1 /* $NetBSD: getaddrinfo.c,v 1.116 2017/09/29 00:04:33 christos 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 (alows 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 1.116 2017/09/29 00:04:33 christos 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 nor servname 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 (/*CONSTCOND*/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 (/*CONSTCOND*/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 (/*CONSTCOND*/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 (/*CONSTCOND*/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 = malloc(sizeof(*aio) * n)) == NULL) 721 return n; /* give up reordering */ 722 memset(aio, 0, sizeof(*aio) * n); 723 724 /* retrieve address selection policy from the kernel */ 725 TAILQ_INIT(&policyhead); 726 if (!get_addrselectpolicy(&policyhead)) { 727 /* no policy is installed into kernel, we don't sort. */ 728 free(aio); 729 return n; 730 } 731 732 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 733 aio[i].aio_ai = ai; 734 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 735 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 736 &policyhead); 737 set_source(&aio[i], &policyhead, svd); 738 } 739 740 /* perform sorting. */ 741 qsort(aio, n, sizeof(*aio), comp_dst); 742 743 /* reorder the addrinfo chain. */ 744 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 745 *aip = aio[i].aio_ai; 746 aip = &aio[i].aio_ai->ai_next; 747 } 748 *aip = NULL; 749 750 /* cleanup and return */ 751 free(aio); 752 free_addrselectpolicy(&policyhead); 753 return n; 754 } 755 756 static int 757 get_addrselectpolicy(struct policyhead *head) 758 { 759 #ifdef INET6 760 static const int mib[] = { 761 CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 762 static const u_int miblen = (u_int)__arraycount(mib); 763 size_t l; 764 char *buf; 765 struct in6_addrpolicy *pol, *ep; 766 767 if (sysctl(mib, miblen, NULL, &l, NULL, 0) < 0) 768 return 0; 769 if (l == 0) 770 return 0; 771 if ((buf = malloc(l)) == NULL) 772 return 0; 773 if (sysctl(mib, miblen, buf, &l, NULL, 0) < 0) { 774 free(buf); 775 return 0; 776 } 777 778 ep = (void *)(buf + l); 779 for (pol = (void *)buf; pol + 1 <= ep; pol++) { 780 struct policyqueue *new; 781 782 if ((new = malloc(sizeof(*new))) == NULL) { 783 free_addrselectpolicy(head); /* make the list empty */ 784 break; 785 } 786 new->pc_policy = *pol; 787 TAILQ_INSERT_TAIL(head, new, pc_entry); 788 } 789 790 free(buf); 791 return 1; 792 #else 793 return 0; 794 #endif 795 } 796 797 static void 798 free_addrselectpolicy(struct policyhead *head) 799 { 800 struct policyqueue *ent, *nent; 801 802 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 803 nent = TAILQ_NEXT(ent, pc_entry); 804 TAILQ_REMOVE(head, ent, pc_entry); 805 free(ent); 806 } 807 } 808 809 static struct policyqueue * 810 match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 811 { 812 #ifdef INET6 813 struct policyqueue *ent, *bestent = NULL; 814 struct in6_addrpolicy *pol; 815 int curmatchlen, bestmatchlen = -1; 816 u_char *mp, *ep, *k, *p; 817 u_int m; 818 struct sockaddr_in6 key; 819 820 switch(addr->sa_family) { 821 case AF_INET6: 822 memcpy(&key, addr, sizeof(key)); 823 break; 824 case AF_INET: 825 /* convert the address into IPv4-mapped IPv6 address. */ 826 memset(&key, 0, sizeof(key)); 827 key.sin6_family = AF_INET6; 828 key.sin6_len = sizeof(key); 829 key.sin6_addr.s6_addr[10] = 0xff; 830 key.sin6_addr.s6_addr[11] = 0xff; 831 memcpy(&key.sin6_addr.s6_addr[12], sa4addr(addr), 4); 832 break; 833 default: 834 return NULL; 835 } 836 837 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 838 pol = &ent->pc_policy; 839 curmatchlen = 0; 840 841 mp = (void *)&pol->addrmask.sin6_addr; 842 ep = mp + 16; /* XXX: scope field? */ 843 k = (void *)&key.sin6_addr; 844 p = (void *)&pol->addr.sin6_addr; 845 for (; mp < ep && *mp; mp++, k++, p++) { 846 m = *mp; 847 if ((*k & m) != *p) 848 goto next; /* not match */ 849 if (m == 0xff) /* short cut for a typical case */ 850 curmatchlen += 8; 851 else { 852 while (m >= 0x80) { 853 curmatchlen++; 854 m <<= 1; 855 } 856 } 857 } 858 859 /* matched. check if this is better than the current best. */ 860 if (curmatchlen > bestmatchlen) { 861 bestent = ent; 862 bestmatchlen = curmatchlen; 863 } 864 865 next: 866 continue; 867 } 868 869 return bestent; 870 #else 871 return NULL; 872 #endif 873 874 } 875 876 static void 877 set_source(struct ai_order *aio, struct policyhead *ph, 878 struct servent_data *svd) 879 { 880 struct addrinfo ai = *aio->aio_ai; 881 struct sockaddr_storage ss; 882 socklen_t srclen; 883 int s; 884 885 /* set unspec ("no source is available"), just in case */ 886 aio->aio_srcsa.sa_family = AF_UNSPEC; 887 aio->aio_srcscope = -1; 888 889 switch(ai.ai_family) { 890 case AF_INET: 891 #ifdef INET6 892 case AF_INET6: 893 #endif 894 break; 895 default: /* ignore unsupported AFs explicitly */ 896 return; 897 } 898 899 /* XXX: make a dummy addrinfo to call connect() */ 900 ai.ai_socktype = SOCK_DGRAM; 901 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 902 ai.ai_next = NULL; 903 memset(&ss, 0, sizeof(ss)); 904 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 905 ai.ai_addr = (void *)&ss; 906 get_port(&ai, "1", 0, svd); 907 908 /* open a socket to get the source address for the given dst */ 909 if ((s = socket(ai.ai_family, ai.ai_socktype | SOCK_CLOEXEC, 910 ai.ai_protocol)) < 0) 911 return; /* give up */ 912 if (connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 913 goto cleanup; 914 srclen = ai.ai_addrlen; 915 if (getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 916 aio->aio_srcsa.sa_family = AF_UNSPEC; 917 goto cleanup; 918 } 919 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 920 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 921 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 922 #ifdef INET6 923 if (ai.ai_family == AF_INET6) { 924 struct in6_ifreq ifr6; 925 u_int32_t flags6; 926 927 memset(&ifr6, 0, sizeof(ifr6)); 928 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 929 if (ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 930 flags6 = ifr6.ifr_ifru.ifru_flags6; 931 if ((flags6 & IN6_IFF_DEPRECATED)) 932 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 933 } 934 } 935 #endif 936 937 cleanup: 938 close(s); 939 return; 940 } 941 942 static int 943 matchlen(struct sockaddr *src, struct sockaddr *dst) 944 { 945 int match = 0; 946 u_char *s, *d; 947 u_char *lim; 948 u_int r, addrlen; 949 950 switch (src->sa_family) { 951 #ifdef INET6 952 case AF_INET6: 953 s = sa6addr(src); 954 d = sa6addr(dst); 955 addrlen = sizeof(struct in6_addr); 956 lim = s + addrlen; 957 break; 958 #endif 959 case AF_INET: 960 s = sa4addr(src); 961 d = sa4addr(dst); 962 addrlen = sizeof(struct in_addr); 963 lim = s + addrlen; 964 break; 965 default: 966 return 0; 967 } 968 969 while (s < lim) 970 if ((r = (*d++ ^ *s++)) != 0) { 971 while (r < addrlen * 8) { 972 match++; 973 r <<= 1; 974 } 975 break; 976 } else 977 match += 8; 978 return match; 979 } 980 981 static int 982 comp_dst(const void *arg1, const void *arg2) 983 { 984 const struct ai_order *dst1 = arg1, *dst2 = arg2; 985 986 /* 987 * Rule 1: Avoid unusable destinations. 