeof(tbuf)); 1892 if ((n < 0) || !maybe_ok(res, tbuf, res_hnok)) { 1893 had_error++; 1894 continue; 1895 } 1896 cp += n; 1897 if (strlen(tbuf) + 1 >= MAXDNAME) { 1898 had_error++; 1899 continue; 1900 } 1901 srv = malloc(sizeof(*srv)); 1902 if (!srv) { 1903 had_error++; 1904 continue; 1905 } 1906 strlcpy(srv->name, tbuf, sizeof(srv->name)); 1907 srv->pri = pri; 1908 srv->weight = weight; 1909 srv->port = port; 1910 /* Weight 0 is sorted before other weights. */ 1911 if (!srvlist 1912 || srv->pri < srvlist->pri 1913 || (srv->pri == srvlist->pri && 1914 (!srv->weight || srvlist->weight))) { 1915 srv->next = srvlist; 1916 srvlist = srv; 1917 } else { 1918 for (csrv = srvlist; 1919 csrv->next && csrv->next->pri <= srv->pri; 1920 csrv = csrv->next) { 1921 if (csrv->next->pri == srv->pri 1922 && (!srv->weight || 1923 csrv->next->weight)) 1924 break; 1925 } 1926 srv->next = csrv->next; 1927 csrv->next = srv; 1928 } 1929 continue; /* Don't add to haveanswer yet. */ 1930 default: 1931 abort(); 1932 } 1933 if (!had_error) 1934 haveanswer++; 1935 } 1936 1937 if (srvlist) { 1938 /* 1939 * Check for explicit rejection. 1940 */ 1941 if (!srvlist->next && !srvlist->name[0]) { 1942 free(srvlist); 1943 h_errno = HOST_NOT_FOUND; 1944 return NULL; 1945 } 1946 1947 while (srvlist) { 1948 struct res_target q, q2; 1949 1950 srv = srvlist; 1951 srvlist = srvlist->next; 1952 1953 /* 1954 * Since res_* doesn't give the additional 1955 * section, we always look up. 1956 */ 1957 memset(&q, 0, sizeof(q)); 1958 memset(&q2, 0, sizeof(q2)); 1959 1960 q.name = srv->name; 1961 q.qclass = C_IN; 1962 q.qtype = T_AAAA; 1963 q.next = &q2; 1964 q2.name = srv->name; 1965 q2.qclass = C_IN; 1966 q2.qtype = T_A; 1967 1968 aip = _dns_query(&q, pai, res, 0); 1969 1970 if (aip != NULL) { 1971 cur->ai_next = aip; 1972 while (cur && cur->ai_next) { 1973 cur = cur->ai_next; 1974 *getport(cur) = htons(srv->port); 1975 haveanswer++; 1976 } 1977 } 1978 free(srv); 1979 } 1980 } 1981 if (haveanswer) { 1982 if (!sentinel.ai_next->ai_canonname) 1983 (void)get_canonname(pai, sentinel.ai_next, 1984 canonname ? canonname : qname); 1985 h_errno = NETDB_SUCCESS; 1986 return sentinel.ai_next; 1987 } 1988 1989 /* We could have walked a CNAME chain, */ 1990 /* but the ultimate target may not have what we looked for */ 1991 h_errno = ntohs(hp->ancount) > 0? NO_DATA : NO_RECOVERY; 1992 return NULL; 1993 } 1994 1995 #define SORTEDADDR(p) (((struct sockaddr_in *)(void *)(p->ai_next->ai_addr))->sin_addr.s_addr) 1996 #define SORTMATCH(p, s) ((SORTEDADDR(p) & (s).mask) == (s).addr.s_addr) 1997 1998 static void 1999 aisort(struct addrinfo *s, res_state res) 2000 { 2001 struct addrinfo head, *t, *p; 2002 int i; 2003 2004 head.ai_next = NULL; 2005 t = &head; 2006 2007 for (i = 0; i < res->nsort; i++) { 2008 p = s; 2009 while (p->ai_next) { 2010 if ((p->ai_next->ai_family != AF_INET) 2011 || SORTMATCH(p, res->sort_list[i])) { 2012 t->ai_next = p->ai_next; 2013 t = t->ai_next; 2014 p->ai_next = p->ai_next->ai_next; 2015 } else { 2016 p = p->ai_next; 