1 /* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * "#ifdef FAITH" part is local hack for supporting IPv4-v6 translator. 34 * 35 * Issues to be discussed: 36 * - Thread safe-ness must be checked. 37 * - Return values. There are nonstandard return values defined and used 38 * in the source code. This is because RFC2553 is silent about which error 39 * code must be returned for which situation. 40 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 41 * invalid. current code - SEGV on freeaddrinfo(NULL) 42 * 43 * Note: 44 * - The code filters out AFs that are not supported by the kernel, 45 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 46 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 47 * in ai_flags? 48 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 49 * (1) what should we do against numeric hostname (2) what should we do 50 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 51 * non-loopback address configured? global address configured? 52 * 53 * OS specific notes for netbsd/openbsd/freebsd4/bsdi4: 54 * - To avoid search order issue, we have a big amount of code duplicate 55 * from gethnamaddr.c and some other places. The issues that there's no 56 * lower layer function to lookup "IPv4 or IPv6" record. Calling 57 * gethostbyname2 from getaddrinfo will end up in wrong search order, as 58 * presented above. 59 * 60 * OS specific notes for freebsd4: 61 * - FreeBSD supported $GAI. The code does not. 62 * - FreeBSD allowed classful IPv4 numeric (127.1), the code does not. 63 */ 64 65 #include <sys/cdefs.h> 66 __FBSDID("$FreeBSD$"); 67 68 #include "namespace.h" 69 #include <sys/types.h> 70 #include <sys/param.h> 71 #include <sys/socket.h> 72 #include <net/if.h> 73 #include <netinet/in.h> 74 #include <sys/queue.h> 75 #ifdef INET6 76 #include <net/if_var.h> 77 #include <sys/sysctl.h> 78 #include <netinet6/in6_var.h> /* XXX */ 79 #endif 80 #include <arpa/inet.h> 81 #include <arpa/nameser.h> 82 #include <rpc/rpc.h> 83 #include <rpcsvc/yp_prot.h> 84 #include <rpcsvc/ypclnt.h> 85 #include <netdb.h> 86 #include <pthread.h> 87 #include <resolv.h> 88 #include <string.h> 89 #include <stdlib.h> 90 #include <stddef.h> 91 #include <ctype.h> 92 #include <unistd.h> 93 #include <stdio.h> 94 #include <errno.h> 95 96 #include "res_config.h" 97 98 #ifdef DEBUG 99 #include <syslog.h> 100 #endif 101 102 #include <stdarg.h> 103 #include <nsswitch.h> 104 #include "un-namespace.h" 105 #include "libc_private.h" 106 107 #if defined(__KAME__) && defined(INET6) 108 # define FAITH 109 #endif 110 111 #define SUCCESS 0 112 #define ANY 0 113 #define YES 1 114 #define NO 0 115 116 static const char in_addrany[] = { 0, 0, 0, 0 }; 117 static const char in_loopback[] = { 127, 0, 0, 1 }; 118 #ifdef INET6 119 static const char in6_addrany[] = { 120 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 121 }; 122 static const char in6_loopback[] = { 123 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 124 }; 125 #endif 126 127 struct policyqueue { 128 TAILQ_ENTRY(policyqueue) pc_entry; 129 #ifdef INET6 130 struct in6_addrpolicy pc_policy; 131 #endif 132 }; 133 TAILQ_HEAD(policyhead, policyqueue); 134 135 static const struct afd { 136 int a_af; 137 int a_addrlen; 138 int a_socklen; 139 int a_off; 140 const char *a_addrany; 141 const char *a_loopback; 142 int a_scoped; 143 } afdl [] = { 144 #ifdef INET6 145 #define N_INET6 0 146 {PF_INET6, sizeof(struct in6_addr), 147 sizeof(struct sockaddr_in6), 148 offsetof(struct sockaddr_in6, sin6_addr), 149 in6_addrany, in6_loopback, 1}, 150 #define N_INET 1 151 #else 152 #define N_INET 0 153 #endif 154 {PF_INET, sizeof(struct in_addr), 155 sizeof(struct sockaddr_in), 156 offsetof(struct sockaddr_in, sin_addr), 157 in_addrany, in_loopback, 0}, 158 {0, 0, 0, 0, NULL, NULL, 0}, 159 }; 160 161 struct explore { 162 int e_af; 163 int e_socktype; 164 int e_protocol; 165 const char *e_protostr; 166 int e_wild; 167 #define WILD_AF(ex) ((ex)->e_wild & 0x01) 168 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 169 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 170 }; 171 172 static const struct explore explore[] = { 173 #if 0 174 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 175 #endif 176 #ifdef INET6 177 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 178 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 179 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 180 #endif 181 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 182 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 183 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 184 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 185 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 186 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, 187 { -1, 0, 0, NULL, 0 }, 188 }; 189 190 #ifdef INET6 191 #define PTON_MAX 16 192 #else 193 #define PTON_MAX 4 194 #endif 195 196 #define AIO_SRCFLAG_DEPRECATED 0x1 197 198 struct ai_order { 199 union { 200 struct sockaddr_storage aiou_ss; 201 struct sockaddr aiou_sa; 202 } aio_src_un; 203 #define aio_srcsa aio_src_un.aiou_sa 204 u_int32_t aio_srcflag; 205 int aio_srcscope; 206 int aio_dstscope; 207 struct policyqueue *aio_srcpolicy; 208 struct policyqueue *aio_dstpolicy; 209 struct addrinfo *aio_ai; 210 int aio_matchlen; 211 }; 212 213 static const ns_src default_dns_files[] = { 214 { NSSRC_FILES, NS_SUCCESS }, 215 { NSSRC_DNS, NS_SUCCESS }, 216 { 0 } 217 }; 218 219 struct res_target { 220 struct res_target *next; 221 const char *name; /* domain name */ 222 int qclass, qtype; /* class and type of query */ 223 u_char *answer; /* buffer to put answer */ 224 int anslen; /* size of answer buffer */ 225 int n; /* result length */ 226 }; 227 228 #define MAXPACKET (64*1024) 229 230 typedef union { 231 HEADER hdr; 232 u_char buf[MAXPACKET]; 233 } querybuf; 234 235 static int str_isnumber(const char *); 236 static int explore_null(const struct addrinfo *, 237 const char *, struct addrinfo **); 238 static int explore_numeric(const struct addrinfo *, const char *, 239 const char *, struct addrinfo **); 240 static int explore_numeric_scope(const struct addrinfo *, const char *, 241 const char *, struct addrinfo **); 242 static int get_canonname(const struct addrinfo *, 243 struct addrinfo *, const char *); 244 static struct addrinfo *get_ai(const struct addrinfo *, 245 const struct afd *, const char *); 246 static int get_portmatch(const struct addrinfo *, const char *); 247 static int get_port(struct addrinfo *, const char *, int); 248 static const struct afd *find_afd(int); 249 static int addrconfig(struct addrinfo *); 250 static int comp_dst(const void *, const void *); 251 #ifdef INET6 252 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 253 #endif 254 static int gai_addr2scopetype(struct sockaddr *); 255 256 static int explore_fqdn(const struct addrinfo *, const char *, 257 const char *, struct addrinfo **); 258 259 static int reorder(struct addrinfo *); 260 static int get_addrselectpolicy(struct policyhead *); 261 static void free_addrselectpolicy(struct policyhead *); 262 static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 263 struct policyhead *); 264 265 static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 266 const struct addrinfo *); 267 #if defined(RESOLVSORT) 268 static int addr4sort(struct addrinfo *); 269 #endif 270 static int _dns_getaddrinfo(void *, void *, va_list); 271 static void _sethtent(void); 272 static void _endhtent(void); 273 static struct addrinfo *_gethtent(const char *, const struct addrinfo *); 274 static int _files_getaddrinfo(void *, void *, va_list); 275 #ifdef YP 276 static struct addrinfo *_yphostent(char *, const struct addrinfo *); 277 static int _yp_getaddrinfo(void *, void *, va_list); 278 #endif 279 280 static int res_queryN(const char *, struct res_target *); 281 static int res_searchN(const char *, struct res_target *); 282 static int res_querydomainN(const char *, const char *, 283 struct res_target *); 284 285 static struct ai_errlist { 286 const char *str; 287 int code; 