988 * XXX: we currently do not consider if an appropriate route exists. 989 */ 990 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 991 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 992 return -1; 993 } 994 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 995 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 996 return 1; 997 } 998 999 /* Rule 2: Prefer matching scope. */ 1000 if (dst1->aio_dstscope == dst1->aio_srcscope && 1001 dst2->aio_dstscope != dst2->aio_srcscope) { 1002 return -1; 1003 } 1004 if (dst1->aio_dstscope != dst1->aio_srcscope && 1005 dst2->aio_dstscope == dst2->aio_srcscope) { 1006 return 1; 1007 } 1008 1009 /* Rule 3: Avoid deprecated addresses. */ 1010 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 1011 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 1012 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 1013 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 1014 return -1; 1015 } 1016 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 1017 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 1018 return 1; 1019 } 1020 } 1021 1022 /* Rule 4: Prefer home addresses. */ 1023 /* XXX: not implemented yet */ 1024 1025 /* Rule 5: Prefer matching label. */ 1026 #ifdef INET6 1027 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 1028 dst1->aio_srcpolicy->pc_policy.label == 1029 dst1->aio_dstpolicy->pc_policy.label && 1030 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 1031 dst2->aio_srcpolicy->pc_policy.label != 1032 dst2->aio_dstpolicy->pc_policy.label)) { 1033 return -1; 1034 } 1035 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 1036 dst2->aio_srcpolicy->pc_policy.label == 1037 dst2->aio_dstpolicy->pc_policy.label && 1038 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 1039 dst1->aio_srcpolicy->pc_policy.label != 1040 dst1->aio_dstpolicy->pc_policy.label)) { 1041 return 1; 1042 } 1043 #endif 1044 1045 /* Rule 6: Prefer higher precedence. */ 1046 #ifdef INET6 1047 if (dst1->aio_dstpolicy && 1048 (dst2->aio_dstpolicy == NULL || 1049 dst1->aio_dstpolicy->pc_policy.preced > 1050 dst2->aio_dstpolicy->pc_policy.preced)) { 1051 return -1; 1052 } 1053 if (dst2->aio_dstpolicy && 1054 (dst1->aio_dstpolicy == NULL || 1055 dst2->aio_dstpolicy->pc_policy.preced > 1056 dst1->aio_dstpolicy->pc_policy.preced)) { 1057 return 1; 1058 } 1059 #endif 1060 1061 /* Rule 7: Prefer native transport. */ 1062 /* XXX: not implemented yet */ 1063 1064 /* Rule 8: Prefer smaller scope. */ 1065 if (dst1->aio_dstscope >= 0 && 1066 dst1->aio_dstscope < dst2->aio_dstscope) { 1067 return -1; 1068 } 1069 if (dst2->aio_dstscope >= 0 && 1070 dst2->aio_dstscope < dst1->aio_dstscope) { 1071 return 1; 1072 } 1073 1074 /* 1075 * Rule 9: Use longest matching prefix. 1076 * We compare the match length in a same AF only. 1077 */ 1078 if (dst1->aio_ai->ai_addr->sa_family == 1079 dst2->aio_ai->ai_addr->sa_family && 1080 dst1->aio_ai->ai_addr->sa_family != AF_INET) { 1081 if (dst1->aio_matchlen > dst2->aio_matchlen) { 1082 return -1; 1083 } 1084 if (dst1->aio_matchlen < dst2->aio_matchlen) { 1085 return 1; 1086 } 1087 } 1088 1089 /* Rule 10: Otherwise, leave the order unchanged. */ 1090 return -1; 1091 } 1092 1093 /* 1094 * Copy from scope.c. 1095 * XXX: we should standardize the functions and link them as standard 1096 * library. 1097 */ 1098 static int 1099 gai_addr2scopetype(struct sockaddr *sa) 1100 { 1101 #ifdef INET6 1102 struct sockaddr_in6 *sa6; 1103 #endif 1104 struct sockaddr_in *sa4; 1105 u_char *p; 1106 1107 switch(sa->sa_family) { 1108 #ifdef INET6 1109 case AF_INET6: 1110 sa6 = (void *)sa; 1111 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1112 /* just use the scope field of the multicast address */ 1113 return sa6->sin6_addr.s6_addr[2] & 0x0f; 1114 } 1115 /* 1116 * Unicast addresses: map scope type to corresponding scope 1117 * value defined for multcast addresses. 1118 * XXX: hardcoded scope type values are bad... 1119 */ 1120 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1121 return 1; /* node local scope */ 1122 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1123 return 2; /* link-local scope */ 1124 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1125 return 5; /* site-local scope */ 1126 return 14; /* global scope */ 1127 #endif 1128 case AF_INET: 1129 /* 1130 * IPv4 pseudo scoping according to RFC 3484. 1131 */ 1132 sa4 = (void *)sa; 1133 p = (u_char *)(void *)&sa4->sin_addr; 1134 /* IPv4 autoconfiguration addresses have link-local scope. */ 1135 if (p[0] == 169 && p[1] == 254) 1136 return 2; 1137 /* Private addresses have site-local scope. */ 1138 if (p[0] == 10 || 1139 (p[0] == 172 && (p[1] & 0xf0) == 16) || 1140 (p[0] == 192 && p[1] == 168)) 1141 return 14; /* XXX: It should be 5 unless NAT */ 1142 /* Loopback addresses have link-local scope. */ 1143 if (p[0] == 127) 1144 return 2; 1145 return 14; 1146 default: 1147 errno = EAFNOSUPPORT; /* is this a good error? */ 1148 return -1; 1149 } 1150 } 1151 1152 /* 1153 * FQDN hostname, DNS lookup 1154 */ 1155 static int 1156 explore_fqdn(const struct addrinfo *pai, const char *hostname, 1157 const char *servname, struct addrinfo **res, struct servent_data *svd) 1158 { 1159 struct addrinfo *result; 1160 struct addrinfo *cur; 1161 int error = 0; 1162 static const ns_dtab dtab[] = { 1163 NS_FILES_CB(_files_getaddrinfo, NULL) 1164 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1165 NS_NIS_CB(_yp_getaddrinfo, NULL) 1166 NS_NULL_CB 1167 }; 1168 1169 _DIAGASSERT(pai != NULL); 1170 /* hostname may be NULL */ 1171 /* servname may be NULL */ 1172 _DIAGASSERT(res != NULL); 1173 1174 result = NULL; 1175 1176 /* 1177 * if the servname does not match socktype/protocol, ignore it. 1178 */ 1179 if (get_portmatch(pai, servname, svd) != 0) 1180 return 0; 1181 1182 switch (nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1183 default_dns_files, hostname, pai, servname)) { 1184 case NS_TRYAGAIN: 1185 error = EAI_AGAIN; 1186 goto free; 1187 case NS_UNAVAIL: 1188 error = EAI_FAIL; 1189 goto free; 1190 case NS_NOTFOUND: 1191 error = EAI_NONAME; 1192 goto free; 1193 case NS_SUCCESS: 1194 error = 0; 1195 for (cur = result; cur; cur = cur->ai_next) { 1196 /* Check for already filled port. */ 1197 if (*getport(cur)) 1198 continue; 1199 GET_PORT(cur, servname, svd); 1200 /* canonname should be filled already */ 1201 } 1202 break; 1203 } 1204 1205 *res = result; 1206 1207 return 0; 1208 1209 free: 1210 if (result) 1211 freeaddrinfo(result); 1212 return error; 1213 } 1214 1215 /* 1216 * hostname == NULL. 1217 * passive socket -> anyaddr (0.0.0.0 or ::) 1218 * non-passive socket -> localhost (127.0.0.1 or ::1) 1219 */ 1220 static int 1221 explore_null(const struct addrinfo *pai, const char *servname, 1222 struct addrinfo **res, struct servent_data *svd) 1223 { 1224 int s; 1225 const struct afd *afd; 1226 struct addrinfo *cur; 1227 struct addrinfo sentinel; 1228 int error; 1229 1230 _DIAGASSERT(pai != NULL); 1231 /* servname may be NULL */ 1232 _DIAGASSERT(res != NULL); 1233 1234 *res = NULL; 1235 sentinel.ai_next = NULL; 1236 cur = &sentinel; 1237 1238 /* 1239 * filter out AFs that are not supported by the kernel 1240 * XXX errno? 