2017 } 2018 } 2019 } 2020 2021 /* add rest of list and reset s to the new list*/ 2022 t->ai_next = s->ai_next; 2023 s->ai_next = head.ai_next; 2024 } 2025 2026 static struct addrinfo * 2027 _dns_query(struct res_target *q, const struct addrinfo *pai, 2028 res_state res, int dosearch) 2029 { 2030 struct res_target *q2 = q->next; 2031 querybuf *buf, *buf2; 2032 struct addrinfo sentinel, *cur, *ai; 2033 2034 #ifdef DNS_DEBUG 2035 struct res_target *iter; 2036 for (iter = q; iter; iter = iter->next) 2037 printf("Query type %d for %s\n", iter->qtype, iter->name); 2038 #endif 2039 2040 buf = malloc(sizeof(*buf)); 2041 if (buf == NULL) { 2042 h_errno = NETDB_INTERNAL; 2043 return NULL; 2044 } 2045 buf2 = malloc(sizeof(*buf2)); 2046 if (buf2 == NULL) { 2047 free(buf); 2048 h_errno = NETDB_INTERNAL; 2049 return NULL; 2050 } 2051 2052 memset(&sentinel, 0, sizeof(sentinel)); 2053 cur = &sentinel; 2054 2055 q->answer = buf->buf; 2056 q->anslen = sizeof(buf->buf); 2057 if (q2) { 2058 q2->answer = buf2->buf; 2059 q2->anslen = sizeof(buf2->buf); 2060 } 2061 2062 if (dosearch) { 2063 if (res_searchN(q->name, q, res) < 0) 2064 goto out; 2065 } else { 2066 if (res_queryN(q->name, q, res) < 0) 2067 goto out; 2068 } 2069 2070 ai = getanswer(res, buf, q->n, q->name, q->qtype, pai); 2071 if (ai) { 2072 cur->ai_next = ai; 2073 while (cur && cur->ai_next) 2074 cur = cur->ai_next; 2075 } 2076 if (q2) { 2077 ai = getanswer(res, buf2, q2->n, q2->name, q2->qtype, pai); 2078 if (ai) 2079 cur->ai_next = ai; 2080 } 2081 free(buf); 2082 free(buf2); 2083 return sentinel.ai_next; 2084 out: 2085 free(buf); 2086 free(buf2); 2087 return NULL; 2088 } 2089 2090 /*ARGSUSED*/ 2091 static struct addrinfo * 2092 _dns_srv_lookup(const char *name, const char *servname, 2093 const struct addrinfo *pai) 2094 { 2095 static const char * const srvprotos[] = { "tcp", "udp" }; 2096 static const int srvnottype[] = { SOCK_DGRAM, SOCK_STREAM }; 2097 static const int nsrvprotos = 2; 2098 struct addrinfo sentinel, *cur, *ai; 2099 struct servent *serv, sv; 2100 struct servent_data svd; 2101 struct res_target q; 2102 res_state res; 2103 char *tname; 2104 int i; 2105 2106 res = __res_get_state(); 2107 if (res == NULL) 2108 return NULL; 2109 2110 memset(&svd, 0, sizeof(svd)); 2111 memset(&sentinel, 0, sizeof(sentinel)); 2112 cur = &sentinel; 2113 2114 /* 2115 * Iterate over supported SRV protocols. 2116 * (currently UDP and TCP only) 2117 */ 2118 for (i = 0; i < nsrvprotos; i++) { 2119 /* 2120 * Check that the caller didn't specify a hint 2121 * which precludes this protocol. 2122 */ 2123 if (pai->ai_socktype == srvnottype[i]) 2124 continue; 2125 /* 2126 * If the caller specified a port, 2127 * then lookup the database for the 2128 * official service name. 2129 */ 2130 serv = getservbyname_r(servname, srvprotos[i], &sv, &svd); 2131 if (serv == NULL) 2132 continue; 2133 2134 /* 2135 * Construct service DNS name. 2136 */ 2137 if (asprintf(&tname, "_%s._%s.