getaddrinfo.c revision 140906
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: head/lib/libc/net/getaddrinfo.c 140906 2005-01-27 14:41:56Z ume $"); 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 <sys/ioctl.h> 79#include <netinet6/in6_var.h> /* XXX */ 80#endif 81#include <arpa/inet.h> 82#include <arpa/nameser.h> 83#include <rpc/rpc.h> 84#include <rpcsvc/yp_prot.h> 85#include <rpcsvc/ypclnt.h> 86#include <netdb.h> 87#include <pthread.h> 88#include <resolv.h> 89#include <string.h> 90#include <stdlib.h> 91#include <stddef.h> 92#include <ctype.h> 93#include <unistd.h> 94#include <stdio.h> 95#include <errno.h> 96 97#include "res_config.h" 98 99#ifdef DEBUG 100#include <syslog.h> 101#endif 102 103#include <stdarg.h> 104#include <nsswitch.h> 105#include "un-namespace.h" 106#include "libc_private.h" 107 108#if defined(__KAME__) && defined(INET6) 109# define FAITH 110#endif 111 112#define SUCCESS 0 113#define ANY 0 114#define YES 1 115#define NO 0 116 117static const char in_addrany[] = { 0, 0, 0, 0 }; 118static const char in_loopback[] = { 127, 0, 0, 1 }; 119#ifdef INET6 120static const char in6_addrany[] = { 121 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 122}; 123static const char in6_loopback[] = { 124 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 125}; 126#endif 127 128struct policyqueue { 129 TAILQ_ENTRY(policyqueue) pc_entry; 130#ifdef INET6 131 struct in6_addrpolicy pc_policy; 132#endif 133}; 134TAILQ_HEAD(policyhead, policyqueue); 135 136static const struct afd { 137 int a_af; 138 int a_addrlen; 139 int a_socklen; 140 int a_off; 141 const char *a_addrany; 142 const char *a_loopback; 143 int a_scoped; 144} afdl [] = { 145#ifdef INET6 146#define N_INET6 0 147 {PF_INET6, sizeof(struct in6_addr), 148 sizeof(struct sockaddr_in6), 149 offsetof(struct sockaddr_in6, sin6_addr), 150 in6_addrany, in6_loopback, 1}, 151#define N_INET 1 152#else 153#define N_INET 0 154#endif 155 {PF_INET, sizeof(struct in_addr), 156 sizeof(struct sockaddr_in), 157 offsetof(struct sockaddr_in, sin_addr), 158 in_addrany, in_loopback, 0}, 159 {0, 0, 0, 0, NULL, NULL, 0}, 160}; 161 162struct explore { 163 int e_af; 164 int e_socktype; 165 int e_protocol; 166 const char *e_protostr; 167 int e_wild; 168#define WILD_AF(ex) ((ex)->e_wild & 0x01) 169#define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 170#define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 171}; 172 173static const struct explore explore[] = { 174#if 0 175 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 176#endif 177#ifdef INET6 178 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 179 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 180 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 181#endif 182 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 183 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 184 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 185 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 186 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 187 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, 188 { -1, 0, 0, NULL, 0 }, 189}; 190 191#ifdef INET6 192#define PTON_MAX 16 193#else 194#define PTON_MAX 4 195#endif 196 197#define AIO_SRCFLAG_DEPRECATED 0x1 198 199struct ai_order { 200 union { 201 struct sockaddr_storage aiou_ss; 202 struct sockaddr aiou_sa; 203 } aio_src_un; 204#define aio_srcsa aio_src_un.aiou_sa 205 u_int32_t aio_srcflag; 206 int aio_srcscope; 207 int aio_dstscope; 208 struct policyqueue *aio_srcpolicy; 209 struct policyqueue *aio_dstpolicy; 210 struct addrinfo *aio_ai; 211 int aio_matchlen; 212}; 213 214static const ns_src default_dns_files[] = { 215 { NSSRC_FILES, NS_SUCCESS }, 216 { NSSRC_DNS, NS_SUCCESS }, 217 { 0 } 218}; 219 220struct res_target { 221 struct res_target *next; 222 const char *name; /* domain name */ 223 int qclass, qtype; /* class and type of query */ 224 u_char *answer; /* buffer to put answer */ 225 int anslen; /* size of answer buffer */ 226 int n; /* result length */ 