1241 */ 1242 s = socket(pai->ai_family, SOCK_DGRAM, 0); 1243 if (s < 0) { 1244 if (errno != EMFILE) 1245 return 0; 1246 } else 1247 close(s); 1248 1249 /* 1250 * if the servname does not match socktype/protocol, ignore it. 1251 */ 1252 if (get_portmatch(pai, servname, svd) != 0) 1253 return 0; 1254 1255 afd = find_afd(pai->ai_family); 1256 if (afd == NULL) 1257 return 0; 1258 1259 if (pai->ai_flags & AI_PASSIVE) { 1260 GET_AI(cur->ai_next, afd, afd->a_addrany); 1261 /* xxx meaningless? 1262 * GET_CANONNAME(cur->ai_next, "anyaddr"); 1263 */ 1264 GET_PORT(cur->ai_next, servname, svd); 1265 } else { 1266 GET_AI(cur->ai_next, afd, afd->a_loopback); 1267 /* xxx meaningless? 1268 * GET_CANONNAME(cur->ai_next, "localhost"); 1269 */ 1270 GET_PORT(cur->ai_next, servname, svd); 1271 } 1272 cur = cur->ai_next; 1273 1274 *res = sentinel.ai_next; 1275 return 0; 1276 1277 free: 1278 if (sentinel.ai_next) 1279 freeaddrinfo(sentinel.ai_next); 1280 return error; 1281 } 1282 1283 /* 1284 * numeric hostname 1285 */ 1286 static int 1287 explore_numeric(const struct addrinfo *pai, const char *hostname, 1288 const char *servname, struct addrinfo **res, const char *canonname, 1289 struct servent_data *svd) 1290 { 1291 const struct afd *afd; 1292 struct addrinfo *cur; 1293 struct addrinfo sentinel; 1294 int error; 1295 char pton[PTON_MAX]; 1296 1297 _DIAGASSERT(pai != NULL); 1298 /* hostname may be NULL */ 1299 /* servname may be NULL */ 1300 _DIAGASSERT(res != NULL); 1301 1302 *res = NULL; 1303 sentinel.ai_next = NULL; 1304 cur = &sentinel; 1305 1306 /* 1307 * if the servname does not match socktype/protocol, ignore it. 1308 */ 1309 if (get_portmatch(pai, servname, svd) != 0) 1310 return 0; 1311 1312 afd = find_afd(pai->ai_family); 1313 if (afd == NULL) 1314 return 0; 1315 1316 switch (afd->a_af) { 1317 case AF_INET: 1318 /* 1319 * RFC3493 section 6.1, requires getaddrinfo() to accept 1320 * AF_INET formats that are accepted by inet_addr(); here 1321 * we use the equivalent inet_aton() function so we can 1322 * check for errors. inet_pton() only accepts addresses 1323 * in the dotted quad format and only in base 10, so we 1324 * need to treat AF_INET specially. 1325 */ 1326 if (inet_aton(hostname, (void *)pton) == 1) { 1327 if (pai->ai_family == afd->a_af || 1328 pai->ai_family == PF_UNSPEC /*?*/) { 1329 GET_AI(cur->ai_next, afd, pton); 1330 GET_PORT(cur->ai_next, servname, svd); 1331 if ((pai->ai_flags & AI_CANONNAME)) { 1332 /* 1333 * Set the numeric address itself as 1334 * the canonical name, based on a 1335 * clarification in rfc2553bis-03. 1336 */ 1337 GET_CANONNAME(cur->ai_next, canonname); 1338 } 1339 while (cur && cur->ai_next) 1340 cur = cur->ai_next; 1341 } else 1342 ERR(EAI_FAMILY); /*xxx*/ 1343 } 1344 break; 1345 default: 1346 if (inet_pton(afd->a_af, hostname, pton) == 1) { 1347 if (pai->ai_family == afd->a_af || 1348 pai->ai_family == PF_UNSPEC /*?*/) { 1349 GET_AI(cur->ai_next, afd, pton); 1350 GET_PORT(cur->ai_next, servname, svd); 1351 if ((pai->ai_flags & AI_CANONNAME)) { 1352 /* 1353 * Set the numeric address itself as 1354 * the canonical name, based on a 1355 * clarification in rfc2553bis-03. 1356 */ 1357 GET_CANONNAME(cur->ai_next, canonname); 1358 } 1359 while (cur->ai_next) 1360 cur = cur->ai_next; 1361 } else 1362 ERR(EAI_FAMILY); /*xxx*/ 1363 } 1364 break; 1365 } 1366 1367 *res = sentinel.ai_next; 1368 return 0; 1369 1370 free: 1371 bad: 1372 if (sentinel.ai_next) 1373 freeaddrinfo(sentinel.ai_next); 1374 return error; 1375 } 1376 1377 /* 1378 * numeric hostname with scope 1379 */ 1380 static int 1381 explore_numeric_scope(const struct addrinfo *pai, const char *hostname, 1382 const char *servname, struct addrinfo **res, struct servent_data *svd) 1383 { 1384 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 1385 return explore_numeric(pai, hostname, servname, res, hostname, svd); 1386 #else 1387 const struct afd *afd; 1388 struct addrinfo *cur; 1389 int error; 1390 char *cp, *hostname2 = NULL, *scope, *addr; 1391 struct sockaddr_in6 *sin6; 1392 1393 _DIAGASSERT(pai != NULL); 1394 /* hostname may be NULL */ 1395 /* servname may be NULL */ 1396 _DIAGASSERT(res != NULL); 1397 1398 /* 1399 * if the servname does not match socktype/protocol, ignore it. 1400 */ 1401 if (get_portmatch(pai, servname, svd) != 0) 1402 return 0; 1403 1404 afd = find_afd(pai->ai_family); 1405 if (afd == NULL) 1406 return 0; 1407 1408 if (!afd->a_scoped) 1409 return explore_numeric(pai, hostname, servname, res, hostname, 1410 svd); 1411 1412 cp = strchr(hostname, SCOPE_DELIMITER); 1413 if (cp == NULL) 1414 return explore_numeric(pai, hostname, servname, res, hostname, 1415 svd); 1416 1417 /* 1418 * Handle special case of <scoped_address><delimiter><scope id> 1419 */ 1420 hostname2 = strdup(hostname); 1421 if (hostname2 == NULL) 1422 return EAI_MEMORY; 1423 /* terminate at the delimiter */ 1424 hostname2[cp - hostname] = '\0'; 1425 addr = hostname2; 1426 scope = cp + 1; 1427 1428 error = explore_numeric(pai, addr, servname, res, hostname, svd); 1429 if (error == 0) { 1430 u_int32_t scopeid; 1431 1432 for (cur = *res; cur; cur = cur->ai_next) { 1433 if (cur->ai_family != AF_INET6) 1434 continue; 1435 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1436 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1437 free(hostname2); 1438 return EAI_NODATA; /* XXX: is return OK? */ 1439 } 1440 sin6->sin6_scope_id = scopeid; 1441 } 1442 } 1443 1444 free(hostname2); 1445 1446 return error; 1447 #endif 1448 } 1449 1450 static int 1451 get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) 1452 { 1453 1454 _DIAGASSERT(pai != NULL); 1455 _DIAGASSERT(ai != NULL); 1456 _DIAGASSERT(str != NULL); 1457 1458 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1459 ai->ai_canonname = strdup(str); 1460 if (ai->ai_canonname == NULL) 1461 return EAI_MEMORY; 1462 } 1463 return 0; 1464 } 1465 1466 struct addrinfo * 1467 allocaddrinfo(socklen_t addrlen) 1468 { 1469 struct addrinfo *ai; 1470 1471 ai = calloc(sizeof(struct addrinfo) + addrlen, 1); 1472 if (ai) { 1473 ai->ai_addr = (void *)(ai+1); 1474 ai->ai_addrlen = ai->ai_addr->sa_len = addrlen; 1475 } 1476 1477 return ai; 1478 } 1479 1480 static struct addrinfo * 1481 get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) 1482 { 1483 char *p; 1484 struct addrinfo *ai; 1485 struct sockaddr *save; 1486 1487 _DIAGASSERT(pai != NULL); 1488 _DIAGASSERT(afd != NULL); 1489 _DIAGASSERT(addr != NULL); 1490 1491 ai = allocaddrinfo((socklen_t)afd->a_socklen); 1492 if (ai == NULL) 1493 return NULL; 1494 1495 save = ai->ai_addr; 1496 memcpy(ai, pai, sizeof(struct addrinfo)); 1497 1498 /* since we just overwrote all of ai, we have 1499 to restore ai_addr and ai_addrlen */ 1500 ai->ai_addr = save; 1501 ai->ai_addrlen = (socklen_t)afd->a_socklen; 1502 1503 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1504 p = (char *)(void *)(ai->ai_addr); 1505 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1506 return ai; 1507 } 1508 1509 static int 1510 get_portmatch(const struct addrinfo *ai, const char *servname, 1511 struct servent_data *svd) 1512 { 1513 1514 _DIAGASSERT(ai != NULL); 1515 /* servname may be NULL */ 1516 1517 return get_port(ai, servname, 1, svd); 1518 } 1519 1520 static int 1521 get_port(const struct addrinfo *ai, const char *servname, int matchonly, 1522 struct servent_data *svd) 1523 { 1524 const char *proto; 1525 struct servent *sp; 1526 int port; 1527 int allownumeric; 1528 1529 _DIAGASSERT(ai != NULL); 1530 /* servname may be NULL */ 1531 1532 if (servname == NULL) 1533 return 0; 1534 switch (ai->ai_family) { 1535 case AF_INET: 1536 #ifdef AF_INET6 1537 case AF_INET6: 1538 #endif 1539 break; 1540 default: 1541 return 0; 1542 } 1543 1544 switch (ai->ai_socktype) { 1545 case SOCK_RAW: 1546 return EAI_SERVICE; 1547 case SOCK_DGRAM: 1548 case SOCK_STREAM: 1549 allownumeric = 1; 1550 break; 1551 case ANY: 1552 /* 1553 * This was 0. It is now 1 so that queries specifying 1554 * a NULL hint, or hint without socktype (but, hopefully, 1555 * with protocol) and numeric address actually work. 1556 */ 1557 allownumeric = 1; 1558 break; 1559 default: 1560 return EAI_SOCKTYPE; 1561 } 1562 1563 port = str2number(servname); 1564 if (port >= 0) { 1565 if (!allownumeric) 1566 return EAI_SERVICE; 1567 if (port < 0 || port > 65535) 1568 return EAI_SERVICE; 1569 port = htons(port); 1570 } else { 1571 struct servent sv; 1572 if (ai->ai_flags & AI_NUMERICSERV) 1573 return EAI_NONAME; 1574 1575 switch (ai->ai_socktype) { 1576 case SOCK_DGRAM: 1577 proto = "udp"; 1578 break; 1579 case SOCK_STREAM: 1580 proto = "tcp"; 1581 break; 1582 default: 1583 proto = NULL; 1584 break; 1585 } 1586 1587 sp = getservbyname_r(servname, proto, &sv, svd); 1588 if (sp == NULL) 1589 return EAI_SERVICE; 1590 port = sp->s_port; 1591 } 1592 1593 if (!matchonly) 1594 *getport(__UNCONST(ai)) = port; 1595 return 0; 1596 } 1597 1598 static const struct afd * 1599 find_afd(int af) 1600 { 1601 const struct afd *afd; 1602 1603 if (af == PF_UNSPEC) 1604 return NULL; 1605 for (afd = afdl; afd->a_af; afd++) { 1606 if (afd->a_af == af) 1607 return afd; 1608 } 1609 return NULL; 1610 } 1611 1612 /* 1613 * AI_ADDRCONFIG check: Build a mask containing a bit set for each address 1614 * family configured in the system. 1615 * 1616 */ 1617 static int 1618 addrconfig(uint64_t *mask) 1619 { 1620 struct ifaddrs *ifaddrs, *ifa; 1621 1622 if (getifaddrs(&ifaddrs) == -1) 1623 return -1; 1624 1625 *mask = 0; 1626 for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) 1627 if (ifa->ifa_addr && (ifa->ifa_flags & IFF_UP)) { 1628 _DIAGASSERT(ifa->ifa_addr->sa_family < 64); 1629 *mask |= (uint64_t)1 << ifa->ifa_addr->sa_family; 1630 } 1631 1632 freeifaddrs(ifaddrs); 1633 return 0; 1634 } 1635 1636 #ifdef INET6 1637 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1638 static int 1639 ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid) 1640 { 1641 u_long lscopeid; 1642 struct in6_addr *a6; 1643 char *ep; 1644 1645 _DIAGASSERT(scope != NULL); 1646 _DIAGASSERT(sin6 != NULL); 1647 _DIAGASSERT(scopeid != NULL); 1648 1649 a6 = &sin6->sin6_addr; 1650 1651 /* empty scopeid portion is invalid */ 1652 if (*scope == '\0') 1653 return -1; 1654 1655 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1656 /* 1657 * We currently assume a one-to-one mapping between links 1658 * and interfaces, so we simply use interface indices for 1659 * like-local scopes. 1660 */ 1661 *scopeid = if_nametoindex(scope); 1662 if (*scopeid == 0) 1663 goto trynumeric; 1664 return 0; 1665 } 1666 1667 /* still unclear about literal, allow numeric only - placeholder */ 1668 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1669 goto trynumeric; 1670 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1671 goto trynumeric; 1672 else 1673 goto trynumeric; /* global */ 1674 1675 /* try to convert to a numeric id as a last resort */ 1676 trynumeric: 1677 errno = 0; 1678 lscopeid = strtoul(scope, &ep, 10); 1679 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1680 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1681 return 0; 1682 else 1683 return -1; 1684 } 1685 #endif 1686 1687 /* code duplicate with gethnamaddr.c */ 1688 1689 static const char AskedForGot[] = 1690 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1691 1692 #define maybe_ok(res, nm, ok) (((res)->options & RES_NOCHECKNAME) != 0U || \ 1693 (ok)(nm) != 0) 1694 static struct addrinfo * 1695 getanswer(res_state res, const querybuf *answer, int anslen, const char *qname, 1696 int qtype, const struct addrinfo *pai) 1697 { 1698 struct addrinfo sentinel, *cur; 1699 struct addrinfo ai, *aip; 1700 const struct afd *afd; 1701 char *canonname; 1702 const HEADER *hp; 1703 const u_char *cp; 1704 int n; 1705 const u_char *eom; 1706 char *bp, *ep; 1707 int type, class, ancount, qdcount; 1708 int haveanswer, had_error; 1709 char tbuf[MAXDNAME]; 1710 int (*name_ok) (const char *); 1711 char hostbuf[8*1024]; 1712 int port, pri, weight; 1713 struct srvinfo *srvlist, *srv, *csrv; 1714 1715 _DIAGASSERT(answer != NULL); 1716 _DIAGASSERT(qname != NULL); 1717 _DIAGASSERT(pai != NULL); 1718 _DIAGASSERT(res != NULL); 1719 1720 memset(&sentinel, 0, sizeof(sentinel)); 1721 cur = &sentinel; 1722 1723 canonname = NULL; 1724 eom = answer->buf + anslen; 1725 switch (qtype) { 1726 case T_A: 1727 case T_AAAA: 1728 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1729 name_ok = res_hnok; 1730 break; 1731 case T_SRV: 1732 name_ok = gai_srvok; 1733 break; 1734 default: 1735 return NULL; /* XXX should be abort(); */ 1736 } 1737 /* 1738 * find first satisfactory answer 1739 */ 1740 hp = &answer->hdr; 1741 ancount = ntohs(hp->ancount); 1742 qdcount = ntohs(hp->qdcount); 1743 bp = hostbuf; 1744 ep = hostbuf + sizeof hostbuf; 1745 cp = answer->buf + HFIXEDSZ; 1746 if (qdcount != 1) { 1747 h_errno = NO_RECOVERY; 1748 return NULL; 1749 } 1750 n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp)); 1751 if ((n < 0) || !maybe_ok(res, bp, name_ok)) { 1752 h_errno = NO_RECOVERY; 1753 return NULL; 1754 } 1755 cp += n + QFIXEDSZ; 1756 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1757 /* res_send() has already verified that the query name is the 1758 * same as the one we sent; this just gets the expanded name 1759 * (i.e., with the succeeding search-domain tacked on). 