%s", serv->s_name, serv->s_proto, 2138 name) < 0) 2139 continue; 2140 2141 memset(&q, 0, sizeof(q)); 2142 q.name = tname; 2143 q.qclass = C_IN; 2144 q.qtype = T_SRV; 2145 2146 /* 2147 * Do SRV query. 2148 */ 2149 ai = _dns_query(&q, pai, res, 1); 2150 if (ai) { 2151 cur->ai_next = ai; 2152 while (cur && cur->ai_next) 2153 cur = cur->ai_next; 2154 } 2155 free(tname); 2156 } 2157 2158 if (res->nsort) 2159 aisort(&sentinel, res); 2160 2161 __res_put_state(res); 2162 2163 return sentinel.ai_next; 2164 } 2165 2166 /*ARGSUSED*/ 2167 static struct addrinfo * 2168 _dns_host_lookup(const char *name, const struct addrinfo *pai) 2169 { 2170 struct res_target q, q2; 2171 struct addrinfo sentinel, *ai; 2172 res_state res; 2173 2174 res = __res_get_state(); 2175 if (res == NULL) 2176 return NULL; 2177 2178 memset(&q, 0, sizeof(q2)); 2179 memset(&q2, 0, sizeof(q2)); 2180 2181 switch (pai->ai_family) { 2182 case AF_UNSPEC: 2183 /* prefer IPv6 */ 2184 q.name = name; 2185 q.qclass = C_IN; 2186 q.qtype = T_AAAA; 2187 q.next = &q2; 2188 q2.name = name; 2189 q2.qclass = C_IN; 2190 q2.qtype = T_A; 2191 break; 2192 case AF_INET: 2193 q.name = name; 2194 q.qclass = C_IN; 2195 q.qtype = T_A; 2196 break; 2197 case AF_INET6: 2198 q.name = name; 2199 q.qclass = C_IN; 2200 q.qtype = T_AAAA; 2201 break; 2202 default: 2203 __res_put_state(res); 2204 h_errno = NETDB_INTERNAL; 2205 return NULL; 2206 } 2207 2208 ai = _dns_query(&q, pai, res, 1); 2209 2210 memset(&sentinel, 0, sizeof(sentinel)); 2211 sentinel.ai_next = ai; 2212 2213 if (ai != NULL && res->nsort) 2214 aisort(&sentinel, res); 2215 2216 __res_put_state(res); 2217 2218 return sentinel.ai_next; 2219 } 2220 2221 /*ARGSUSED*/ 2222 static int 2223 _dns_getaddrinfo(void *rv, void *cb_data, va_list ap) 2224 { 2225 struct addrinfo *ai = NULL; 2226 const char *name, *servname; 2227 const struct addrinfo *pai; 2228 2229 name = va_arg(ap, char *); 2230 pai = va_arg(ap, const struct addrinfo *); 2231 servname = va_arg(ap, char *); 2232 2233 /* 2234 * Try doing SRV lookup on service first. 2235 */ 2236 if (servname 2237 #ifdef AI_SRV 2238 && (pai->ai_flags & AI_SRV) 2239 #endif 2240 && !(pai->ai_flags & AI_NUMERICSERV) 2241 && str2number(servname) == -1) { 2242 2243 #ifdef DNS_DEBUG 2244 printf("%s: try SRV lookup\n", __func__); 2245 #endif 2246 ai = _dns_srv_lookup(name, servname, pai); 2247 } 2248 2249 /* 2250 * Do lookup on name. 2251 */ 2252 if (ai == NULL) { 2253 2254 #ifdef DNS_DEBUG 2255 printf("%s: try HOST lookup\n", __func__); 2256 #endif 2257 ai = _dns_host_lookup(name, pai); 2258 2259 if (ai == NULL) { 2260 switch (h_errno) { 2261 case HOST_NOT_FOUND: 2262 case NO_DATA: // XXX: Perhaps we could differentiate 2263 // So that we could return EAI_NODATA? 2264 return NS_NOTFOUND; 2265 case TRY_AGAIN: 2266 return NS_TRYAGAIN; 2267 default: 2268 return NS_UNAVAIL; 2269 } 2270 } 2271 } 2272 2273 *((struct addrinfo **)rv) = ai; 2274 return NS_SUCCESS; 2275 } 2276 2277 static void 2278 _sethtent(FILE **hostf) 2279 { 2280 2281 if (!