288 } ai_errlist[] = { 289 { "Success", 0, }, 290 { "Temporary failure in name resolution", EAI_AGAIN, }, 291 { "Invalid value for ai_flags", EAI_BADFLAGS, }, 292 { "Non-recoverable failure in name resolution", EAI_FAIL, }, 293 { "ai_family not supported", EAI_FAMILY, }, 294 { "Memory allocation failure", EAI_MEMORY, }, 295 { "hostname nor servname provided, or not known", EAI_NONAME, }, 296 { "servname not supported for ai_socktype", EAI_SERVICE, }, 297 { "ai_socktype not supported", EAI_SOCKTYPE, }, 298 { "System error returned in errno", EAI_SYSTEM, }, 299 { "Invalid value for hints", EAI_BADHINTS, }, 300 { "Resolved protocol is unknown", EAI_PROTOCOL, }, 301 /* backward compatibility with userland code prior to 2553bis-02 */ 302 { "Address family for hostname not supported", 1, }, 303 { "No address associated with hostname", 7, }, 304 { NULL, -1, }, 305 }; 306 307 /* 308 * XXX: Many dependencies are not thread-safe. So, we share lock between 309 * getaddrinfo() and getipnodeby*(). Still, we cannot use 310 * getaddrinfo() and getipnodeby*() in conjunction with other 311 * functions which call them. 312 */ 313 pthread_mutex_t __getaddrinfo_thread_lock = PTHREAD_MUTEX_INITIALIZER; 314 #define THREAD_LOCK() \ 315 if (__isthreaded) _pthread_mutex_lock(&__getaddrinfo_thread_lock); 316 #define THREAD_UNLOCK() \ 317 if (__isthreaded) _pthread_mutex_unlock(&__getaddrinfo_thread_lock); 318 319 /* XXX macros that make external reference is BAD. */ 320 321 #define GET_AI(ai, afd, addr) \ 322 do { \ 323 /* external reference: pai, error, and label free */ \ 324 (ai) = get_ai(pai, (afd), (addr)); \ 325 if ((ai) == NULL) { \ 326 error = EAI_MEMORY; \ 327 goto free; \ 328 } \ 329 } while (/*CONSTCOND*/0) 330 331 #define GET_PORT(ai, serv) \ 332 do { \ 333 /* external reference: error and label free */ \ 334 error = get_port((ai), (serv), 0); \ 335 if (error != 0) \ 336 goto free; \ 337 } while (/*CONSTCOND*/0) 338 339 #define GET_CANONNAME(ai, str) \ 340 do { \ 341 /* external reference: pai, error and label free */ \ 342 error = get_canonname(pai, (ai), (str)); \ 343 if (error != 0) \ 344 goto free; \ 345 } while (/*CONSTCOND*/0) 346 347 #define ERR(err) \ 348 do { \ 349 /* external reference: error, and label bad */ \ 350 error = (err); \ 351 goto bad; \ 352 /*NOTREACHED*/ \ 353 } while (/*CONSTCOND*/0) 354 355 #define MATCH_FAMILY(x, y, w) \ 356 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 357 #define MATCH(x, y, w) \ 358 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 359 360 char * 361 gai_strerror(ecode) 362 int ecode; 363 { 364 struct ai_errlist *p; 365 366 for (p = ai_errlist; p->str; p++) { 367 if (p->code == ecode) 368 return (char *)p->str; 369 } 370 return "Unknown error"; 371 } 372 373 void 374 freeaddrinfo(ai) 375 struct addrinfo *ai; 376 { 377 struct addrinfo *next; 378 379 do { 380 next = ai->ai_next; 381 if (ai->ai_canonname) 382 free(ai->ai_canonname); 383 /* no need to free(ai->ai_addr) */ 384 free(ai); 385 ai = next; 386 } while (ai); 387 } 388 389 static int 390 str_isnumber(p) 391 const char *p; 392 { 393 char *ep; 394 395 if (*p == '\0') 396 return NO; 397 ep = NULL; 398 errno = 0; 399 (void)strtoul(p, &ep, 10); 400 if (errno == 0 && ep && *ep == '\0') 401 return YES; 402 else 403 return NO; 404 } 405 406 int 407 getaddrinfo(hostname, servname, hints, res) 408 const char *hostname, *servname; 409 const struct addrinfo *hints; 410 struct addrinfo **res; 411 { 412 struct addrinfo sentinel; 413 struct addrinfo *cur; 414 int error = 0; 415 struct addrinfo ai; 416 struct addrinfo ai0; 417 struct addrinfo *pai; 418 const struct explore *ex; 419 int numeric = 0; 420 421 memset(&sentinel, 0, sizeof(sentinel)); 422 cur = &sentinel; 423 pai = &ai; 424 pai->ai_flags = 0; 425 pai->ai_family = PF_UNSPEC; 426 pai->ai_socktype = ANY; 427 pai->ai_protocol = ANY; 428 pai->ai_addrlen = 0; 429 pai->ai_canonname = NULL; 430 pai->ai_addr = NULL; 431 pai->ai_next = NULL; 432 433 if (hostname == NULL && servname == NULL) 434 return EAI_NONAME; 435 if (hints) { 436 /* error check for hints */ 437 if (hints->ai_addrlen || hints->ai_canonname || 438 hints->ai_addr || hints->ai_next) 439 ERR(EAI_BADHINTS); /* xxx */ 440 if (hints->ai_flags & ~AI_MASK) 441 ERR(EAI_BADFLAGS); 442 switch (hints->ai_family) { 443 case PF_UNSPEC: 444 case PF_INET: 445 #ifdef INET6 446 case PF_INET6: 447 #endif 448 break; 449 default: 450 ERR(EAI_FAMILY); 451 } 452 memcpy(pai, hints, sizeof(*pai)); 453 454 /* 455 * if both socktype/protocol are specified, check if they 456 * are meaningful combination. 457 */ 458 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 459 for (ex = explore; ex->e_af >= 0; ex++) { 460 if (pai->ai_family != ex->e_af) 461 continue; 462 if (ex->e_socktype == ANY) 463 continue; 464 if (ex->e_protocol == ANY) 465 continue; 466 if (pai->ai_socktype == ex->e_socktype && 467 pai->ai_protocol != ex->e_protocol) { 468 ERR(EAI_BADHINTS); 469 } 470 } 471 } 472 } 473 474 /* 475 * post-2553: AI_ALL and AI_V4MAPPED are effective only against 476 * AF_INET6 query. They need to be ignored if specified in other 477 * occassions. 478 */ 479 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 480 case AI_V4MAPPED: 481 case AI_ALL | AI_V4MAPPED: 482 if (pai->ai_family != AF_INET6) 483 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 484 break; 485 case AI_ALL: 486 #if 1 487 /* illegal */ 488 ERR(EAI_BADFLAGS); 489 #else 490 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 491 #endif 492 break; 493 } 494 495 /* 496 * check for special cases. (1) numeric servname is disallowed if 497 * socktype/protocol are left unspecified. (2) servname is disallowed 498 * for raw and other inet{,6} sockets. 499 */ 500 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 501 #ifdef PF_INET6 502 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 503 #endif 504 ) { 505 ai0 = *pai; /* backup *pai */ 506 507 if (pai->ai_family == PF_UNSPEC) { 508 #ifdef PF_INET6 509 pai->ai_family = PF_INET6; 510 #else 511 pai->ai_family = PF_INET; 512 #endif 513 } 514 error = get_portmatch(pai, servname); 515 if (error) 516 ERR(error); 517 518 *pai = ai0; 519 } 520 521 ai0 = *pai; 522 523 /* NULL hostname, or numeric hostname */ 524 for (ex = explore; ex->e_af >= 0; ex++) { 525 *pai = ai0; 526 527 /* PF_UNSPEC entries are prepared for DNS queries only */ 528 if (ex->e_af == PF_UNSPEC) 529 continue; 530 531 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 532 continue; 533 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 534 continue; 535 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 536 continue; 537 538 if (pai->ai_family == PF_UNSPEC) 539 pai->ai_family = ex->e_af; 540 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 541 pai->ai_socktype = ex->e_socktype; 542 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 543 pai->ai_protocol = ex->e_protocol; 544 545 if (hostname == NULL) 546 error = explore_null(pai, servname, &cur->ai_next); 547 else 548 error = explore_numeric_scope(pai, hostname, servname, &cur->ai_next); 549 550 if (error) 551 goto free; 552 553 while (cur && cur->ai_next) 554 cur = cur->ai_next; 555 } 556 557 /* 558 * XXX 559 * If numreic representation of AF1 can be interpreted as FQDN 560 * representation of AF2, we need to think again about the code below. 