1760 */ 1761 n = (int)strlen(bp) + 1; /* for the \0 */ 1762 if (n >= MAXHOSTNAMELEN) { 1763 h_errno = NO_RECOVERY; 1764 return NULL; 1765 } 1766 canonname = bp; 1767 bp += n; 1768 /* The qname can be abbreviated, but h_name is now absolute. */ 1769 qname = canonname; 1770 } 1771 haveanswer = 0; 1772 had_error = 0; 1773 srvlist = NULL; 1774 while (ancount-- > 0 && cp < eom && !had_error) { 1775 n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp)); 1776 if ((n < 0) || !maybe_ok(res, bp, name_ok)) { 1777 had_error++; 1778 continue; 1779 } 1780 cp += n; /* name */ 1781 type = _getshort(cp); 1782 cp += INT16SZ; /* type */ 1783 class = _getshort(cp); 1784 cp += INT16SZ + INT32SZ; /* class, TTL */ 1785 n = _getshort(cp); 1786 cp += INT16SZ; /* len */ 1787 if (class != C_IN) { 1788 /* XXX - debug? syslog? */ 1789 cp += n; 1790 continue; /* XXX - had_error++ ? */ 1791 } 1792 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1793 type == T_CNAME) { 1794 n = dn_expand(answer->buf, eom, cp, tbuf, (int)sizeof tbuf); 1795 if ((n < 0) || !maybe_ok(res, tbuf, name_ok)) { 1796 had_error++; 1797 continue; 1798 } 1799 cp += n; 1800 /* Get canonical name. */ 1801 n = (int)strlen(tbuf) + 1; /* for the \0 */ 1802 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1803 had_error++; 1804 continue; 1805 } 1806 strlcpy(bp, tbuf, (size_t)(ep - bp)); 1807 canonname = bp; 1808 bp += n; 1809 continue; 1810 } 1811 if (qtype == T_ANY) { 1812 if (!(type == T_A || type == T_AAAA)) { 1813 cp += n; 1814 continue; 1815 } 1816 } else if (type != qtype) { 1817 if (type != T_KEY && type != T_SIG) { 1818 struct syslog_data sd = SYSLOG_DATA_INIT; 1819 syslog_r(LOG_NOTICE|LOG_AUTH, &sd, 1820 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1821 qname, p_class(C_IN), p_type(qtype), 1822 p_type(type)); 1823 } 1824 cp += n; 1825 continue; /* XXX - had_error++ ? */ 1826 } 1827 switch (type) { 1828 case T_A: 1829 case T_AAAA: 1830 if (strcasecmp(canonname, bp) != 0) { 1831 struct syslog_data sd = SYSLOG_DATA_INIT; 1832 syslog_r(LOG_NOTICE|LOG_AUTH, &sd, 1833 AskedForGot, canonname, bp); 1834 cp += n; 1835 continue; /* XXX - had_error++ ? */ 1836 } 1837 if (type == T_A && n != INADDRSZ) { 1838 cp += n; 1839 continue; 1840 } 1841 if (type == T_AAAA && n != IN6ADDRSZ) { 1842 cp += n; 1843 continue; 1844 } 1845 if (type == T_AAAA) { 1846 struct in6_addr in6; 1847 memcpy(&in6, cp, IN6ADDRSZ); 1848 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1849 cp += n; 1850 continue; 1851 } 1852 } 1853 if (!haveanswer) { 1854 int nn; 1855 1856 canonname = bp; 1857 nn = (int)strlen(bp) + 1; /* for the \0 */ 1858 bp += nn; 1859 } 1860 1861 /* don't overwrite pai */ 1862 ai = *pai; 1863 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1864 afd = find_afd(ai.ai_family); 1865 if (afd == NULL) { 1866 cp += n; 1867 continue; 1868 } 1869 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1870 if (cur->ai_next == NULL) 1871 had_error++; 1872 while (cur && cur->ai_next) 1873 cur = cur->ai_next; 1874 cp += n; 1875 break; 1876 case T_SRV: 1877 /* Add to SRV list. Insertion sort on priority. */ 1878 pri = _getshort(cp); 1879 cp += INT16SZ; 1880 weight = _getshort(cp); 1881 cp += INT16SZ; 1882 port = _getshort(cp); 1883 cp += INT16SZ; 1884 n = dn_expand(answer->buf, eom, cp, tbuf, 1885 (int)sizeof(tbuf)); 1886 if ((n < 0) || !maybe_ok(res, tbuf, res_hnok)) { 1887 had_error++; 1888 continue; 1889 } 1890 cp += n; 1891 if (strlen(tbuf) + 1 >= MAXDNAME) { 1892 had_error++; 1893 continue; 1894 } 1895 srv = malloc(sizeof(*srv)); 1896 if (!srv) { 1897 had_error++; 1898 continue; 1899 } 1900 strlcpy(srv->name, tbuf, sizeof(srv->name)); 1901 srv->pri = pri; 1902 srv->weight = weight; 1903 srv->port = port; 1904 /* Weight 0 is sorted before other weights. */ 1905 if (!srvlist 1906 || srv->pri < srvlist->pri 1907 || (srv->pri == srvlist->pri && 1908 (!srv->weight || srvlist->weight))) { 1909 srv->next = srvlist; 1910 srvlist = srv; 1911 } else { 1912 for (csrv = srvlist; 1913 csrv->next && csrv->next->pri <= srv->pri; 1914 csrv = csrv->next) { 1915 if (csrv->next->pri == srv->pri 1916 && (!srv->weight || 1917 csrv->next->weight)) 1918 break; 1919 } 1920 srv->next = csrv->next; 1921 csrv->next = srv; 1922 } 1923 continue; /* Don't add to haveanswer yet. */ 1924 default: 1925 abort(); 1926 } 1927 if (!had_error) 1928 haveanswer++; 1929 } 1930 1931 if (srvlist) { 1932 /* 1933 * Check for explicit rejection. 1934 */ 1935 if (!srvlist->next && !srvlist->name[0]) { 1936 free(srvlist); 1937 h_errno = HOST_NOT_FOUND; 1938 return NULL; 1939 } 1940 1941 while (srvlist) { 1942 struct res_target q, q2; 1943 1944 srv = srvlist; 1945 srvlist = srvlist->next; 1946 1947 /* 1948 * Since res_* doesn't give the additional 1949 * section, we always look up. 1950 */ 1951 memset(&q, 0, sizeof(q)); 1952 memset(&q2, 0, sizeof(q2)); 1953 1954 q.name = srv->name; 1955 q.qclass = C_IN; 1956 q.qtype = T_AAAA; 1957 q.next = &q2; 1958 q2.name = srv->name; 1959 q2.qclass = C_IN; 1960 q2.qtype = T_A; 1961 1962 aip = _dns_query(&q, pai, res, 0); 1963 1964 if (aip != NULL) { 1965 cur->ai_next = aip; 1966 while (cur && cur->ai_next) { 1967 cur = cur->ai_next; 1968 *getport(cur) = htons(srv->port); 1969 haveanswer++; 1970 } 1971 } 1972 free(srv); 1973 } 1974 } 1975 if (haveanswer) { 1976 if (!sentinel.ai_next->ai_canonname) 1977 (void)get_canonname(pai, sentinel.ai_next, 1978 canonname ? canonname : qname); 1979 h_errno = NETDB_SUCCESS; 1980 return sentinel.ai_next; 1981 } 1982 1983 /* We could have walked a CNAME chain, */ 1984 /* but the ultimate target may not have what we looked for */ 1985 h_errno = ntohs(hp->ancount) > 0? NO_DATA : NO_RECOVERY; 1986 return NULL; 1987 } 1988 1989 #define SORTEDADDR(p) (((struct sockaddr_in *)(void *)(p->ai_next->ai_addr))->sin_addr.s_addr) 1990 #define SORTMATCH(p, s) ((SORTEDADDR(p) & (s).mask) == (s).addr.s_addr) 1991 1992 static void 1993 aisort(struct addrinfo *s, res_state res) 1994 { 1995 struct addrinfo head, *t, *p; 1996 int i; 1997 1998 head.ai_next = NULL; 1999 t = &head; 2000 2001 for (i = 0; i < res->nsort; i++) { 2002 p = s; 2003 while (p->ai_next) { 2004 if ((p->ai_next->ai_family != AF_INET) 2005 || SORTMATCH(p, res->sort_list[i])) { 2006 t->ai_next = p->ai_next; 2007 t = t->ai_next; 2008 p->ai_next = p->ai_next->ai_next; 2009 } else { 2010 p = p->ai_next; 2011 } 2012 } 2013 } 2014 2015 /* add rest of list and reset s to the new list*/ 2016 t->ai_next = s->ai_next; 2017 s->ai_next = head.ai_next; 2018 } 2019 2020 static struct addrinfo * 2021 _dns_query(struct res_target *q, const struct addrinfo *pai, 2022 res_state res, int dosearch) 2023 { 2024 struct res_target *q2 = q->next; 2025 querybuf *buf, *buf2; 2026 struct addrinfo sentinel, *cur, *ai; 2027 2028 #ifdef DNS_DEBUG 2029 struct res_target *iter; 2030 for (iter = q; iter; iter = iter->next) 2031 printf("Query type %d for %s\n", iter->qtype, iter->name); 2032 #endif 2033 2034 buf = malloc(sizeof(*buf)); 2035 if (buf == NULL) { 2036 h_errno = NETDB_INTERNAL; 2037 return NULL; 2038 } 2039 buf2 = malloc(sizeof(*buf2)); 2040 if (buf2 == NULL) { 2041 free(buf); 2042 h_errno = NETDB_INTERNAL; 2043 return NULL; 2044 } 2045 2046 memset(&sentinel, 0, sizeof(sentinel)); 2047 cur = &sentinel; 2048 2049 q->answer = buf->buf; 2050 q->anslen = sizeof(buf->buf); 2051 if (q2) { 2052 q2->answer = buf2->buf; 2053 q2->anslen = sizeof(buf2->buf); 2054 } 2055 2056 if (dosearch) { 2057 if (res_searchN(q->name, q, res) < 0) 2058 goto out; 2059 } else { 2060 if (res_queryN(q->name, q, res) < 0) 2061 goto out; 2062 } 2063 2064 ai = getanswer(res, buf, q->n, q->name, q->qtype, pai); 2065 if (ai) { 2066 cur->ai_next = ai; 2067 while (cur && cur->ai_next) 2068 cur = cur->ai_next; 2069 } 2070 if (q2) { 2071 ai = getanswer(res, buf2, q2->n, q2->name, q2->qtype, pai); 2072 if (ai) 2073 cur->ai_next = ai; 2074 } 2075 free(buf); 2076 free(buf2); 2077 return sentinel.ai_next; 2078 out: 2079 free(buf); 2080 free(buf2); 2081 return NULL; 2082 } 2083 2084 /*ARGSUSED*/ 2085 static struct addrinfo * 2086 _dns_srv_lookup(const char *name, const char *servname, 2087 const struct addrinfo *pai) 2088 { 2089 static const char * const srvprotos[] = { "tcp", "udp" }; 2090 static const int srvnottype[] = { SOCK_DGRAM, SOCK_STREAM }; 2091 static const int nsrvprotos = 2; 2092 struct addrinfo sentinel, *cur, *ai; 2093 struct servent *serv, sv; 2094 struct servent_data svd; 2095 struct res_target q; 2096 res_state res; 2097 char *tname; 2098 int i; 2099 2100 res = __res_get_state(); 2101 if (res == NULL) 2102 return NULL; 2103 2104 memset(&svd, 0, sizeof(svd)); 2105 memset(&sentinel, 0, sizeof(sentinel)); 2106 cur = &sentinel; 2107 2108 /* 2109 * Iterate over supported SRV protocols. 2110 * (currently UDP and TCP only) 2111 */ 2112 for (i = 0; i < nsrvprotos; i++) { 2113 /* 2114 * Check that the caller didn't specify a hint 2115 * which precludes this protocol. 2116 */ 2117 if (pai->ai_socktype == srvnottype[i]) 2118 continue; 2119 /* 2120 * If the caller specified a port, 2121 * then lookup the database for the 2122 * official service name. 2123 */ 2124 serv = getservbyname_r(servname, srvprotos[i], &sv, &svd); 2125 if (serv == NULL) 2126 continue; 2127 2128 /* 2129 * Construct service DNS name. 2130 */ 2131 if (asprintf(&tname, "_%s._%s.%s", serv->s_name, serv->s_proto, 2132 name) < 0) 2133 continue; 2134 2135 memset(&q, 0, sizeof(q)); 2136 q.name = tname; 2137 q.qclass = C_IN; 2138 q.qtype = T_SRV; 2139 2140 /* 2141 * Do SRV query. 2142 */ 2143 ai = _dns_query(&q, pai, res, 1); 2144 if (ai) { 2145 cur->ai_next = ai; 2146 while (cur && cur->ai_next) 2147 cur = cur->ai_next; 2148 } 2149 free(tname); 2150 } 2151 2152 if (res->nsort) 2153 aisort(&sentinel, res); 2154 2155 __res_put_state(res); 2156 2157 return sentinel.ai_next; 2158 } 2159 2160 /*ARGSUSED*/ 2161 static struct addrinfo * 2162 _dns_host_lookup(const char *name, const struct addrinfo *pai) 2163 { 2164 struct res_target q, q2; 2165 struct addrinfo sentinel, *ai; 2166 res_state res; 2167 2168 res = __res_get_state(); 2169 if (res == NULL) 2170 return NULL; 2171 2172 memset(&q, 0, sizeof(q2)); 2173 memset(&q2, 0, sizeof(q2)); 2174 2175 switch (pai->ai_family) { 2176 case AF_UNSPEC: 2177 /* prefer IPv6 */ 2178 q.name = name; 2179 q.qclass = C_IN; 2180 q.qtype = T_AAAA; 2181 q.next = &q2; 2182 q2.name = name; 2183 q2.qclass = C_IN; 2184 q2.qtype = T_A; 2185 break; 2186 case AF_INET: 2187 q.name = name; 2188 q.qclass = C_IN; 2189 q.qtype = T_A; 2190 break; 2191 case AF_INET6: 2192 q.name = name; 2193 q.qclass = C_IN; 2194 q.qtype = T_AAAA; 2195 break; 2196 default: 2197 __res_put_state(res); 2198 h_errno = NETDB_INTERNAL; 2199 return NULL; 2200 } 2201 2202 ai = _dns_query(&q, pai, res, 1); 2203 2204 memset(&sentinel, 0, sizeof(sentinel)); 2205 sentinel.ai_next = ai; 2206 2207 if (ai != NULL && res->nsort) 2208 aisort(&sentinel, res); 2209 2210 __res_put_state(res); 2211 2212 return sentinel.ai_next; 2213 } 2214 2215 /*ARGSUSED*/ 2216 static int 2217 _dns_getaddrinfo(void *rv, void *cb_data, va_list ap) 2218 { 2219 struct addrinfo *ai = NULL; 2220 const char *name, *servname; 2221 const struct addrinfo *pai; 2222 2223 name = va_arg(ap, char *); 2224 pai = va_arg(ap, const struct addrinfo *); 2225 servname = va_arg(ap, char *); 2226 2227 /* 2228 * Try doing SRV lookup on service first. 2229 */ 2230 if (servname 2231 #ifdef AI_SRV 2232 && (pai->ai_flags & AI_SRV) 2233 #endif 2234 && !(pai->ai_flags & AI_NUMERICSERV) 2235 && str2number(servname) == -1) { 2236 2237 #ifdef DNS_DEBUG 2238 printf("%s: try SRV lookup\n", __func__); 2239 #endif 2240 ai = _dns_srv_lookup(name, servname, pai); 2241 } 2242 2243 /* 2244 * Do lookup on name. 2245 */ 2246 if (ai == NULL) { 2247 2248 #ifdef DNS_DEBUG 2249 printf("%s: try HOST lookup\n", __func__); 2250 #endif 2251 ai = _dns_host_lookup(name, pai); 2252 2253 if (ai == NULL) { 2254 switch (h_errno) { 2255 case HOST_NOT_FOUND: 2256 case NO_DATA: // XXX: Perhaps we could differentiate 2257 // So that we could return EAI_NODATA? 2258 return NS_NOTFOUND; 2259 case TRY_AGAIN: 2260 return NS_TRYAGAIN; 2261 default: 2262 return NS_UNAVAIL; 2263 } 2264 } 2265 } 2266 2267 *((struct addrinfo **)rv) = ai; 2268 return NS_SUCCESS; 2269 } 2270 2271 static void 2272 _sethtent(FILE **hostf) 2273 { 2274 2275 if (!*hostf) 2276 *hostf = fopen(_PATH_HOSTS, "re"); 2277 else 2278 rewind(*hostf); 2279 } 2280 2281 static void 2282 _endhtent(FILE **hostf) 2283 { 2284 2285 if (*hostf) { 2286 (void) fclose(*hostf); 2287 *hostf = NULL; 2288 } 2289 } 2290 2291 static struct addrinfo * 2292 _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) 2293 { 2294 char *p; 2295 char *cp, *tname, *cname; 2296 struct addrinfo hints, *res0, *res; 2297 int error; 2298 const char *addr; 2299 char hostbuf[8*1024]; 2300 2301 _DIAGASSERT(name != NULL); 2302 _DIAGASSERT(pai != NULL); 2303 2304 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "re"))) 2305 return NULL; 2306 again: 2307 if (!(p = fgets(hostbuf, (int)sizeof hostbuf, *hostf))) 2308 return NULL; 2309 if (*p == '#') 2310 goto again; 2311 if (!(cp = strpbrk(p, "#\n"))) 2312 goto again; 2313 *cp = '\0'; 2314 if (!