*hostf) 2282 *hostf = fopen(_PATH_HOSTS, "re"); 2283 else 2284 rewind(*hostf); 2285 } 2286 2287 static void 2288 _endhtent(FILE **hostf) 2289 { 2290 2291 if (*hostf) { 2292 (void) fclose(*hostf); 2293 *hostf = NULL; 2294 } 2295 } 2296 2297 static struct addrinfo * 2298 _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2299 { 2300 char *p; 2301 char *cp, *tname, *cname; 2302 struct addrinfo hints, *res0, *res; 2303 int error; 2304 const char *addr; 2305 char hostbuf[8*1024]; 2306 2307 _DIAGASSERT(name != NULL); 2308 _DIAGASSERT(pai != NULL); 2309 2310 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "re"))) 2311 return NULL; 2312 again: 2313 if (!(p = fgets(hostbuf, (int)sizeof hostbuf, *hostf))) 2314 return NULL; 2315 if (*p == '#') 2316 goto again; 2317 if (!(cp = strpbrk(p, "#\n"))) 2318 goto again; 2319 *cp = '\0'; 2320 if (!(cp = strpbrk(p, " \t"))) 2321 goto again; 2322 *cp++ = '\0'; 2323 addr = p; 2324 /* if this is not something we're looking for, skip it. */ 2325 cname = NULL; 2326 while (cp && *cp) { 2327 if (*cp == ' ' || *cp == '\t') { 2328 cp++; 2329 continue; 2330 } 2331 if (!cname) 2332 cname = cp; 2333 tname = cp; 2334 if ((cp = strpbrk(cp, " \t")) != NULL) 2335 *cp++ = '\0'; 2336 if (strcasecmp(name, tname) == 0) 2337 goto found; 2338 } 2339 goto again; 2340 2341 found: 2342 hints = *pai; 2343 hints.ai_flags = AI_NUMERICHOST; 2344 error = getaddrinfo(addr, NULL, &hints, &res0); 2345 if (error) 2346 goto again; 2347 for (res = res0; res; res = res->ai_next) { 2348 /* cover it up */ 2349 res->ai_flags = pai->ai_flags; 2350 2351 if (pai->ai_flags & AI_CANONNAME) { 2352 if (get_canonname(pai, res, cname) != 0) { 2353 freeaddrinfo(res0); 2354 goto again; 2355 } 2356 } 2357 } 2358 return res0; 2359 } 2360 2361 /*ARGSUSED*/ 2362 static int 2363 _files_getaddrinfo(void *rv, void *cb_data, va_list ap) 2364 { 2365 const char *name; 2366 const struct addrinfo *pai; 2367 struct addrinfo sentinel, *cur; 2368 struct addrinfo *p; 2369 #ifndef _REENTRANT 2370 static 2371 #endif 2372 FILE *hostf = NULL; 2373 2374 name = va_arg(ap, char *); 2375 pai = va_arg(ap, const struct addrinfo *); 2376 2377 memset(&sentinel, 0, sizeof(sentinel)); 2378 cur = &sentinel; 2379 2380 _sethtent(&hostf); 2381 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2382 cur->ai_next = p; 2383 while (cur && cur->ai_next) 2384 cur = cur->ai_next; 2385 } 2386 _endhtent(&hostf); 2387 2388 *((struct addrinfo **)rv) = sentinel.ai_next; 2389 if (sentinel.ai_next == NULL) 2390 return NS_NOTFOUND; 2391 return NS_SUCCESS; 2392 } 2393 2394 #ifdef YP 2395 /*ARGSUSED*/ 2396 static struct addrinfo * 2397 _yphostent(char *line, const struct addrinfo *pai) 2398 { 2399 struct addrinfo sentinel, *cur; 2400 struct addrinfo hints, *res, *res0; 2401 int error; 2402 char *p; 2403 const char *addr, *canonname; 2404 char *nextline; 2405 char *cp; 2406 2407 _DIAGASSERT(line != NULL); 2408 _DIAGASSERT(pai != NULL); 2409 2410 p = line; 2411 addr = canonname = NULL; 2412 2413 memset(&sentinel, 0, sizeof(sentinel)); 2414 cur = &sentinel; 2415 2416 nextline: 2417 /* terminate line */ 2418 cp = strchr(p, '\n'); 2419 if (cp) { 2420 *cp++ = '\0'; 2421 nextline = cp; 2422 } else 2423 nextline = NULL; 2424 2425 cp = strpbrk(p, " \t"); 2426 if (cp == NULL) { 2427 if (canonname == NULL) 2428 return NULL; 2429 else 2430 goto done; 2431 } 2432 *cp++ = '\0'; 2433 2434 addr = p; 2435 2436 while (cp && *cp) { 2437 if (*cp == ' ' || *cp == '\t') { 2438 cp++; 2439 continue; 2440 } 2441 if (!canonname) 2442 canonname = cp; 2443 if ((cp = strpbrk(cp, " \t")) != NULL) 2444 *cp++ = '\0'; 2445 } 2446 2447 hints = *pai; 2448 hints.ai_flags = AI_NUMERICHOST; 2449 error = getaddrinfo(addr, NULL, &hints, &res0); 2450 if (error == 0) { 2451 for (res = res0; res; res = res->ai_next) { 2452 /* cover it up */ 2453 res->ai_flags = pai->ai_flags; 2454 2455 if (pai->ai_flags & AI_CANONNAME) 2456 (void)get_canonname(pai, res, canonname); 2457 } 2458 } else 2459 res0 = NULL; 2460 if (res0) { 2461 cur->ai_next = res0; 2462 while (cur->ai_next) 2463 cur = cur->ai_next; 2464 } 2465 2466 if (nextline) { 2467 p = nextline; 2468 goto nextline; 2469 } 2470 2471 done: 2472 return sentinel.ai_next; 2473 } 2474 2475 /*ARGSUSED*/ 2476 static int 2477 _yp_getaddrinfo(void *rv, void *cb_data, va_list ap) 2478 { 2479 struct addrinfo sentinel, *cur; 2480 struct addrinfo *ai = NULL; 2481 char *ypbuf; 2482 int ypbuflen, r; 2483 const char *name; 2484 const struct addrinfo *pai; 2485 char *ypdomain; 2486 2487 if (_yp_check(&ypdomain) == 0) 2488 return NS_UNAVAIL; 2489 2490 name = va_arg(ap, char *); 2491 pai = va_arg(ap, const struct addrinfo *); 2492 2493 memset(&sentinel, 0, sizeof(sentinel)); 2494 cur = &sentinel; 2495 2496 /* hosts.byname is only for IPv4 (Solaris8) */ 2497 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2498 r = yp_match(ypdomain, "hosts.byname", name, 2499 (int)strlen(name), &ypbuf, &ypbuflen); 2500 if (r == 0) { 2501 struct addrinfo ai4; 2502 2503 ai4 = *pai; 2504 ai4.ai_family = AF_INET; 2505 ai = _yphostent(ypbuf, &ai4); 2506 if (ai) { 2507 cur->ai_next = ai; 2508 while (cur && cur->ai_next) 2509 cur = cur->ai_next; 2510 } 2511 } 2512 free(ypbuf); 2513 } 2514 2515 /* ipnodes.byname can hold both IPv4/v6 */ 2516 r = yp_match(ypdomain, "ipnodes.byname", name, 2517 (int)strlen(name), &ypbuf, &ypbuflen); 2518 if (r == 0) { 2519 ai = _yphostent(ypbuf, pai); 2520 if (ai) 2521 cur->ai_next = ai; 2522 free(ypbuf); 2523 } 2524 2525 if (sentinel.ai_next == NULL) { 2526 h_errno = HOST_NOT_FOUND; 2527 return NS_NOTFOUND; 2528 } 2529 *((struct addrinfo **)rv) = sentinel.ai_next; 2530 return NS_SUCCESS; 2531 } 2532 #endif 2533 2534 /* resolver logic */ 2535 2536 /* 2537 * Formulate a normal query, send, and await answer. 2538 * Returned answer is placed in supplied buffer "answer". 2539 * Perform preliminary check of answer, returning success only 2540 * if no error is indicated and the answer count is nonzero. 2541 * Return the size of the response on success, -1 on error. 2542 * Error number is left in h_errno. 2543 * 2544 * Caller must parse answer and determine whether it answers the question. 