227}; 228 229#define MAXPACKET (64*1024) 230 231typedef union { 232 HEADER hdr; 233 u_char buf[MAXPACKET]; 234} querybuf; 235 236static int str_isnumber(const char *); 237static int explore_null(const struct addrinfo *, 238 const char *, struct addrinfo **); 239static int explore_numeric(const struct addrinfo *, const char *, 240 const char *, struct addrinfo **, const char *); 241static int explore_numeric_scope(const struct addrinfo *, const char *, 242 const char *, struct addrinfo **); 243static int get_canonname(const struct addrinfo *, 244 struct addrinfo *, const char *); 245static struct addrinfo *get_ai(const struct addrinfo *, 246 const struct afd *, const char *); 247static int get_portmatch(const struct addrinfo *, const char *); 248static int get_port(struct addrinfo *, const char *, int); 249static const struct afd *find_afd(int); 250static int addrconfig(struct addrinfo *); 251static void set_source(struct ai_order *, struct policyhead *); 252static int comp_dst(const void *, const void *); 253#ifdef INET6 254static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 255#endif 256static int gai_addr2scopetype(struct sockaddr *); 257 258static int explore_fqdn(const struct addrinfo *, const char *, 259 const char *, struct addrinfo **); 260 261static int reorder(struct addrinfo *); 262static int get_addrselectpolicy(struct policyhead *); 263static void free_addrselectpolicy(struct policyhead *); 264static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 265 struct policyhead *); 266static int matchlen(struct sockaddr *, struct sockaddr *); 267 268static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 269 const struct addrinfo *); 270#if defined(RESOLVSORT) 271static int addr4sort(struct addrinfo *); 272#endif 273static int _dns_getaddrinfo(void *, void *, va_list); 274static void _sethtent(void); 275static void _endhtent(void); 276static struct addrinfo *_gethtent(const char *, const struct addrinfo *); 277static int _files_getaddrinfo(void *, void *, va_list); 278#ifdef YP 279static struct addrinfo *_yphostent(char *, const struct addrinfo *); 280static int _yp_getaddrinfo(void *, void *, va_list); 281#endif 282 283static int res_queryN(const char *, struct res_target *); 284static int res_searchN(const char *, struct res_target *); 285static int res_querydomainN(const char *, const char *, 286 struct res_target *); 287 288static struct ai_errlist { 289 const char *str; 290 int code; 291} ai_errlist[] = { 292 { "Success", 0, }, 293 { "Temporary failure in name resolution", EAI_AGAIN, }, 294 { "Invalid value for ai_flags", EAI_BADFLAGS, }, 295 { "Non-recoverable failure in name resolution", EAI_FAIL, }, 296 { "ai_family not supported", EAI_FAMILY, }, 297 { "Memory allocation failure", EAI_MEMORY, }, 298 { "hostname nor servname provided, or not known", EAI_NONAME, }, 299 { "servname not supported for ai_socktype", EAI_SERVICE, }, 300 { "ai_socktype not supported", EAI_SOCKTYPE, }, 301 { "System error returned in errno", EAI_SYSTEM, }, 302 { "Invalid value for hints", EAI_BADHINTS, }, 303 { "Resolved protocol is unknown", EAI_PROTOCOL, }, 304 /* backward compatibility with userland code prior to 2553bis-02 */ 305 { "Address family for hostname not supported", 1, }, 306 { "No address associated with hostname", 7, }, 307 { NULL, -1, }, 308}; 309 310/* 311 * XXX: Many dependencies are not thread-safe. So, we share lock between 312 * getaddrinfo() and getipnodeby*(). Still, we cannot use 313 * getaddrinfo() and getipnodeby*() in conjunction with other 314 * functions which call them. 315 */ 316pthread_mutex_t __getaddrinfo_thread_lock = PTHREAD_MUTEX_INITIALIZER; 317#define THREAD_LOCK() \ 318 if (__isthreaded) _pthread_mutex_lock(&__getaddrinfo_thread_lock); 319#define THREAD_UNLOCK() \ 320 if (__isthreaded) _pthread_mutex_unlock(&__getaddrinfo_thread_lock); 321 322/* XXX macros that make external reference is BAD. */ 323 324#define GET_AI(ai, afd, addr) \ 325do { \ 326 /* external reference: pai, error, and label free */ \ 327 (ai) = get_ai(pai, (afd), (addr)); \ 328 if ((ai) == NULL) { \ 329 error = EAI_MEMORY; \ 330 goto free; \ 331 } \ 332} while (/*CONSTCOND*/0) 333 334#define GET_PORT(ai, serv) \ 335do { \ 336 /* external reference: error and label free */ \ 337 error = get_port((ai), (serv), 0); \ 338 if (error != 0) \ 339 goto free; \ 340} while (/*CONSTCOND*/0) 341 342#define GET_CANONNAME(ai, str) \ 343do { \ 344 /* external reference: pai, error and label free */ \ 345 error = get_canonname(pai, (ai), (str)); \ 346 if (error != 0) \ 347 goto free; \ 348} while (/*CONSTCOND*/0) 349 350#define ERR(err) \ 351do { \ 352 /* external reference: error, and label bad */ \ 353 error = (err); \ 354 goto bad; \ 355 /*NOTREACHED*/ \ 356} while (/*CONSTCOND*/0) 357 358#define MATCH_FAMILY(x, y, w) \ 359 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 360#define MATCH(x, y, w) \ 361 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 362 363char * 364gai_strerror(ecode) 365 int ecode; 366{ 367 struct ai_errlist *p; 368 369 for (p = ai_errlist; p->str; p++) { 370 if (p->code == ecode) 371 return (char *)p->str; 372 } 373 return "Unknown error"; 374} 375 376void 377freeaddrinfo(ai) 378 struct addrinfo *ai; 379{ 380 struct addrinfo *next; 381 382 do { 383 next = ai->ai_next; 384 if (ai->ai_canonname) 385 free(ai->ai_canonname); 386 /* no need to free(ai->ai_addr) */ 387 free(ai); 388 ai = next; 389 } while (ai); 390} 391 392static int 393str_isnumber(p) 394 const char *p; 395{ 396 char *ep; 397 398 if (*p == '\0') 399 return NO; 400 ep = NULL; 401 errno = 0; 402 (void)strtoul(p, &ep, 10); 403 if (errno == 0 && ep && *ep == '\0') 404 return YES; 405 else 406 return NO; 407} 408 409int 410getaddrinfo(hostname, servname, hints, res) 411 const char *hostname, *servname; 412 const struct addrinfo *hints; 413 struct addrinfo **res; 414{ 415 struct addrinfo sentinel; 416 struct addrinfo *cur; 417 int error = 0; 418 struct addrinfo ai; 419 struct addrinfo ai0; 420 struct addrinfo *pai; 421 const struct explore *ex; 422 int numeric = 0; 423 424 memset(&sentinel, 0, sizeof(sentinel)); 425 cur = &sentinel; 426 pai = &ai; 427 pai->ai_flags = 0; 428 pai->ai_family = PF_UNSPEC; 429 pai->ai_socktype = ANY; 430 pai->ai_protocol = ANY; 431 pai->ai_addrlen = 0; 432 pai->ai_canonname = NULL; 433 pai->ai_addr = NULL; 434 pai->ai_next = NULL; 435 436 if (hostname == NULL && servname == NULL) 437 return EAI_NONAME; 438 if (hints) { 439 /* error check for hints */ 440 if (hints->ai_addrlen || hints->ai_canonname || 441 hints->ai_addr || hints->ai_next) 442 ERR(EAI_BADHINTS); /* xxx */ 443 if (hints->ai_flags & ~AI_MASK) 444 ERR(EAI_BADFLAGS); 445 switch (hints->ai_family) { 446 case PF_UNSPEC: 447 case PF_INET: 448#ifdef INET6 449 case PF_INET6: 450#endif 451 break; 452 default: 453 ERR(EAI_FAMILY); 454 } 455 memcpy(pai, hints, sizeof(*pai)); 456 457 /* 458 * if both socktype/protocol are specified, check if they 459 * are meaningful combination. 460 */ 461 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 462 for (ex = explore; ex->e_af >= 0; ex++) { 463 if (pai->ai_family != ex->e_af) 464 continue; 465 if (ex->e_socktype == ANY) 466 continue; 467 if (ex->e_protocol == ANY) 468 continue; 469 if (pai->ai_socktype == ex->e_socktype && 470 pai->ai_protocol != ex->e_protocol) { 471 ERR(EAI_BADHINTS); 472 } 473 } 474 } 475 } 476 477 /* 478 * post-2553: AI_ALL and AI_V4MAPPED are effective only against 479 * AF_INET6 query. They need to be ignored if specified in other 480 * occassions. 481 */ 482 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 483 case AI_V4MAPPED: 484 case AI_ALL | AI_V4MAPPED: 485 if (pai->ai_family != AF_INET6) 486 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 487 break; 488 case AI_ALL: 489#if 1 490 /* illegal */ 491 ERR(EAI_BADFLAGS); 492#else 493 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 494#endif 495 break; 496 } 497 498 /* 499 * check for special cases. (1) numeric servname is disallowed if 500 * socktype/protocol are left unspecified. (2) servname is disallowed 501 * for raw and other inet{,6} sockets. 