(cp = strpbrk(p, " \t"))) 2315 goto again; 2316 *cp++ = '\0'; 2317 addr = p; 2318 /* if this is not something we're looking for, skip it. */ 2319 cname = NULL; 2320 while (cp && *cp) { 2321 if (*cp == ' ' || *cp == '\t') { 2322 cp++; 2323 continue; 2324 } 2325 if (!cname) 2326 cname = cp; 2327 tname = cp; 2328 if ((cp = strpbrk(cp, " \t")) != NULL) 2329 *cp++ = '\0'; 2330 if (strcasecmp(name, tname) == 0) 2331 goto found; 2332 } 2333 goto again; 2334 2335 found: 2336 hints = *pai; 2337 hints.ai_flags = AI_NUMERICHOST; 2338 error = getaddrinfo(addr, NULL, &hints, &res0); 2339 if (error) 2340 goto again; 2341 for (res = res0; res; res = res->ai_next) { 2342 /* cover it up */ 2343 res->ai_flags = pai->ai_flags; 2344 2345 if (pai->ai_flags & AI_CANONNAME) { 2346 if (get_canonname(pai, res, cname) != 0) { 2347 freeaddrinfo(res0); 2348 goto again; 2349 } 2350 } 2351 } 2352 return res0; 2353 } 2354 2355 /*ARGSUSED*/ 2356 static int 2357 _files_getaddrinfo(void *rv, void *cb_data, va_list ap) 2358 { 2359 const char *name; 2360 const struct addrinfo *pai; 2361 struct addrinfo sentinel, *cur; 2362 struct addrinfo *p; 2363 #ifndef _REENTRANT 2364 static 2365 #endif 2366 FILE *hostf = NULL; 2367 2368 name = va_arg(ap, char *); 2369 pai = va_arg(ap, const struct addrinfo *); 2370 2371 memset(&sentinel, 0, sizeof(sentinel)); 2372 cur = &sentinel; 2373 2374 _sethtent(&hostf); 2375 while ((p = _gethtent(&hostf, name, pai)) != NULL) { 2376 cur->ai_next = p; 2377 while (cur && cur->ai_next) 2378 cur = cur->ai_next; 2379 } 2380 _endhtent(&hostf); 2381 2382 *((struct addrinfo **)rv) = sentinel.ai_next; 2383 if (sentinel.ai_next == NULL) 2384 return NS_NOTFOUND; 2385 return NS_SUCCESS; 2386 } 2387 2388 #ifdef YP 2389 /*ARGSUSED*/ 2390 static struct addrinfo * 2391 _yphostent(char *line, const struct addrinfo *pai) 2392 { 2393 struct addrinfo sentinel, *cur; 2394 struct addrinfo hints, *res, *res0; 2395 int error; 2396 char *p; 2397 const char *addr, *canonname; 2398 char *nextline; 2399 char *cp; 2400 2401 _DIAGASSERT(line != NULL); 2402 _DIAGASSERT(pai != NULL); 2403 2404 p = line; 2405 addr = canonname = NULL; 2406 2407 memset(&sentinel, 0, sizeof(sentinel)); 2408 cur = &sentinel; 2409 2410 nextline: 2411 /* terminate line */ 2412 cp = strchr(p, '\n'); 2413 if (cp) { 2414 *cp++ = '\0'; 2415 nextline = cp; 2416 } else 2417 nextline = NULL; 2418 2419 cp = strpbrk(p, " \t"); 2420 if (cp == NULL) { 2421 if (canonname == NULL) 2422 return NULL; 2423 else 2424 goto done; 2425 } 2426 *cp++ = '\0'; 2427 2428 addr = p; 2429 2430 while (cp && *cp) { 2431 if (*cp == ' ' || *cp == '\t') { 2432 cp++; 2433 continue; 2434 } 2435 if (!canonname) 2436 canonname = cp; 2437 if ((cp = strpbrk(cp, " \t")) != NULL) 2438 *cp++ = '\0'; 2439 } 2440 2441 hints = *pai; 2442 hints.ai_flags = AI_NUMERICHOST; 2443 error = getaddrinfo(addr, NULL, &hints, &res0); 2444 if (error == 0) { 2445 for (res = res0; res; res = res->ai_next) { 2446 /* cover it up */ 2447 res->ai_flags = pai->ai_flags; 2448 2449 if (pai->ai_flags & AI_CANONNAME) 2450 (void)get_canonname(pai, res, canonname); 2451 } 2452 } else 2453 res0 = NULL; 2454 if (res0) { 2455 cur->ai_next = res0; 2456 while (cur->ai_next) 2457 cur = cur->ai_next; 2458 } 2459 2460 if (nextline) { 2461 p = nextline; 2462 goto nextline; 2463 } 2464 2465 done: 2466 return sentinel.ai_next; 2467 } 2468 2469 /*ARGSUSED*/ 2470 static int 2471 _yp_getaddrinfo(void *rv, void *cb_data, va_list ap) 2472 { 2473 struct addrinfo sentinel, *cur; 2474 struct addrinfo *ai = NULL; 2475 char *ypbuf; 2476 int ypbuflen, r; 2477 const char *name; 2478 const struct addrinfo *pai; 2479 char *ypdomain; 2480 2481 if (_yp_check(&ypdomain) == 0) 2482 return NS_UNAVAIL; 2483 2484 name = va_arg(ap, char *); 2485 pai = va_arg(ap, const struct addrinfo *); 2486 2487 memset(&sentinel, 0, sizeof(sentinel)); 2488 cur = &sentinel; 2489 2490 /* hosts.byname is only for IPv4 (Solaris8) */ 2491 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2492 r = yp_match(ypdomain, "hosts.byname", name, 2493 (int)strlen(name), &ypbuf, &ypbuflen); 2494 if (r == 0) { 2495 struct addrinfo ai4; 2496 2497 ai4 = *pai; 2498 ai4.ai_family = AF_INET; 2499 ai = _yphostent(ypbuf, &ai4); 2500 if (ai) { 2501 cur->ai_next = ai; 2502 while (cur && cur->ai_next) 2503 cur = cur->ai_next; 2504 } 2505 } 2506 free(ypbuf); 2507 } 2508 2509 /* ipnodes.byname can hold both IPv4/v6 */ 2510 r = yp_match(ypdomain, "ipnodes.byname", name, 2511 (int)strlen(name), &ypbuf, &ypbuflen); 2512 if (r == 0) { 2513 ai = _yphostent(ypbuf, pai); 2514 if (ai) 2515 cur->ai_next = ai; 2516 free(ypbuf); 2517 } 2518 2519 if (sentinel.ai_next == NULL) { 2520 h_errno = HOST_NOT_FOUND; 2521 return NS_NOTFOUND; 2522 } 2523 *((struct addrinfo **)rv) = sentinel.ai_next; 2524 return NS_SUCCESS; 2525 } 2526 #endif 2527 2528 /* resolver logic */ 2529 2530 /* 2531 * Formulate a normal query, send, and await answer. 2532 * Returned answer is placed in supplied buffer "answer". 2533 * Perform preliminary check of answer, returning success only 2534 * if no error is indicated and the answer count is nonzero. 2535 * Return the size of the response on success, -1 on error. 2536 * Error number is left in h_errno. 2537 * 2538 * Caller must parse answer and determine whether it answers the question. 2539 */ 2540 static int 2541 res_queryN(const char *name, /* domain name */ struct res_target *target, 2542 res_state statp) 2543 { 2544 u_char buf[MAXPACKET]; 2545 HEADER *hp; 2546 int n; 2547 struct res_target *t; 2548 int rcode; 2549 u_char *rdata; 2550 int ancount; 2551 2552 _DIAGASSERT(name != NULL); 2553 /* XXX: target may be NULL??? */ 2554 2555 rcode = NOERROR; 2556 ancount = 0; 2557 2558 for (t = target; t; t = t->next) { 2559 int class, type; 2560 u_char *answer; 2561 int anslen; 2562 u_int oflags; 2563 2564 hp = (HEADER *)(void *)t->answer; 2565 oflags = statp->_flags; 2566 2567 again: 2568 hp->rcode = NOERROR; /* default */ 2569 2570 /* make it easier... */ 2571 class = t->qclass; 2572 type = t->qtype; 2573 answer = t->answer; 2574 anslen = t->anslen; 2575 #ifdef DEBUG 2576 if (statp->options & RES_DEBUG) 2577 printf(";; res_nquery(%s, %d, %d)\n", name, class, type); 2578 #endif 2579 2580 n = res_nmkquery(statp, QUERY, name, class, type, NULL, 0, NULL, 2581 buf, (int)sizeof(buf)); 2582 #ifdef RES_USE_EDNS0 2583 if (n > 0 && (statp->_flags & RES_F_EDNS0ERR) == 0 && 2584 (statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0) { 2585 n = res_nopt(statp, n, buf, (int)sizeof(buf), anslen); 2586 rdata = &buf[n]; 2587 if (n > 0 && (statp->options & RES_NSID) != 0U) { 2588 n = res_nopt_rdata(statp, n, buf, 2589 (int)sizeof(buf), 2590 rdata, NS_OPT_NSID, 0, NULL); 2591 } 2592 } 2593 #endif 2594 if (n <= 0) { 2595 #ifdef DEBUG 2596 if (statp->options & RES_DEBUG) 2597 printf(";; res_nquery: mkquery failed\n"); 2598 #endif 2599 h_errno = NO_RECOVERY; 2600 return n; 2601 } 2602 n = res_nsend(statp, buf, n, answer, anslen); 2603 if (n < 0) { 2604 #ifdef RES_USE_EDNS0 2605 /* if the query choked with EDNS0, retry without EDNS0 */ 2606 if ((statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U && 2607 ((oflags ^ statp->_flags) & RES_F_EDNS0ERR) != 0) { 2608 statp->_flags |= RES_F_EDNS0ERR; 2609 if (statp->options & RES_DEBUG) 2610 printf(";; res_nquery: retry without EDNS0\n"); 2611 goto again; 2612 } 2613 #endif 2614 #if 0 2615 #ifdef DEBUG 2616 if (statp->options & RES_DEBUG) 2617 printf(";; res_query: send error\n"); 2618 #endif 2619 h_errno = TRY_AGAIN; 2620 return n; 2621 #endif 2622 } 2623 2624 if (n < 0 || hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2625 rcode = hp->rcode; /* record most recent error */ 2626 #ifdef DEBUG 2627 if (statp->options & RES_DEBUG) 2628 printf(";; rcode = (%s), counts = an:%d ns:%d ar:%d\n", 2629 p_rcode(hp->rcode), 2630 ntohs(hp->ancount), 2631 ntohs(hp->nscount), 2632 ntohs(hp->arcount)); 2633 #endif 2634 continue; 2635 } 2636 2637 ancount += ntohs(hp->ancount); 2638 2639 t->n = n; 2640 } 2641 2642 if (ancount == 0) { 2643 switch (rcode) { 2644 case NXDOMAIN: 2645 h_errno = HOST_NOT_FOUND; 2646 break; 2647 case SERVFAIL: 2648 h_errno = TRY_AGAIN; 2649 break; 2650 case NOERROR: 2651 h_errno = NO_DATA; 2652 break; 2653 case FORMERR: 2654 case NOTIMP: 2655 case REFUSED: 2656 default: 2657 h_errno = NO_RECOVERY; 2658 break; 2659 } 2660 return -1; 2661 } 2662 return ancount; 2663 } 2664 2665 /* 2666 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2667 * Return the size of the response on success, -1 on error. 