2545 */ 2546 static int 2547 res_queryN(const char *name, /* domain name */ struct res_target *target, 2548 res_state statp) 2549 { 2550 u_char buf[MAXPACKET]; 2551 HEADER *hp; 2552 int n; 2553 struct res_target *t; 2554 int rcode; 2555 u_char *rdata; 2556 int ancount; 2557 2558 _DIAGASSERT(name != NULL); 2559 /* XXX: target may be NULL??? */ 2560 2561 rcode = NOERROR; 2562 ancount = 0; 2563 2564 for (t = target; t; t = t->next) { 2565 int class, type; 2566 u_char *answer; 2567 int anslen; 2568 u_int oflags; 2569 2570 hp = (HEADER *)(void *)t->answer; 2571 oflags = statp->_flags; 2572 2573 again: 2574 hp->rcode = NOERROR; /* default */ 2575 2576 /* make it easier... */ 2577 class = t->qclass; 2578 type = t->qtype; 2579 answer = t->answer; 2580 anslen = t->anslen; 2581 #ifdef DEBUG 2582 if (statp->options & RES_DEBUG) 2583 printf(";; res_nquery(%s, %d, %d)\n", name, class, type); 2584 #endif 2585 2586 n = res_nmkquery(statp, QUERY, name, class, type, NULL, 0, NULL, 2587 buf, (int)sizeof(buf)); 2588 #ifdef RES_USE_EDNS0 2589 if (n > 0 && (statp->_flags & RES_F_EDNS0ERR) == 0 && 2590 (statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0) { 2591 n = res_nopt(statp, n, buf, (int)sizeof(buf), anslen); 2592 rdata = &buf[n]; 2593 if (n > 0 && (statp->options & RES_NSID) != 0U) { 2594 n = res_nopt_rdata(statp, n, buf, 2595 (int)sizeof(buf), 2596 rdata, NS_OPT_NSID, 0, NULL); 2597 } 2598 } 2599 #endif 2600 if (n <= 0) { 2601 #ifdef DEBUG 2602 if (statp->options & RES_DEBUG) 2603 printf(";; res_nquery: mkquery failed\n"); 2604 #endif 2605 h_errno = NO_RECOVERY; 2606 return n; 2607 } 2608 n = res_nsend(statp, buf, n, answer, anslen); 2609 if (n < 0) { 2610 #ifdef RES_USE_EDNS0 2611 /* if the query choked with EDNS0, retry without EDNS0 */ 2612 if ((statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U && 2613 ((oflags ^ statp->_flags) & RES_F_EDNS0ERR) != 0) { 2614 statp->_flags |= RES_F_EDNS0ERR; 2615 if (statp->options & RES_DEBUG) 2616 printf(";; res_nquery: retry without EDNS0\n"); 2617 goto again; 2618 } 2619 #endif 2620 #if 0 2621 #ifdef DEBUG 2622 if (statp->options & RES_DEBUG) 2623 printf(";; res_query: send error\n"); 2624 #endif 2625 h_errno = TRY_AGAIN; 2626 return n; 2627 #endif 2628 } 2629 2630 if (n < 0 || hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2631 rcode = hp->rcode; /* record most recent error */ 2632 #ifdef DEBUG 2633 if (statp->options & RES_DEBUG) 2634 printf(";; rcode = (%s), counts = an:%d ns:%d ar:%d\n", 2635 p_rcode(hp->rcode), 2636 ntohs(hp->ancount), 2637 ntohs(hp->nscount), 2638 ntohs(hp->arcount)); 2639 #endif 2640 continue; 2641 } 2642 2643 ancount += ntohs(hp->ancount); 2644 2645 t->n = n; 2646 } 2647 2648 if (ancount == 0) { 2649 switch (rcode) { 2650 case NXDOMAIN: 2651 h_errno = HOST_NOT_FOUND; 2652 break; 2653 case SERVFAIL: 2654 h_errno = TRY_AGAIN; 2655 break; 2656 case NOERROR: 2657 h_errno = NO_DATA; 2658 break; 2659 case FORMERR: 2660 case NOTIMP: 2661 case REFUSED: 2662 default: 2663 h_errno = NO_RECOVERY; 2664 break; 2665 } 2666 return -1; 2667 } 2668 return ancount; 2669 } 2670 2671 /* 2672 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2673 * Return the size of the response on success, -1 on error. 