561 */ 562 if (sentinel.ai_next) { 563 numeric = 1; 564 goto good; 565 } 566 567 if (hostname == NULL) 568 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 569 if (pai->ai_flags & AI_NUMERICHOST) 570 ERR(EAI_NONAME); 571 572 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 573 ERR(EAI_FAIL); 574 575 /* 576 * hostname as alphabetical name. 577 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 578 * outer loop by AFs. 579 */ 580 for (ex = explore; ex->e_af >= 0; ex++) { 581 *pai = ai0; 582 583 /* require exact match for family field */ 584 if (pai->ai_family != ex->e_af) 585 continue; 586 587 if (!MATCH(pai->ai_socktype, ex->e_socktype, 588 WILD_SOCKTYPE(ex))) { 589 continue; 590 } 591 if (!MATCH(pai->ai_protocol, ex->e_protocol, 592 WILD_PROTOCOL(ex))) { 593 continue; 594 } 595 596 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 597 pai->ai_socktype = ex->e_socktype; 598 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 599 pai->ai_protocol = ex->e_protocol; 600 601 error = explore_fqdn(pai, hostname, servname, 602 &cur->ai_next); 603 604 while (cur && cur->ai_next) 605 cur = cur->ai_next; 606 } 607 608 /* XXX inhibit errors if we have the result */ 609 if (sentinel.ai_next) 610 error = 0; 611 612 good: 613 /* 614 * ensure we return either: 615 * - error == 0, non-NULL *res 616 * - error != 0, NULL *res 617 */ 618 if (error == 0) { 619 if (sentinel.ai_next) { 620 /* 621 * If the returned entry is for an active connection, 622 * and the given name is not numeric, reorder the 623 * list, so that the application would try the list 624 * in the most efficient order. 625 */ 626 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 627 if (!numeric) 628 (void)reorder(&sentinel); 629 } 630 *res = sentinel.ai_next; 631 return SUCCESS; 632 } else 633 error = EAI_FAIL; 634 } 635 free: 636 bad: 637 if (sentinel.ai_next) 638 freeaddrinfo(sentinel.ai_next); 639 *res = NULL; 640 return error; 641 } 642 643 static int 644 reorder(sentinel) 645 struct addrinfo *sentinel; 646 { 647 struct addrinfo *ai, **aip; 648 struct ai_order *aio; 649 int i, n; 650 struct policyhead policyhead; 651 652 /* count the number of addrinfo elements for sorting. */ 653 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 654 ; 655 656 /* 657 * If the number is small enough, we can skip the reordering process. 658 */ 659 if (n <= 1) 660 return(n); 661 662 /* allocate a temporary array for sort and initialization of it. */ 663 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 664 return(n); /* give up reordering */ 665 memset(aio, 0, sizeof(*aio) * n); 666 667 /* retrieve address selection policy from the kernel */ 668 TAILQ_INIT(&policyhead); 669 if (!get_addrselectpolicy(&policyhead)) { 670 /* no policy is installed into kernel, we don't sort. */ 671 free(aio); 672 return (n); 673 } 674 675 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 676 aio[i].aio_ai = ai; 677 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 678 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 679 &policyhead); 680 } 681 682 /* perform sorting. */ 683 qsort(aio, n, sizeof(*aio), comp_dst); 684 685 /* reorder the addrinfo chain. */ 686 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 687 *aip = aio[i].aio_ai; 688 aip = &aio[i].aio_ai->ai_next; 689 } 690 *aip = NULL; 691 692 /* cleanup and return */ 693 free(aio); 694 free_addrselectpolicy(&policyhead); 695 return(n); 696 } 697 698 static int 699 get_addrselectpolicy(head) 700 struct policyhead *head; 701 { 702 #ifdef INET6 703 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 704 size_t l; 705 char *buf; 706 struct in6_addrpolicy *pol, *ep; 707 708 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 709 return (0); 710 if ((buf = malloc(l)) == NULL) 711 return (0); 712 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 713 free(buf); 714 return (0); 715 } 716 717 ep = (struct in6_addrpolicy *)(buf + l); 718 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 719 struct policyqueue *new; 720 721 if ((new = malloc(sizeof(*new))) == NULL) { 722 free_addrselectpolicy(head); /* make the list empty */ 723 break; 724 } 725 new->pc_policy = *pol; 726 TAILQ_INSERT_TAIL(head, new, pc_entry); 727 } 728 729 free(buf); 730 return (1); 731 #else 732 return (0); 733 #endif 734 } 735 736 static void 737 free_addrselectpolicy(head) 738 struct policyhead *head; 739 { 740 struct policyqueue *ent, *nent; 741 742 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 743 nent = TAILQ_NEXT(ent, pc_entry); 744 TAILQ_REMOVE(head, ent, pc_entry); 745 free(ent); 746 } 747 } 748 749 static struct policyqueue * 750 match_addrselectpolicy(addr, head) 751 struct sockaddr *addr; 752 struct policyhead *head; 753 { 754 #ifdef INET6 755 struct policyqueue *ent, *bestent = NULL; 756 struct in6_addrpolicy *pol; 757 int matchlen, bestmatchlen = -1; 758 u_char *mp, *ep, *k, *p, m; 759 struct sockaddr_in6 key; 760 761 switch(addr->sa_family) { 762 case AF_INET6: 763 key = *(struct sockaddr_in6 *)addr; 764 break; 765 case AF_INET: 766 /* convert the address into IPv4-mapped IPv6 address. */ 767 memset(&key, 0, sizeof(key)); 768 key.sin6_family = AF_INET6; 769 key.sin6_len = sizeof(key); 770 key.sin6_addr.s6_addr[10] = 0xff; 771 key.sin6_addr.s6_addr[11] = 0xff; 772 memcpy(&key.sin6_addr.s6_addr[12], 773 &((struct sockaddr_in *)addr)->sin_addr, 4); 774 break; 775 default: 776 return(NULL); 777 } 778 779 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 780 pol = &ent->pc_policy; 781 matchlen = 0; 782 783 mp = (u_char *)&pol->addrmask.sin6_addr; 784 ep = mp + 16; /* XXX: scope field? */ 785 k = (u_char *)&key.sin6_addr; 786 p = (u_char *)&pol->addr.sin6_addr; 787 for (; mp < ep && *mp; mp++, k++, p++) { 788 m = *mp; 789 if ((*k & m) != *p) 790 goto next; /* not match */ 791 if (m == 0xff) /* short cut for a typical case */ 792 matchlen += 8; 793 else { 794 while (m >= 0x80) { 795 matchlen++; 796 m <<= 1; 797 } 798 } 799 } 800 801 /* matched. check if this is better than the current best. */ 802 if (matchlen > bestmatchlen) { 803 bestent = ent; 804 bestmatchlen = matchlen; 805 } 806 807 next: 808 continue; 809 } 810 811 return(bestent); 812 #else 813 return(NULL); 814 #endif 815 816 } 817 818 static int 819 comp_dst(arg1, arg2) 820 const void *arg1, *arg2; 821 { 822 const struct ai_order *dst1 = arg1, *dst2 = arg2; 823 824 /* 825 * Rule 1: Avoid unusable destinations. 826 * XXX: we currently do not consider if an appropriate route exists. 827 */ 828 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 829 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 830 return(-1); 831 } 832 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 833 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 834 return(1); 835 } 836 837 /* Rule 2: Prefer matching scope. */ 838 if (dst1->aio_dstscope == dst1->aio_srcscope && 839 dst2->aio_dstscope != dst2->aio_srcscope) { 840 return(-1); 841 } 842 if (dst1->aio_dstscope != dst1->aio_srcscope && 843 dst2->aio_dstscope == dst2->aio_srcscope) { 844 return(1); 845 } 846 847 /* Rule 3: Avoid deprecated addresses. */ 848 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 849 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 850 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 851 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 852 return(-1); 853 } 854 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 855 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 856 return(1); 857 } 858 } 859 860 /* Rule 4: Prefer home addresses. */ 861 /* XXX: not implemented yet */ 862 863 /* Rule 5: Prefer matching label. */ 864 #ifdef INET6 865 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 866 dst1->aio_srcpolicy->pc_policy.label == 867 dst1->aio_dstpolicy->pc_policy.label && 868 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 869 dst2->aio_srcpolicy->pc_policy.label != 870 dst2->aio_dstpolicy->pc_policy.label)) { 871 return(-1); 872 } 873 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 874 dst2->aio_srcpolicy->pc_policy.label == 875 dst2->aio_dstpolicy->pc_policy.label && 876 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 877 dst1->aio_srcpolicy->pc_policy.label != 878 dst1->aio_dstpolicy->pc_policy.label)) { 879 return(1); 880 } 881 #endif 882 883 /* Rule 6: Prefer higher precedence. */ 884 #ifdef INET6 885 if (dst1->aio_dstpolicy && 886 (dst2->aio_dstpolicy == NULL || 887 dst1->aio_dstpolicy->pc_policy.preced > 888 dst2->aio_dstpolicy->pc_policy.preced)) { 889 return(-1); 890 } 891 if (dst2->aio_dstpolicy && 892 (dst1->aio_dstpolicy == NULL || 893 dst2->aio_dstpolicy->pc_policy.preced > 894 dst1->aio_dstpolicy->pc_policy.preced)) { 895 return(1); 896 } 897 #endif 898 899 /* Rule 7: Prefer native transport. */ 900 /* XXX: not implemented yet */ 901 902 /* Rule 8: Prefer smaller scope. */ 903 if (dst1->aio_dstscope >= 0 && 904 dst1->aio_dstscope < dst2->aio_dstscope) { 905 return(-1); 906 } 907 if (dst2->aio_dstscope >= 0 && 908 dst2->aio_dstscope < dst1->aio_dstscope) { 909 return(1); 910 } 911 912 /* 913 * Rule 9: Use longest matching prefix. 