2668 * If enabled, implement search rules until answer or unrecoverable failure 2669 * is detected. Error code, if any, is left in h_errno. 2670 */ 2671 static int 2672 res_searchN(const char *name, struct res_target *target, res_state res) 2673 { 2674 const char *cp, * const *domain; 2675 HEADER *hp; 2676 u_int dots; 2677 char buf[MAXHOSTNAMELEN]; 2678 int trailing_dot, ret, saved_herrno; 2679 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 2680 2681 _DIAGASSERT(name != NULL); 2682 _DIAGASSERT(target != NULL); 2683 2684 hp = (HEADER *)(void *)target->answer; /*XXX*/ 2685 2686 errno = 0; 2687 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 2688 dots = 0; 2689 for (cp = name; *cp; cp++) 2690 dots += (*cp == '.'); 2691 trailing_dot = 0; 2692 if (cp > name && *--cp == '.') 2693 trailing_dot++; 2694 2695 /* 2696 * if there aren't any dots, it could be a user-level alias 2697 */ 2698 if (!dots && (cp = res_hostalias(res, name, buf, sizeof(buf))) != NULL) { 2699 ret = res_queryN(cp, target, res); 2700 return ret; 2701 } 2702 2703 /* 2704 * If there are dots in the name already, let's just give it a try 2705 * 'as is'. The threshold can be set with the "ndots" option. 2706 */ 2707 saved_herrno = -1; 2708 if (dots >= res->ndots) { 2709 ret = res_querydomainN(name, NULL, target, res); 2710 if (ret > 0) 2711 return ret; 2712 saved_herrno = h_errno; 2713 tried_as_is++; 2714 } 2715 2716 /* 2717 * We do at least one level of search if 2718 * - there is no dot and RES_DEFNAME is set, or 2719 * - there is at least one dot, there is no trailing dot, 2720 * and RES_DNSRCH is set. 2721 */ 2722 if ((!dots && (res->options & RES_DEFNAMES)) || 2723 (dots && !trailing_dot && (res->options & RES_DNSRCH))) { 2724 int done = 0; 2725 2726 for (domain = (const char * const *)res->dnsrch; 2727 *domain && !done; 2728 domain++) { 2729 2730 ret = res_querydomainN(name, *domain, target, res); 2731 if (ret > 0) 2732 return ret; 2733 2734 /* 2735 * If no server present, give up. 2736 * If name isn't found in this domain, 2737 * keep trying higher domains in the search list 2738 * (if that's enabled). 2739 * On a NO_DATA error, keep trying, otherwise 2740 * a wildcard entry of another type could keep us 2741 * from finding this entry higher in the domain. 2742 * If we get some other error (negative answer or 2743 * server failure), then stop searching up, 2744 * but try the input name below in case it's 2745 * fully-qualified. 2746 */ 2747 if (errno == ECONNREFUSED) { 2748 h_errno = TRY_AGAIN; 2749 return -1; 2750 } 2751 2752 switch (h_errno) { 2753 case NO_DATA: 2754 got_nodata++; 2755 /* FALLTHROUGH */ 2756 case HOST_NOT_FOUND: 2757 /* keep trying */ 2758 break; 2759 case TRY_AGAIN: 2760 if (hp->rcode == SERVFAIL) { 2761 /* try next search element, if any */ 2762 got_servfail++; 2763 break; 2764 } 2765 /* FALLTHROUGH */ 2766 default: 2767 /* anything else implies that we're done */ 2768 done++; 2769 } 2770 /* 2771 * if we got here for some reason other than DNSRCH, 2772 * we only wanted one iteration of the loop, so stop. 2773 */ 2774 if (!(res->options & RES_DNSRCH)) 2775 done++; 2776 } 2777 } 2778 2779 /* 2780 * if we have not already tried the name "as is", do that now. 2781 * note that we do this regardless of how many dots were in the 2782 * name or whether it ends with a dot. 2783 */ 2784 if (!tried_as_is) { 2785 ret = res_querydomainN(name, NULL, target, res); 2786 if (ret > 0) 2787 return ret; 2788 } 2789 2790 /* 2791 * if we got here, we didn't satisfy the search. 2792 * if we did an initial full query, return that query's h_errno 2793 * (note that we wouldn't be here if that query had succeeded). 2794 * else if we ever got a nodata, send that back as the reason. 2795 * else send back meaningless h_errno, that being the one from 2796 * the last DNSRCH we did. 2797 */ 2798 if (saved_herrno != -1) 2799 h_errno = saved_herrno; 2800 else if (got_nodata) 2801 h_errno = NO_DATA; 2802 else if (got_servfail) 2803 h_errno = TRY_AGAIN; 2804 return -1; 2805 } 2806 2807 /* 2808 * Perform a call on res_query on the concatenation of name and domain, 2809 * removing a trailing dot from name if domain is NULL. 2810 */ 2811 static int 2812 res_querydomainN(const char *name, const char *domain, 2813 struct res_target *target, res_state res) 2814 { 2815 char nbuf[MAXDNAME]; 2816 const char *longname = nbuf; 2817 size_t n, d; 2818 2819 _DIAGASSERT(name != NULL); 2820 /* XXX: target may be NULL??? */ 2821 2822 #ifdef DEBUG 2823 if (res->options & RES_DEBUG) 2824 printf(";; res_querydomain(%s, %s)\n", 2825 name, domain?domain:"<Nil>"); 2826 #endif 2827 if (domain == NULL) { 2828 /* 2829 * Check for trailing '.'; 2830 * copy without '.' if present. 2831 */ 2832 n = strlen(name); 2833 if (n + 1 > sizeof(nbuf)) { 2834 h_errno = NO_RECOVERY; 2835 return -1; 2836 } 2837 if (n > 0 && name[--n] == '.') { 2838 strncpy(nbuf, name, n); 2839 nbuf[n] = '\0'; 2840 } else 2841 longname = name; 2842 } else { 2843 n = strlen(name); 2844 d = strlen(domain); 2845 if (n + 1 + d + 1 > sizeof(nbuf)) { 2846 h_errno = NO_RECOVERY; 2847 return -1; 2848 } 2849 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2850 } 2851 return res_queryN(longname, target, res); 2852 } 2853 2854 #ifdef TEST 2855 int 2856 main(int argc, char *argv[]) { 2857 struct addrinfo *ai, *sai; 2858 int i, e; 2859 char buf[1024]; 2860 2861 for (i = 1; i < argc; i++) { 2862 if ((e = getaddrinfo(argv[i], NULL, NULL, &sai)) != 0) 2863 warnx("%s: %s", argv[i], gai_strerror(e)); 2864 for (ai = sai; ai; ai = ai->ai_next) { 2865 sockaddr_snprintf(buf, sizeof(buf), "%a", ai->ai_addr); 2866 printf("flags=0x%x family=%d socktype=%d protocol=%d " 2867 "addrlen=%zu addr=%s canonname=%s next=%p\n", 2868 ai->ai_flags, 2869 ai->ai_family, 2870 ai->ai_socktype, 2871 ai->ai_protocol, 2872 (size_t)ai->ai_addrlen, 2873 buf, 2874 ai->ai_canonname, 2875 ai->ai_next); 2876 } 2877 if (sai) 2878 freeaddrinfo(sai); 2879 } 2880 return 0; 2881 } 2882 #endif 2883