2674 * If enabled, implement search rules until answer or unrecoverable failure 2675 * is detected. Error code, if any, is left in h_errno. 2676 */ 2677 static int 2678 res_searchN(const char *name, struct res_target *target, res_state res) 2679 { 2680 const char *cp, * const *domain; 2681 HEADER *hp; 2682 u_int dots; 2683 char buf[MAXHOSTNAMELEN]; 2684 int trailing_dot, ret, saved_herrno; 2685 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 2686 2687 _DIAGASSERT(name != NULL); 2688 _DIAGASSERT(target != NULL); 2689 2690 hp = (HEADER *)(void *)target->answer; /*XXX*/ 2691 2692 errno = 0; 2693 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 2694 dots = 0; 2695 for (cp = name; *cp; cp++) 2696 dots += (*cp == '.'); 2697 trailing_dot = 0; 2698 if (cp > name && *--cp == '.') 2699 trailing_dot++; 2700 2701 /* 2702 * if there aren't any dots, it could be a user-level alias 2703 */ 2704 if (!dots && (cp = res_hostalias(res, name, buf, sizeof(buf))) != NULL) { 2705 ret = res_queryN(cp, target, res); 2706 return ret; 2707 } 2708 2709 /* 2710 * If there are dots in the name already, let's just give it a try 2711 * 'as is'. The threshold can be set with the "ndots" option. 2712 */ 2713 saved_herrno = -1; 2714 if (dots >= res->ndots) { 2715 ret = res_querydomainN(name, NULL, target, res); 2716 if (ret > 0) 2717 return ret; 2718 saved_herrno = h_errno; 2719 tried_as_is++; 2720 } 2721 2722 /* 2723 * We do at least one level of search if 2724 * - there is no dot and RES_DEFNAME is set, or 2725 * - there is at least one dot, there is no trailing dot, 2726 * and RES_DNSRCH is set. 2727 */ 2728 if ((!dots && (res->options & RES_DEFNAMES)) || 2729 (dots && !trailing_dot && (res->options & RES_DNSRCH))) { 2730 int done = 0; 2731 2732 for (domain = (const char * const *)res->dnsrch; 2733 *domain && !done; 2734 domain++) { 2735 2736 ret = res_querydomainN(name, *domain, target, res); 2737 if (ret > 0) 2738 return ret; 2739 2740 /* 2741 * If no server present, give up. 2742 * If name isn't found in this domain, 2743 * keep trying higher domains in the search list 2744 * (if that's enabled). 2745 * On a NO_DATA error, keep trying, otherwise 2746 * a wildcard entry of another type could keep us 2747 * from finding this entry higher in the domain. 2748 * If we get some other error (negative answer or 2749 * server failure), then stop searching up, 2750 * but try the input name below in case it's 2751 * fully-qualified. 2752 */ 2753 if (errno == ECONNREFUSED) { 2754 h_errno = TRY_AGAIN; 2755 return -1; 2756 } 2757 2758 switch (h_errno) { 2759 case NO_DATA: 2760 got_nodata++; 2761 /* FALLTHROUGH */ 2762 case HOST_NOT_FOUND: 2763 /* keep trying */ 2764 break; 2765 case TRY_AGAIN: 2766 if (hp->rcode == SERVFAIL) { 2767 /* try next search element, if any */ 2768 got_servfail++; 2769 break; 2770 } 2771 /* FALLTHROUGH */ 2772 default: 2773 /* anything else implies that we're done */ 2774 done++; 2775 } 2776 /* 2777 * if we got here for some reason other than DNSRCH, 2778 * we only wanted one iteration of the loop, so stop. 2779 */ 2780 if (!