914 * We compare the match length in a same AF only. 915 */ 916 if (dst1->aio_ai->ai_addr->sa_family == 917 dst2->aio_ai->ai_addr->sa_family) { 918 if (dst1->aio_matchlen > dst2->aio_matchlen) { 919 return(-1); 920 } 921 if (dst1->aio_matchlen < dst2->aio_matchlen) { 922 return(1); 923 } 924 } 925 926 /* Rule 10: Otherwise, leave the order unchanged. */ 927 return(-1); 928 } 929 930 /* 931 * Copy from scope.c. 932 * XXX: we should standardize the functions and link them as standard 933 * library. 934 */ 935 static int 936 gai_addr2scopetype(sa) 937 struct sockaddr *sa; 938 { 939 #ifdef INET6 940 struct sockaddr_in6 *sa6; 941 #endif 942 struct sockaddr_in *sa4; 943 944 switch(sa->sa_family) { 945 #ifdef INET6 946 case AF_INET6: 947 sa6 = (struct sockaddr_in6 *)sa; 948 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 949 /* just use the scope field of the multicast address */ 950 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 951 } 952 /* 953 * Unicast addresses: map scope type to corresponding scope 954 * value defined for multcast addresses. 955 * XXX: hardcoded scope type values are bad... 956 */ 957 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 958 return(1); /* node local scope */ 959 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 960 return(2); /* link-local scope */ 961 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 962 return(5); /* site-local scope */ 963 return(14); /* global scope */ 964 break; 965 #endif 966 case AF_INET: 967 /* 968 * IPv4 pseudo scoping according to RFC 3484. 969 */ 970 sa4 = (struct sockaddr_in *)sa; 971 /* IPv4 autoconfiguration addresses have link-local scope. */ 972 if (((u_char *)&sa4->sin_addr)[0] == 169 && 973 ((u_char *)&sa4->sin_addr)[1] == 254) 974 return(2); 975 /* Private addresses have site-local scope. */ 976 if (((u_char *)&sa4->sin_addr)[0] == 10 || 977 (((u_char *)&sa4->sin_addr)[0] == 172 && 978 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 979 (((u_char *)&sa4->sin_addr)[0] == 192 && 980 ((u_char *)&sa4->sin_addr)[1] == 168)) 981 return(5); 982 /* Loopback addresses have link-local scope. */ 983 if (((u_char *)&sa4->sin_addr)[0] == 127) 984 return(2); 985 return(14); 986 break; 987 default: 988 errno = EAFNOSUPPORT; /* is this a good error? */ 989 return(-1); 990 } 991 } 992 993 /* 994 * hostname == NULL. 995 * passive socket -> anyaddr (0.0.0.0 or ::) 996 * non-passive socket -> localhost (127.0.0.1 or ::1) 997 */ 998 static int 999 explore_null(pai, servname, res) 1000 const struct addrinfo *pai; 1001 const char *servname; 1002 struct addrinfo **res; 1003 { 1004 int s; 1005 const struct afd *afd; 1006 struct addrinfo *cur; 1007 struct addrinfo sentinel; 1008 int error; 1009 1010 *res = NULL; 1011 sentinel.ai_next = NULL; 1012 cur = &sentinel; 1013 1014 /* 1015 * filter out AFs that are not supported by the kernel 1016 * XXX errno? 1017 */ 1018 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1019 if (s < 0) { 1020 if (errno != EMFILE) 1021 return 0; 1022 } else 1023 _close(s); 1024 1025 /* 1026 * if the servname does not match socktype/protocol, ignore it. 1027 */ 1028 if (get_portmatch(pai, servname) != 0) 1029 return 0; 1030 1031 afd = find_afd(pai->ai_family); 1032 if (afd == NULL) 1033 return 0; 1034 1035 if (pai->ai_flags & AI_PASSIVE) { 1036 GET_AI(cur->ai_next, afd, afd->a_addrany); 1037 /* xxx meaningless? 1038 * GET_CANONNAME(cur->ai_next, "anyaddr"); 1039 */ 1040 GET_PORT(cur->ai_next, servname); 1041 } else { 1042 GET_AI(cur->ai_next, afd, afd->a_loopback); 1043 /* xxx meaningless? 1044 * GET_CANONNAME(cur->ai_next, "localhost"); 1045 */ 1046 GET_PORT(cur->ai_next, servname); 1047 } 1048 cur = cur->ai_next; 1049 1050 *res = sentinel.ai_next; 1051 return 0; 1052 1053 free: 1054 if (sentinel.ai_next) 1055 freeaddrinfo(sentinel.ai_next); 1056 return error; 1057 } 1058 1059 /* 1060 * numeric hostname 1061 */ 1062 static int 1063 explore_numeric(pai, hostname, servname, res) 1064 const struct addrinfo *pai; 1065 const char *hostname; 1066 const char *servname; 1067 struct addrinfo **res; 1068 { 1069 const struct afd *afd; 1070 struct addrinfo *cur; 1071 struct addrinfo sentinel; 1072 int error; 1073 char pton[PTON_MAX]; 1074 1075 *res = NULL; 1076 sentinel.ai_next = NULL; 1077 cur = &sentinel; 1078 1079 /* 1080 * if the servname does not match socktype/protocol, ignore it. 1081 */ 1082 if (get_portmatch(pai, servname) != 0) 1083 return 0; 1084 1085 afd = find_afd(pai->ai_family); 1086 if (afd == NULL) 1087 return 0; 1088 1089 switch (afd->a_af) { 1090 #if 1 /*X/Open spec*/ 1091 case AF_INET: 1092 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 1093 if (pai->ai_family == afd->a_af || 1094 pai->ai_family == PF_UNSPEC /*?*/) { 1095 GET_AI(cur->ai_next, afd, pton); 1096 GET_PORT(cur->ai_next, servname); 1097 while (cur && cur->ai_next) 1098 cur = cur->ai_next; 1099 } else 1100 ERR(EAI_FAMILY); /*xxx*/ 1101 } 1102 break; 1103 #endif 1104 default: 1105 if (inet_pton(afd->a_af, hostname, pton) == 1) { 1106 if (pai->ai_family == afd->a_af || 1107 pai->ai_family == PF_UNSPEC /*?*/) { 1108 GET_AI(cur->ai_next, afd, pton); 1109 GET_PORT(cur->ai_next, servname); 1110 while (cur && cur->ai_next) 1111 cur = cur->ai_next; 1112 } else 1113 ERR(EAI_FAMILY); /* XXX */ 1114 } 1115 break; 1116 } 1117 1118 *res = sentinel.ai_next; 1119 return 0; 1120 1121 free: 1122 bad: 1123 if (sentinel.ai_next) 1124 freeaddrinfo(sentinel.ai_next); 1125 return error; 1126 } 1127 1128 /* 1129 * numeric hostname with scope 1130 */ 1131 static int 1132 explore_numeric_scope(pai, hostname, servname, res) 1133 const struct addrinfo *pai; 1134 const char *hostname; 1135 const char *servname; 1136 struct addrinfo **res; 1137 { 1138 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 1139 return explore_numeric(pai, hostname, servname, res); 1140 #else 1141 const struct afd *afd; 1142 struct addrinfo *cur; 1143 int error; 1144 char *cp, *hostname2 = NULL, *scope, *addr; 1145 struct sockaddr_in6 *sin6; 1146 1147 /* 1148 * if the servname does not match socktype/protocol, ignore it. 1149 */ 1150 if (get_portmatch(pai, servname) != 0) 1151 return 0; 1152 1153 afd = find_afd(pai->ai_family); 1154 if (afd == NULL) 1155 return 0; 1156 1157 if (!afd->a_scoped) 1158 return explore_numeric(pai, hostname, servname, res); 1159 1160 cp = strchr(hostname, SCOPE_DELIMITER); 1161 if (cp == NULL) 1162 return explore_numeric(pai, hostname, servname, res); 1163 1164 /* 1165 * Handle special case of <scoped_address><delimiter><scope id> 1166 */ 1167 hostname2 = strdup(hostname); 1168 if (hostname2 == NULL) 1169 return EAI_MEMORY; 1170 /* terminate at the delimiter */ 1171 hostname2[cp - hostname] = '\0'; 1172 addr = hostname2; 1173 scope = cp + 1; 1174 1175 error = explore_numeric(pai, addr, servname, res); 1176 if (error == 0) { 1177 u_int32_t scopeid; 1178 1179 for (cur = *res; cur; cur = cur->ai_next) { 1180 if (cur->ai_family != AF_INET6) 1181 continue; 1182 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1183 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1184 free(hostname2); 1185 return(EAI_NONAME); /* XXX: is return OK? */ 1186 } 1187 sin6->sin6_scope_id = scopeid; 1188 } 1189 } 1190 1191 free(hostname2); 1192 1193 return error; 1194 #endif 1195 } 1196 1197 static int 1198 get_canonname(pai, ai, str) 1199 const struct addrinfo *pai; 1200 struct addrinfo *ai; 1201 const char *str; 1202 { 1203 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1204 ai->ai_canonname = (char *)malloc(strlen(str) + 1); 1205 if (ai->ai_canonname == NULL) 1206 return EAI_MEMORY; 1207 strlcpy(ai->ai_canonname, str, strlen(str) + 1); 1208 } 1209 return 0; 1210 } 1211 1212 static struct addrinfo * 1213 get_ai(pai, afd, addr) 1214 const struct addrinfo *pai; 1215 const struct afd *afd; 1216 const char *addr; 1217 { 1218 char *p; 1219 struct addrinfo *ai; 1220 #ifdef FAITH 1221 struct in6_addr faith_prefix; 1222 char *fp_str; 1223 int translate = 0; 1224 #endif 1225 1226 #ifdef FAITH 1227 /* 1228 * Transfrom an IPv4 addr into a special IPv6 addr format for 1229 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1230 * 1231 * +-----------------------------------+------------+ 1232 * | faith prefix part (12 bytes) | embedded | 1233 * | | IPv4 addr part (4 bytes) 1234 * +-----------------------------------+------------+ 1235 * 1236 * faith prefix part is specified as ascii IPv6 addr format 1237 * in environmental variable GAI. 1238 * For FAITH to work correctly, routing to faith prefix must be 1239 * setup toward a machine where a FAITH daemon operates. 