502 */ 503 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 504#ifdef PF_INET6 505 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 506#endif 507 ) { 508 ai0 = *pai; /* backup *pai */ 509 510 if (pai->ai_family == PF_UNSPEC) { 511#ifdef PF_INET6 512 pai->ai_family = PF_INET6; 513#else 514 pai->ai_family = PF_INET; 515#endif 516 } 517 error = get_portmatch(pai, servname); 518 if (error) 519 ERR(error); 520 521 *pai = ai0; 522 } 523 524 ai0 = *pai; 525 526 /* NULL hostname, or numeric hostname */ 527 for (ex = explore; ex->e_af >= 0; ex++) { 528 *pai = ai0; 529 530 /* PF_UNSPEC entries are prepared for DNS queries only */ 531 if (ex->e_af == PF_UNSPEC) 532 continue; 533 534 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 535 continue; 536 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 537 continue; 538 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 539 continue; 540 541 if (pai->ai_family == PF_UNSPEC) 542 pai->ai_family = ex->e_af; 543 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 544 pai->ai_socktype = ex->e_socktype; 545 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 546 pai->ai_protocol = ex->e_protocol; 547 548 if (hostname == NULL) 549 error = explore_null(pai, servname, &cur->ai_next); 550 else 551 error = explore_numeric_scope(pai, hostname, servname, 552 &cur->ai_next); 553 554 if (error) 555 goto free; 556 557 while (cur && cur->ai_next) 558 cur = cur->ai_next; 559 } 560 561 /* 562 * XXX 563 * If numreic representation of AF1 can be interpreted as FQDN 564 * representation of AF2, we need to think again about the code below. 565 */ 566 if (sentinel.ai_next) { 567 numeric = 1; 568 goto good; 569 } 570 571 if (hostname == NULL) 572 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 573 if (pai->ai_flags & AI_NUMERICHOST) 574 ERR(EAI_NONAME); 575 576 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 577 ERR(EAI_FAIL); 578 579 /* 580 * hostname as alphabetical name. 581 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 582 * outer loop by AFs. 583 */ 584 for (ex = explore; ex->e_af >= 0; ex++) { 585 *pai = ai0; 586 587 /* require exact match for family field */ 588 if (pai->ai_family != ex->e_af) 589 continue; 590 591 if (!MATCH(pai->ai_socktype, ex->e_socktype, 592 WILD_SOCKTYPE(ex))) { 593 continue; 594 } 595 if (!MATCH(pai->ai_protocol, ex->e_protocol, 596 WILD_PROTOCOL(ex))) { 597 continue; 598 } 599 600 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 601 pai->ai_socktype = ex->e_socktype; 602 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 603 pai->ai_protocol = ex->e_protocol; 604 605 error = explore_fqdn(pai, hostname, servname, 606 &cur->ai_next); 607 608 while (cur && cur->ai_next) 609 cur = cur->ai_next; 610 } 611 612 /* XXX inhibit errors if we have the result */ 613 if (sentinel.ai_next) 614 error = 0; 615 616good: 617 /* 618 * ensure we return either: 619 * - error == 0, non-NULL *res 620 * - error != 0, NULL *res 621 */ 622 if (error == 0) { 623 if (sentinel.ai_next) { 624 /* 625 * If the returned entry is for an active connection, 626 * and the given name is not numeric, reorder the 627 * list, so that the application would try the list 628 * in the most efficient order. 629 */ 630 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 631 if (!numeric) 632 (void)reorder(&sentinel); 633 } 634 *res = sentinel.ai_next; 635 return SUCCESS; 636 } else 637 error = EAI_FAIL; 638 } 639free: 640bad: 641 if (sentinel.ai_next) 642 freeaddrinfo(sentinel.ai_next); 643 *res = NULL; 644 return error; 645} 646 647static int 648reorder(sentinel) 649 struct addrinfo *sentinel; 650{ 651 struct addrinfo *ai, **aip; 652 struct ai_order *aio; 653 int i, n; 654 struct policyhead policyhead; 655 656 /* count the number of addrinfo elements for sorting. */ 657 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 658 ; 659 660 /* 661 * If the number is small enough, we can skip the reordering process. 