(res->options & RES_DNSRCH)) 2781 done++; 2782 } 2783 } 2784 2785 /* 2786 * if we have not already tried the name "as is", do that now. 2787 * note that we do this regardless of how many dots were in the 2788 * name or whether it ends with a dot. 2789 */ 2790 if (!tried_as_is) { 2791 ret = res_querydomainN(name, NULL, target, res); 2792 if (ret > 0) 2793 return ret; 2794 } 2795 2796 /* 2797 * if we got here, we didn't satisfy the search. 2798 * if we did an initial full query, return that query's h_errno 2799 * (note that we wouldn't be here if that query had succeeded). 2800 * else if we ever got a nodata, send that back as the reason. 2801 * else send back meaningless h_errno, that being the one from 2802 * the last DNSRCH we did. 2803 */ 2804 if (saved_herrno != -1) 2805 h_errno = saved_herrno; 2806 else if (got_nodata) 2807 h_errno = NO_DATA; 2808 else if (got_servfail) 2809 h_errno = TRY_AGAIN; 2810 return -1; 2811 } 2812 2813 /* 2814 * Perform a call on res_query on the concatenation of name and domain, 2815 * removing a trailing dot from name if domain is NULL. 2816 */ 2817 static int 2818 res_querydomainN(const char *name, const char *domain, 2819 struct res_target *target, res_state res) 2820 { 2821 char nbuf[MAXDNAME]; 2822 const char *longname = nbuf; 2823 size_t n; 2824 2825 _DIAGASSERT(name != NULL); 2826 /* XXX: target may be NULL??? */ 2827 2828 #ifdef DEBUG 2829 if (res->options & RES_DEBUG) 2830 printf(";; res_querydomain(%s, %s)\n", 2831 name, domain?domain:"<Nil>"); 2832 #endif 2833 if (domain == NULL) { 2834 /* 2835 * Check for trailing '.'; 2836 * copy without '.' if present. 2837 */ 2838 n = strlen(name); 2839 if (n + 1 > sizeof(nbuf)) { 2840 h_errno = NO_RECOVERY; 2841 return -1; 2842 } 2843 if (n > 0 && name[--n] == '.') { 2844 snprintf(nbuf, sizeof(nbuf), "%*s", (int)n, name); 2845 } else 2846 longname = name; 2847 } else { 2848 if ((size_t)snprintf(nbuf, sizeof(nbuf), "%s.%s", 2849 name, domain) >= sizeof(nbuf)) { 2850 h_errno = NO_RECOVERY; 2851 return -1; 2852 } 2853 } 2854 return res_queryN(longname, target, res); 2855 } 2856 2857 #ifdef TEST 2858 int 2859 main(int argc, char *argv[]) { 2860 struct addrinfo *ai, *sai; 2861 int i, e; 2862 char buf[1024]; 2863 2864 for (i = 1; i < argc; i++) { 2865 if ((e = getaddrinfo(argv[i], NULL, NULL, &sai)) != 0) 2866 warnx("%s: %s", argv[i], gai_strerror(e)); 2867 for (ai = sai; ai; ai = ai->ai_next) { 2868 sockaddr_snprintf(buf, sizeof(buf), "%a", ai->ai_addr); 2869 printf("flags=0x%x family=%d socktype=%d protocol=%d " 2870 "addrlen=%zu addr=%s canonname=%s next=%p\n", 2871 ai->ai_flags, 2872 ai->ai_family, 2873 ai->ai_socktype, 2874 ai->ai_protocol, 2875 (size_t)ai->ai_addrlen, 2876 buf, 2877 ai->ai_canonname, 2878 ai->ai_next); 2879 } 2880 if (sai) 2881 freeaddrinfo(sai); 2882 } 2883 return 0; 2884 } 2885 #endif 2886