1240 * Also, the machine must enable some mechanizm 1241 * (e.g. faith interface hack) to divert those packet with 1242 * faith prefixed destination addr to user-land FAITH daemon. 1243 */ 1244 fp_str = getenv("GAI"); 1245 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1246 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1247 u_int32_t v4a; 1248 u_int8_t v4a_top; 1249 1250 memcpy(&v4a, addr, sizeof v4a); 1251 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1252 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1253 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1254 afd = &afdl[N_INET6]; 1255 memcpy(&faith_prefix.s6_addr[12], addr, 1256 sizeof(struct in_addr)); 1257 translate = 1; 1258 } 1259 } 1260 #endif 1261 1262 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1263 + (afd->a_socklen)); 1264 if (ai == NULL) 1265 return NULL; 1266 1267 memcpy(ai, pai, sizeof(struct addrinfo)); 1268 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1269 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1270 ai->ai_addr->sa_len = afd->a_socklen; 1271 ai->ai_addrlen = afd->a_socklen; 1272 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1273 p = (char *)(void *)(ai->ai_addr); 1274 #ifdef FAITH 1275 if (translate == 1) 1276 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1277 else 1278 #endif 1279 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1280 return ai; 1281 } 1282 1283 static int 1284 get_portmatch(ai, servname) 1285 const struct addrinfo *ai; 1286 const char *servname; 1287 { 1288 1289 /* get_port does not touch first argument. when matchonly == 1. */ 1290 /* LINTED const cast */ 1291 return get_port((struct addrinfo *)ai, servname, 1); 1292 } 1293 1294 static int 1295 get_port(ai, servname, matchonly) 1296 struct addrinfo *ai; 1297 const char *servname; 1298 int matchonly; 1299 { 1300 const char *proto; 1301 struct servent *sp; 1302 int port; 1303 int allownumeric; 1304 1305 if (servname == NULL) 1306 return 0; 1307 switch (ai->ai_family) { 1308 case AF_INET: 1309 #ifdef AF_INET6 1310 case AF_INET6: 1311 #endif 1312 break; 1313 default: 1314 return 0; 1315 } 1316 1317 switch (ai->ai_socktype) { 1318 case SOCK_RAW: 1319 return EAI_SERVICE; 1320 case SOCK_DGRAM: 1321 case SOCK_STREAM: 1322 allownumeric = 1; 1323 break; 1324 case ANY: 1325 allownumeric = 0; 1326 break; 1327 default: 1328 return EAI_SOCKTYPE; 1329 } 1330 1331 if (str_isnumber(servname)) { 1332 if (!allownumeric) 1333 return EAI_SERVICE; 1334 port = atoi(servname); 1335 if (port < 0 || port > 65535) 1336 return EAI_SERVICE; 1337 port = htons(port); 1338 } else { 1339 switch (ai->ai_socktype) { 1340 case SOCK_DGRAM: 1341 proto = "udp"; 1342 break; 1343 case SOCK_STREAM: 1344 proto = "tcp"; 1345 break; 1346 default: 1347 proto = NULL; 1348 break; 1349 } 1350 1351 THREAD_LOCK(); 1352 if ((sp = getservbyname(servname, proto)) == NULL) { 1353 THREAD_UNLOCK(); 1354 return EAI_SERVICE; 1355 } 1356 port = sp->s_port; 1357 THREAD_UNLOCK(); 1358 } 1359 1360 if (!matchonly) { 1361 switch (ai->ai_family) { 1362 case AF_INET: 1363 ((struct sockaddr_in *)(void *) 1364 ai->ai_addr)->sin_port = port; 1365 break; 1366 #ifdef INET6 1367 case AF_INET6: 1368 ((struct sockaddr_in6 *)(void *) 1369 ai->ai_addr)->sin6_port = port; 1370 break; 1371 #endif 1372 } 1373 } 1374 1375 return 0; 1376 } 1377 1378 static const struct afd * 1379 find_afd(af) 1380 int af; 1381 { 1382 const struct afd *afd; 1383 1384 if (af == PF_UNSPEC) 1385 return NULL; 1386 for (afd = afdl; afd->a_af; afd++) { 1387 if (afd->a_af == af) 1388 return afd; 1389 } 1390 return NULL; 1391 } 1392 1393 /* 1394 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1395 * will take care of it. 1396 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1397 * if the code is right or not. 1398 * 1399 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1400 * _dns_getaddrinfo. 1401 */ 1402 static int 1403 addrconfig(pai) 1404 struct addrinfo *pai; 1405 { 1406 int s, af; 1407 1408 /* 1409 * TODO: 1410 * Note that implementation dependent test for address 1411 * configuration should be done everytime called 1412 * (or apropriate interval), 1413 * because addresses will be dynamically assigned or deleted. 1414 */ 1415 af = pai->ai_family; 1416 if (af == AF_UNSPEC) { 1417 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1418 af = AF_INET; 1419 else { 1420 _close(s); 1421 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1422 af = AF_INET6; 1423 else 1424 _close(s); 1425 } 1426 } 1427 if (af != AF_UNSPEC) { 1428 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1429 return 0; 1430 _close(s); 1431 } 1432 pai->ai_family = af; 1433 return 1; 1434 } 1435 1436 #ifdef INET6 1437 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1438 static int 1439 ip6_str2scopeid(scope, sin6, scopeid) 1440 char *scope; 1441 struct sockaddr_in6 *sin6; 1442 u_int32_t *scopeid; 1443 { 1444 u_long lscopeid; 1445 struct in6_addr *a6; 1446 char *ep; 1447 1448 a6 = &sin6->sin6_addr; 1449 1450 /* empty scopeid portion is invalid */ 1451 if (*scope == '\0') 1452 return -1; 1453 1454 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1455 /* 1456 * We currently assume a one-to-one mapping between links 1457 * and interfaces, so we simply use interface indices for 1458 * like-local scopes. 1459 */ 1460 *scopeid = if_nametoindex(scope); 1461 if (*scopeid == 0) 1462 goto trynumeric; 1463 return 0; 1464 } 1465 1466 /* still unclear about literal, allow numeric only - placeholder */ 1467 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1468 goto trynumeric; 1469 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1470 goto trynumeric; 1471 else 1472 goto trynumeric; /* global */ 1473 1474 /* try to convert to a numeric id as a last resort */ 1475 trynumeric: 1476 errno = 0; 1477 lscopeid = strtoul(scope, &ep, 10); 1478 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1479 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1480 return 0; 1481 else 1482 return -1; 1483 } 1484 #endif 1485 1486 /* 1487 * FQDN hostname, DNS lookup 1488 */ 1489 static int 1490 explore_fqdn(pai, hostname, servname, res) 1491 const struct addrinfo *pai; 1492 const char *hostname; 1493 const char *servname; 1494 struct addrinfo **res; 1495 { 1496 struct addrinfo *result; 1497 struct addrinfo *cur; 1498 int error = 0; 1499 static const ns_dtab dtab[] = { 1500 NS_FILES_CB(_files_getaddrinfo, NULL) 1501 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1502 NS_NIS_CB(_yp_getaddrinfo, NULL) 1503 { 0 } 1504 }; 1505 1506 result = NULL; 1507 1508 /* 1509 * if the servname does not match socktype/protocol, ignore it. 1510 */ 1511 if (get_portmatch(pai, servname) != 0) 1512 return 0; 1513 1514 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1515 default_dns_files, hostname, pai)) { 1516 case NS_TRYAGAIN: 1517 error = EAI_AGAIN; 1518 goto free; 1519 case NS_UNAVAIL: 1520 error = EAI_FAIL; 1521 goto free; 1522 case NS_NOTFOUND: 1523 error = EAI_NONAME; 1524 goto free; 1525 case NS_SUCCESS: 1526 error = 0; 1527 for (cur = result; cur; cur = cur->ai_next) { 1528 GET_PORT(cur, servname); 1529 /* canonname should be filled already */ 1530 } 1531 break; 1532 } 1533 1534 *res = result; 1535 1536 return 0; 1537 1538 free: 1539 if (result) 1540 freeaddrinfo(result); 1541 return error; 1542 } 1543 1544 #ifdef DEBUG 1545 static const char AskedForGot[] = 1546 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1547 #endif 1548 static FILE *hostf = NULL; 1549 1550 static struct addrinfo * 1551 getanswer(answer, anslen, qname, qtype, pai) 1552 const querybuf *answer; 1553 int anslen; 1554 const char *qname; 1555 int qtype; 1556 const struct addrinfo *pai; 1557 { 1558 struct addrinfo sentinel, *cur; 1559 struct addrinfo ai; 1560 const struct afd *afd; 1561 char *canonname; 1562 const HEADER *hp; 1563 const u_char *cp; 1564 int n; 1565 const u_char *eom; 1566 char *bp, *ep; 1567 int type, class, ancount, qdcount; 1568 int haveanswer, had_error; 1569 char tbuf[MAXDNAME]; 1570 int (*name_ok)(const char *); 1571 char hostbuf[8*1024]; 1572 1573 memset(&sentinel, 0, sizeof(sentinel)); 1574 cur = &sentinel; 1575 1576 canonname = NULL; 1577 eom = answer->buf + anslen; 1578 switch (qtype) { 1579 case T_A: 1580 case T_AAAA: 1581 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1582 name_ok = res_hnok; 1583 break; 1584 default: 1585 return (NULL); /* XXX should be abort(); */ 1586 } 1587 /* 1588 * find first satisfactory answer 1589 */ 1590 hp = &answer->hdr; 1591 ancount = ntohs(hp->ancount); 1592 qdcount = ntohs(hp->qdcount); 1593 bp = hostbuf; 1594 ep = hostbuf + sizeof hostbuf; 1595 cp = answer->buf + HFIXEDSZ; 1596 if (qdcount != 1) { 1597 h_errno = NO_RECOVERY; 1598 return (NULL); 1599 } 1600 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1601 if ((n < 0) || !(*name_ok)(bp)) { 1602 h_errno = NO_RECOVERY; 1603 return (NULL); 1604 } 1605 cp += n + QFIXEDSZ; 1606 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1607 /* res_send() has already verified that the query name is the 1608 * same as the one we sent; this just gets the expanded name 1609 * (i.e., with the succeeding search-domain tacked on). 1610 */ 1611 n = strlen(bp) + 1; /* for the \0 */ 1612 if (n >= MAXHOSTNAMELEN) { 1613 h_errno = NO_RECOVERY; 1614 return (NULL); 1615 } 1616 canonname = bp; 1617 bp += n; 1618 /* The qname can be abbreviated, but h_name is now absolute. */ 1619 qname = canonname; 1620 } 1621 haveanswer = 0; 1622 had_error = 0; 1623 while (ancount-- > 0 && cp < eom && !had_error) { 1624 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1625 if ((n < 0) || !(*name_ok)(bp)) { 1626 had_error++; 1627 continue; 1628 } 1629 cp += n; /* name */ 1630 type = _getshort(cp); 1631 cp += INT16SZ; /* type */ 1632 class = _getshort(cp); 1633 cp += INT16SZ + INT32SZ; /* class, TTL */ 1634 n = _getshort(cp); 1635 cp += INT16SZ; /* len */ 1636 if (class != C_IN) { 1637 /* XXX - debug? syslog? */ 1638 cp += n; 1639 continue; /* XXX - had_error++ ? */ 1640 } 1641 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1642 type == T_CNAME) { 1643 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1644 if ((n < 0) || !(*name_ok)(tbuf)) { 1645 had_error++; 1646 continue; 1647 } 1648 cp += n; 1649 /* Get canonical name. */ 1650 n = strlen(tbuf) + 1; /* for the \0 */ 1651 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1652 had_error++; 1653 continue; 1654 } 1655 strlcpy(bp, tbuf, ep - bp); 1656 canonname = bp; 1657 bp += n; 1658 continue; 1659 } 1660 if (qtype == T_ANY) { 1661 if (!(type == T_A || type == T_AAAA)) { 1662 cp += n; 1663 continue; 1664 } 1665 } else if (type != qtype) { 1666 #ifdef DEBUG 1667 if (type != T_KEY && type != T_SIG) 1668 syslog(LOG_NOTICE|LOG_AUTH, 1669 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1670 qname, p_class(C_IN), p_type(qtype), 1671 p_type(type)); 1672 #endif 1673 cp += n; 1674 continue; /* XXX - had_error++ ? */ 1675 } 1676 switch (type) { 1677 case T_A: 1678 case T_AAAA: 1679 if (strcasecmp(canonname, bp) != 0) { 1680 #ifdef DEBUG 1681 syslog(LOG_NOTICE|LOG_AUTH, 1682 AskedForGot, canonname, bp); 1683 #endif 1684 cp += n; 1685 continue; /* XXX - had_error++ ? */ 1686 } 1687 if (type == T_A && n != INADDRSZ) { 1688 cp += n; 1689 continue; 1690 } 1691 if (type == T_AAAA && n != IN6ADDRSZ) { 1692 cp += n; 1693 continue; 1694 } 1695 #ifdef FILTER_V4MAPPED 1696 if (type == T_AAAA) { 1697 struct in6_addr in6; 1698 memcpy(&in6, cp, sizeof(in6)); 1699 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1700 cp += n; 1701 continue; 1702 } 1703 } 1704 #endif 1705 if (!haveanswer) { 1706 int nn; 1707 1708 canonname = bp; 1709 nn = strlen(bp) + 1; /* for the \0 */ 1710 bp += nn; 1711 } 1712 1713 /* don't overwrite pai */ 1714 ai = *pai; 1715 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1716 afd = find_afd(ai.ai_family); 1717 if (afd == NULL) { 1718 cp += n; 1719 continue; 1720 } 1721 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1722 if (cur->ai_next == NULL) 1723 had_error++; 1724 while (cur && cur->ai_next) 1725 cur = cur->ai_next; 1726 cp += n; 1727 break; 1728 default: 1729 abort(); 1730 } 1731 if (!had_error) 1732 haveanswer++; 1733 } 1734 if (haveanswer) { 1735 #if defined(RESOLVSORT) 1736 /* 1737 * We support only IPv4 address for backward 1738 * compatibility against gethostbyname(3). 1739 */ 1740 if (_res.nsort && qtype == T_A) { 1741 if (addr4sort(&sentinel) < 0) { 1742 freeaddrinfo(sentinel.ai_next); 1743 h_errno = NO_RECOVERY; 1744 return NULL; 1745 } 1746 } 1747 #endif /*RESOLVSORT*/ 1748 if (!canonname) 1749 (void)get_canonname(pai, sentinel.ai_next, qname); 1750 else 1751 (void)get_canonname(pai, sentinel.ai_next, canonname); 1752 h_errno = NETDB_SUCCESS; 1753 return sentinel.ai_next; 1754 } 1755 1756 h_errno = NO_RECOVERY; 1757 return NULL; 1758 } 1759 1760 #ifdef RESOLVSORT 1761 struct addr_ptr { 1762 struct addrinfo *ai; 1763 int aval; 1764 }; 1765 1766 static int 1767 addr4sort(struct addrinfo *sentinel) 1768 { 1769 struct addrinfo *ai; 1770 struct addr_ptr *addrs, addr; 1771 struct sockaddr_in *sin; 1772 int naddrs, i, j; 1773 int needsort = 0; 1774 1775 if (!sentinel) 1776 return -1; 1777 naddrs = 0; 1778 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1779 naddrs++; 1780 if (naddrs < 2) 1781 return 0; /* We don't need sorting. */ 1782 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1783 return -1; 1784 i = 0; 1785 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1786 sin = (struct sockaddr_in *)ai->ai_addr; 1787 for (j = 0; (unsigned)j < _res.nsort; j++) { 1788 if (_res.sort_list[j].addr.s_addr == 1789 (sin->sin_addr.s_addr & _res.sort_list[j].mask)) 1790 break; 1791 } 1792 addrs[i].ai = ai; 1793 addrs[i].aval = j; 1794 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1795 needsort = i; 1796 i++; 1797 } 1798 if (!needsort) { 1799 free(addrs); 1800 return 0; 1801 } 1802 1803 while (needsort < naddrs) { 1804 for (j = needsort - 1; j >= 0; j--) { 1805 if (addrs[j].aval > addrs[j+1].aval) { 1806 addr = addrs[j]; 1807 addrs[j] = addrs[j + 1]; 1808 addrs[j + 1] = addr; 1809 } else 1810 break; 1811 } 1812 needsort++; 1813 } 1814 1815 ai = sentinel; 1816 for (i = 0; i < naddrs; ++i) { 1817 ai->ai_next = addrs[i].ai; 1818 ai = ai->ai_next; 1819 } 1820 ai->ai_next = NULL; 1821 free(addrs); 1822 return 0; 1823 } 1824 #endif /*RESOLVSORT*/ 1825 1826 /*ARGSUSED*/ 1827 static int 1828 _dns_getaddrinfo(rv, cb_data, ap) 1829 void *rv; 1830 void *cb_data; 1831 va_list ap; 1832 { 1833 struct addrinfo *ai; 1834 querybuf *buf, *buf2; 1835 const char *name; 1836 const struct addrinfo *pai; 1837 struct addrinfo sentinel, *cur; 1838 struct res_target q, q2; 1839 1840 name = va_arg(ap, char *); 1841 pai = va_arg(ap, const struct addrinfo *); 1842 1843 memset(&q, 0, sizeof(q2)); 1844 memset(&q2, 0, sizeof(q2)); 1845 memset(&sentinel, 0, sizeof(sentinel)); 1846 cur = &sentinel; 1847 1848 buf = malloc(sizeof(*buf)); 1849 if (!buf) { 1850 h_errno = NETDB_INTERNAL; 1851 return NS_NOTFOUND; 1852 } 1853 buf2 = malloc(sizeof(*buf2)); 1854 if (!buf2) { 1855 free(buf); 1856 h_errno = NETDB_INTERNAL; 1857 return NS_NOTFOUND; 1858 } 1859 1860 switch (pai->ai_family) { 1861 case AF_UNSPEC: 1862 /* prefer IPv6 */ 1863 q.name = name; 1864 q.qclass = C_IN; 1865 q.qtype = T_AAAA; 1866 q.answer = buf->buf; 1867 q.anslen = sizeof(buf->buf); 1868 q.next = &q2; 1869 q2.name = name; 1870 q2.qclass = C_IN; 1871 q2.qtype = T_A; 1872 q2.answer = buf2->buf; 1873 q2.anslen = sizeof(buf2->buf); 1874 break; 1875 case AF_INET: 1876 q.name = name; 1877 q.qclass = C_IN; 1878 q.qtype = T_A; 1879 q.answer = buf->buf; 1880 q.anslen = sizeof(buf->buf); 1881 break; 1882 case AF_INET6: 1883 q.name = name; 1884 q.qclass = C_IN; 1885 q.qtype = T_AAAA; 1886 q.answer = buf->buf; 1887 q.anslen = sizeof(buf->buf); 1888 break; 1889 default: 1890 free(buf); 1891 free(buf2); 1892 return NS_UNAVAIL; 1893 } 1894 if (res_searchN(name, &q) < 0) { 1895 free(buf); 1896 free(buf2); 1897 return NS_NOTFOUND; 1898 } 1899 ai = getanswer(buf, q.n, q.name, q.qtype, pai); 1900 if (ai) { 1901 cur->ai_next = ai; 1902 while (cur && cur->ai_next) 1903 cur = cur->ai_next; 1904 } 1905 if (q.next) { 1906 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai); 1907 if (ai) 1908 cur->ai_next = ai; 1909 } 1910 free(buf); 1911 free(buf2); 1912 if (sentinel.ai_next == NULL) 1913 switch (h_errno) { 1914 case HOST_NOT_FOUND: 1915 return NS_NOTFOUND; 1916 case TRY_AGAIN: 1917 return NS_TRYAGAIN; 1918 default: 1919 return NS_UNAVAIL; 1920 } 1921 *((struct addrinfo **)rv) = sentinel.ai_next; 1922 return NS_SUCCESS; 1923 } 1924 1925 static void 1926 _sethtent() 1927 { 1928 if (!hostf) 1929 hostf = fopen(_PATH_HOSTS, "r" ); 1930 else 1931 rewind(hostf); 1932 } 1933 1934 static void 1935 _endhtent() 1936 { 1937 if (hostf) { 1938 (void) fclose(hostf); 1939 hostf = NULL; 1940 } 1941 } 1942 1943 static struct addrinfo * 1944 _gethtent(name, pai) 1945 const char *name; 1946 const struct addrinfo *pai; 1947 { 1948 char *p; 1949 char *cp, *tname, *cname; 1950 struct addrinfo hints, *res0, *res; 1951 int error; 1952 const char *addr; 1953 char hostbuf[8*1024]; 1954 1955 if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) 1956 return (NULL); 1957 again: 1958 if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) 1959 return (NULL); 1960 if (*p == '#') 1961 goto again; 1962 if (!(cp = strpbrk(p, "#\n"))) 1963 goto again; 1964 *cp = '\0'; 1965 if (!(cp = strpbrk(p, " \t"))) 1966 goto again; 1967 *cp++ = '\0'; 1968 addr = p; 1969 cname = NULL; 1970 /* if this is not something we're looking for, skip it. */ 1971 while (cp && *cp) { 1972 if (*cp == ' ' || *cp == '\t') { 1973 cp++; 1974 continue; 1975 } 1976 tname = cp; 1977 if (cname == NULL) 1978 cname = cp; 1979 if ((cp = strpbrk(cp, " \t")) != NULL) 1980 *cp++ = '\0'; 1981 if (strcasecmp(name, tname) == 0) 1982 goto found; 1983 } 1984 goto again; 1985 1986 found: 1987 /* we should not glob socktype/protocol here */ 1988 memset(&hints, 0, sizeof(hints)); 1989 hints.ai_family = pai->ai_family; 1990 hints.ai_socktype = SOCK_DGRAM; 1991 hints.ai_protocol = 0; 1992 hints.ai_flags = AI_NUMERICHOST; 1993 error = getaddrinfo(addr, "0", &hints, &res0); 1994 if (error) 1995 goto again; 1996 #ifdef FILTER_V4MAPPED 1997 /* XXX should check all items in the chain */ 1998 if (res0->ai_family == AF_INET6 && 1999 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2000 freeaddrinfo(res0); 2001 goto again; 2002 } 2003 #endif 2004 for (res = res0; res; res = res->ai_next) { 2005 /* cover it up */ 2006 res->ai_flags = pai->ai_flags; 2007 res->ai_socktype = pai->ai_socktype; 2008 res->ai_protocol = pai->ai_protocol; 2009 2010 if (pai->ai_flags & AI_CANONNAME) { 2011 if (get_canonname(pai, res, cname) != 0) { 2012 freeaddrinfo(res0); 2013 goto again; 2014 } 2015 } 2016 } 2017 return res0; 2018 } 2019 2020 /*ARGSUSED*/ 2021 static int 2022 _files_getaddrinfo(rv, cb_data, ap) 2023 void *rv; 2024 void *cb_data; 2025 va_list ap; 2026 { 2027 const char *name; 2028 const struct addrinfo *pai; 2029 struct addrinfo sentinel, *cur; 2030 struct addrinfo *p; 2031 2032 name = va_arg(ap, char *); 2033 pai = va_arg(ap, struct addrinfo *); 2034 2035 memset(&sentinel, 0, sizeof(sentinel)); 2036 cur = &sentinel; 2037 2038 THREAD_LOCK(); 2039 _sethtent(); 2040 while ((p = _gethtent(name, pai)) != NULL) { 2041 cur->ai_next = p; 2042 while (cur && cur->ai_next) 2043 cur = cur->ai_next; 2044 } 2045 _endhtent(); 2046 THREAD_UNLOCK(); 2047 2048 *((struct addrinfo **)rv) = sentinel.ai_next; 2049 if (sentinel.ai_next == NULL) 2050 return NS_NOTFOUND; 2051 return NS_SUCCESS; 2052 } 2053 2054 #ifdef YP 2055 static char *__ypdomain; 2056 2057 /*ARGSUSED*/ 2058 static struct addrinfo * 2059 _yphostent(line, pai) 2060 char *line; 2061 const struct addrinfo *pai; 2062 { 2063 struct addrinfo sentinel, *cur; 2064 struct addrinfo hints, *res, *res0; 2065 int error; 2066 char *p = line; 2067 const char *addr, *canonname; 2068 char *nextline; 2069 char *cp; 2070 2071 addr = canonname = NULL; 2072 2073 memset(&sentinel, 0, sizeof(sentinel)); 2074 cur = &sentinel; 2075 2076 nextline: 2077 /* terminate line */ 2078 cp = strchr(p, '\n'); 2079 if (cp) { 2080 *cp++ = '\0'; 2081 nextline = cp; 2082 } else 2083 nextline = NULL; 2084 2085 cp = strpbrk(p, " \t"); 2086 if (cp == NULL) { 2087 if (canonname == NULL) 2088 return (NULL); 2089 else 2090 goto done; 2091 } 2092 *cp++ = '\0'; 2093 2094 addr = p; 2095 2096 while (cp && *cp) { 2097 if (*cp == ' ' || *cp == '\t') { 2098 cp++; 2099 continue; 2100 } 2101 if (!canonname) 2102 canonname = cp; 2103 if ((cp = strpbrk(cp, " \t")) != NULL) 2104 *cp++ = '\0'; 2105 } 2106 2107 hints = *pai; 2108 hints.ai_flags = AI_NUMERICHOST; 2109 error = getaddrinfo(addr, NULL, &hints, &res0); 2110 if (error == 0) { 2111 for (res = res0; res; res = res->ai_next) { 2112 /* cover it up */ 2113 res->ai_flags = pai->ai_flags; 2114 2115 if (pai->ai_flags & AI_CANONNAME) 2116 (void)get_canonname(pai, res, canonname); 2117 } 2118 } else 2119 res0 = NULL; 2120 if (res0) { 2121 cur->ai_next = res0; 2122 while (cur && cur->ai_next) 2123 cur = cur->ai_next; 2124 } 2125 2126 if (nextline) { 2127 p = nextline; 2128 goto nextline; 2129 } 2130 2131 done: 2132 return sentinel.ai_next; 2133 } 2134 2135 /*ARGSUSED*/ 2136 static int 2137 _yp_getaddrinfo(rv, cb_data, ap) 2138 void *rv; 2139 void *cb_data; 2140 va_list ap; 2141 { 2142 struct addrinfo sentinel, *cur; 2143 struct addrinfo *ai = NULL; 2144 static char *__ypcurrent; 2145 int __ypcurrentlen, r; 2146 const char *name; 2147 const struct addrinfo *pai; 2148 2149 name = va_arg(ap, char *); 2150 pai = va_arg(ap, const struct addrinfo *); 2151 2152 memset(&sentinel, 0, sizeof(sentinel)); 2153 cur = &sentinel; 2154 2155 THREAD_LOCK(); 2156 if (!__ypdomain) { 2157 if (_yp_check(&__ypdomain) == 0) { 2158 THREAD_UNLOCK(); 2159 return NS_UNAVAIL; 2160 } 2161 } 2162 if (__ypcurrent) 2163 free(__ypcurrent); 2164 __ypcurrent = NULL; 2165 2166 /* hosts.byname is only for IPv4 (Solaris8) */ 2167 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2168 r = yp_match(__ypdomain, "hosts.byname", name, 2169 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 2170 if (r == 0) { 2171 struct addrinfo ai4; 2172 2173 ai4 = *pai; 2174 ai4.ai_family = AF_INET; 2175 ai = _yphostent(__ypcurrent, &ai4); 2176 if (ai) { 2177 cur->ai_next = ai; 2178 while (cur && cur->ai_next) 2179 cur = cur->ai_next; 2180 } 2181 } 2182 } 2183 2184 /* ipnodes.byname can hold both IPv4/v6 */ 2185 r = yp_match(__ypdomain, "ipnodes.byname", name, 2186 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 2187 if (r == 0) { 2188 ai = _yphostent(__ypcurrent, pai); 2189 if (ai) { 2190 cur->ai_next = ai; 2191 while (cur && cur->ai_next) 2192 cur = cur->ai_next; 2193 } 2194 } 2195 THREAD_UNLOCK(); 2196 2197 if (sentinel.ai_next == NULL) { 2198 h_errno = HOST_NOT_FOUND; 2199 return NS_NOTFOUND; 2200 } 2201 *((struct addrinfo **)rv) = sentinel.ai_next; 2202 return NS_SUCCESS; 2203 } 2204 #endif 2205 2206 /* resolver logic */ 2207 2208 extern const char *__hostalias(const char *); 2209 2210 /* 2211 * Formulate a normal query, send, and await answer. 2212 * Returned answer is placed in supplied buffer "answer". 2213 * Perform preliminary check of answer, returning success only 2214 * if no error is indicated and the answer count is nonzero. 2215 * Return the size of the response on success, -1 on error. 2216 * Error number is left in h_errno. 2217 * 2218 * Caller must parse answer and determine whether it answers the question. 2219 */ 2220 static int 2221 res_queryN(name, target) 2222 const char *name; /* domain name */ 2223 struct res_target *target; 2224 { 2225 u_char *buf; 2226 HEADER *hp; 2227 int n; 2228 struct res_target *t; 2229 int rcode; 2230 int ancount; 2231 2232 rcode = NOERROR; 2233 ancount = 0; 2234 2235 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2236 h_errno = NETDB_INTERNAL; 2237 return (-1); 2238 } 2239 2240 buf = malloc(MAXPACKET); 2241 if (!buf) { 2242 h_errno = NETDB_INTERNAL; 2243 return -1; 2244 } 2245 2246 for (t = target; t; t = t->next) { 2247 int class, type; 2248 u_char *answer; 2249 int anslen; 2250 2251 hp = (HEADER *)(void *)t->answer; 2252 hp->rcode = NOERROR; /* default */ 2253 2254 /* make it easier... */ 2255 class = t->qclass; 2256 type = t->qtype; 2257 answer = t->answer; 2258 anslen = t->anslen; 2259 #ifdef DEBUG 2260 if (_res.options & RES_DEBUG) 2261 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2262 #endif 2263 2264 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, 2265 buf, MAXPACKET); 2266 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) 2267 n = res_opt(n, buf, MAXPACKET, anslen); 2268 if (n <= 0) { 2269 #ifdef DEBUG 2270 if (_res.options & RES_DEBUG) 2271 printf(";; res_query: mkquery failed\n"); 2272 #endif 2273 free(buf); 2274 h_errno = NO_RECOVERY; 2275 return (n); 2276 } 2277 n = res_send(buf, n, answer, anslen); 2278 #if 0 2279 if (n < 0) { 2280 #ifdef DEBUG 2281 if (_res.options & RES_DEBUG) 2282 printf(";; res_query: send error\n"); 2283 #endif 2284 free(buf); 2285 h_errno = TRY_AGAIN; 2286 return (n); 2287 } 2288 #endif 2289 2290 if (n < 0 || n > anslen) 2291 hp->rcode = FORMERR; /* XXX not very informative */ 2292 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2293 rcode = hp->rcode; /* record most recent error */ 2294 #ifdef DEBUG 2295 if (_res.options & RES_DEBUG) 2296 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2297 ntohs(hp->ancount)); 2298 #endif 2299 continue; 2300 } 2301 2302 ancount += ntohs(hp->ancount); 2303 2304 t->n = n; 2305 } 2306 2307 free(buf); 2308 2309 if (ancount == 0) { 2310 switch (rcode) { 2311 case NXDOMAIN: 2312 h_errno = HOST_NOT_FOUND; 2313 break; 2314 case SERVFAIL: 2315 h_errno = TRY_AGAIN; 2316 break; 2317 case NOERROR: 2318 h_errno = NO_DATA; 2319 break; 2320 case FORMERR: 2321 case NOTIMP: 2322 case REFUSED: 2323 default: 2324 h_errno = NO_RECOVERY; 2325 break; 2326 } 2327 return (-1); 2328 } 2329 return (ancount); 2330 } 2331 2332 /* 2333 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2334 * Return the size of the response on success, -1 on error. 2335 * If enabled, implement search rules until answer or unrecoverable failure 2336 * is detected. Error code, if any, is left in h_errno. 2337 */ 2338 static int 2339 res_searchN(name, target) 2340 const char *name; /* domain name */ 2341 struct res_target *target; 2342 { 2343 const char *cp, * const *domain; 2344 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2345 u_int dots; 2346 int trailing_dot, ret, saved_herrno; 2347 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 2348 2349 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2350 h_errno = NETDB_INTERNAL; 2351 return (-1); 2352 } 2353 2354 errno = 0; 2355 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 2356 dots = 0; 2357 for (cp = name; *cp; cp++) 2358 dots += (*cp == '.'); 2359 trailing_dot = 0; 2360 if (cp > name && *--cp == '.') 2361 trailing_dot++; 2362 2363 /* 2364 * if there aren't any dots, it could be a user-level alias 2365 */ 2366 if (!dots && (cp = __hostalias(name)) != NULL) 2367 return (res_queryN(cp, target)); 2368 2369 /* 2370 * If there are dots in the name already, let's just give it a try 2371 * 'as is'. The threshold can be set with the "ndots" option. 2372 */ 2373 saved_herrno = -1; 2374 if (dots >= _res.ndots) { 2375 ret = res_querydomainN(name, NULL, target); 2376 if (ret > 0) 2377 return (ret); 2378 saved_herrno = h_errno; 2379 tried_as_is++; 2380 } 2381 2382 /* 2383 * We do at least one level of search if 2384 * - there is no dot and RES_DEFNAME is set, or 2385 * - there is at least one dot, there is no trailing dot, 2386 * and RES_DNSRCH is set. 2387 */ 2388 if ((!dots && (_res.options & RES_DEFNAMES)) || 2389 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { 2390 int done = 0; 2391 2392 for (domain = (const char * const *)_res.dnsrch; 2393 *domain && !done; 2394 domain++) { 2395 2396 ret = res_querydomainN(name, *domain, target); 2397 if (ret > 0) 2398 return (ret); 2399 2400 /* 2401 * If no server present, give up. 2402 * If name isn't found in this domain, 2403 * keep trying higher domains in the search list 2404 * (if that's enabled). 2405 * On a NO_DATA error, keep trying, otherwise 2406 * a wildcard entry of another type could keep us 2407 * from finding this entry higher in the domain. 2408 * If we get some other error (negative answer or 2409 * server failure), then stop searching up, 2410 * but try the input name below in case it's 2411 * fully-qualified. 2412 */ 2413 if (errno == ECONNREFUSED) { 2414 h_errno = TRY_AGAIN; 2415 return (-1); 2416 } 2417 2418 switch (h_errno) { 2419 case NO_DATA: 2420 got_nodata++; 2421 /* FALLTHROUGH */ 2422 case HOST_NOT_FOUND: 2423 /* keep trying */ 2424 break; 2425 case TRY_AGAIN: 2426 if (hp->rcode == SERVFAIL) { 2427 /* try next search element, if any */ 2428 got_servfail++; 2429 break; 2430 } 2431 /* FALLTHROUGH */ 2432 default: 2433 /* anything else implies that we're done */ 2434 done++; 2435 } 2436 /* 2437 * if we got here for some reason other than DNSRCH, 2438 * we only wanted one iteration of the loop, so stop. 2439 */ 2440 if (!(_res.options & RES_DNSRCH)) 2441 done++; 2442 } 2443 } 2444 2445 /* 2446 * if we have not already tried the name "as is", do that now. 2447 * note that we do this regardless of how many dots were in the 2448 * name or whether it ends with a dot. 2449 */ 2450 if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) { 2451 ret = res_querydomainN(name, NULL, target); 2452 if (ret > 0) 2453 return (ret); 2454 } 2455 2456 /* 2457 * if we got here, we didn't satisfy the search. 2458 * if we did an initial full query, return that query's h_errno 2459 * (note that we wouldn't be here if that query had succeeded). 2460 * else if we ever got a nodata, send that back as the reason. 2461 * else send back meaningless h_errno, that being the one from 2462 * the last DNSRCH we did. 2463 */ 2464 if (saved_herrno != -1) 2465 h_errno = saved_herrno; 2466 else if (got_nodata) 2467 h_errno = NO_DATA; 2468 else if (got_servfail) 2469 h_errno = TRY_AGAIN; 2470 return (-1); 2471 } 2472 2473 /* 2474 * Perform a call on res_query on the concatenation of name and domain, 2475 * removing a trailing dot from name if domain is NULL. 2476 */ 2477 static int 2478 res_querydomainN(name, domain, target) 2479 const char *name, *domain; 2480 struct res_target *target; 2481 { 2482 char nbuf[MAXDNAME]; 2483 const char *longname = nbuf; 2484 size_t n, d; 2485 2486 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2487 h_errno = NETDB_INTERNAL; 2488 return (-1); 2489 } 2490 #ifdef DEBUG 2491 if (_res.options & RES_DEBUG) 2492 printf(";; res_querydomain(%s, %s)\n", 2493 name, domain?domain:"<Nil>"); 2494 #endif 2495 if (domain == NULL) { 2496 /* 2497 * Check for trailing '.'; 2498 * copy without '.' if present. 2499 */ 2500 n = strlen(name); 2501 if (n >= MAXDNAME) { 2502 h_errno = NO_RECOVERY; 2503 return (-1); 2504 } 2505 if (n > 0 && name[--n] == '.') { 2506 strncpy(nbuf, name, n); 2507 nbuf[n] = '\0'; 2508 } else 2509 longname = name; 2510 } else { 2511 n = strlen(name); 2512 d = strlen(domain); 2513 if (n + d + 1 >= MAXDNAME) { 2514 h_errno = NO_RECOVERY; 2515 return (-1); 2516 } 2517 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2518 } 2519 return (res_queryN(longname, target)); 2520 } 2521