662 */ 663 if (n <= 1) 664 return(n); 665 666 /* allocate a temporary array for sort and initialization of it. */ 667 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 668 return(n); /* give up reordering */ 669 memset(aio, 0, sizeof(*aio) * n); 670 671 /* retrieve address selection policy from the kernel */ 672 TAILQ_INIT(&policyhead); 673 if (!get_addrselectpolicy(&policyhead)) { 674 /* no policy is installed into kernel, we don't sort. */ 675 free(aio); 676 return (n); 677 } 678 679 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 680 aio[i].aio_ai = ai; 681 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 682 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 683 &policyhead); 684 set_source(&aio[i], &policyhead); 685 } 686 687 /* perform sorting. */ 688 qsort(aio, n, sizeof(*aio), comp_dst); 689 690 /* reorder the addrinfo chain. */ 691 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 692 *aip = aio[i].aio_ai; 693 aip = &aio[i].aio_ai->ai_next; 694 } 695 *aip = NULL; 696 697 /* cleanup and return */ 698 free(aio); 699 free_addrselectpolicy(&policyhead); 700 return(n); 701} 702 703static int 704get_addrselectpolicy(head) 705 struct policyhead *head; 706{ 707#ifdef INET6 708 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 709 size_t l; 710 char *buf; 711 struct in6_addrpolicy *pol, *ep; 712 713 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 714 return (0); 715 if ((buf = malloc(l)) == NULL) 716 return (0); 717 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 718 free(buf); 719 return (0); 720 } 721 722 ep = (struct in6_addrpolicy *)(buf + l); 723 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 724 struct policyqueue *new; 725 726 if ((new = malloc(sizeof(*new))) == NULL) { 727 free_addrselectpolicy(head); /* make the list empty */ 728 break; 729 } 730 new->pc_policy = *pol; 731 TAILQ_INSERT_TAIL(head, new, pc_entry); 732 } 733 734 free(buf); 735 return (1); 736#else 737 return (0); 738#endif 739} 740 741static void 742free_addrselectpolicy(head) 743 struct policyhead *head; 744{ 745 struct policyqueue *ent, *nent; 746 747 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 748 nent = TAILQ_NEXT(ent, pc_entry); 749 TAILQ_REMOVE(head, ent, pc_entry); 750 free(ent); 751 } 752} 753 754static struct policyqueue * 755match_addrselectpolicy(addr, head) 756 struct sockaddr *addr; 757 struct policyhead *head; 758{ 759#ifdef INET6 760 struct policyqueue *ent, *bestent = NULL; 761 struct in6_addrpolicy *pol; 762 int matchlen, bestmatchlen = -1; 763 u_char *mp, *ep, *k, *p, m; 764 struct sockaddr_in6 key; 765 766 switch(addr->sa_family) { 767 case AF_INET6: 768 key = *(struct sockaddr_in6 *)addr; 769 break; 770 case AF_INET: 771 /* convert the address into IPv4-mapped IPv6 address. */ 772 memset(&key, 0, sizeof(key)); 773 key.sin6_family = AF_INET6; 774 key.sin6_len = sizeof(key); 775 key.sin6_addr.s6_addr[10] = 0xff; 776 key.sin6_addr.s6_addr[11] = 0xff; 777 memcpy(&key.sin6_addr.s6_addr[12], 778 &((struct sockaddr_in *)addr)->sin_addr, 4); 779 break; 780 default: 781 return(NULL); 782 } 783 784 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 785 pol = &ent->pc_policy; 786 matchlen = 0; 787 788 mp = (u_char *)&pol->addrmask.sin6_addr; 789 ep = mp + 16; /* XXX: scope field? */ 790 k = (u_char *)&key.sin6_addr; 791 p = (u_char *)&pol->addr.sin6_addr; 792 for (; mp < ep && *mp; mp++, k++, p++) { 793 m = *mp; 794 if ((*k & m) != *p) 795 goto next; /* not match */ 796 if (m == 0xff) /* short cut for a typical case */ 797 matchlen += 8; 798 else { 799 while (m >= 0x80) { 800 matchlen++; 801 m <<= 1; 802 } 803 } 804 } 805 806 /* matched. check if this is better than the current best. */ 807 if (matchlen > bestmatchlen) { 808 bestent = ent; 809 bestmatchlen = matchlen; 810 } 811 812 next: 813 continue; 814 } 815 816 return(bestent); 817#else 818 return(NULL); 819#endif 820 821} 822 823static void 824set_source(aio, ph) 825 struct ai_order *aio; 826 struct policyhead *ph; 827{ 828 struct addrinfo ai = *aio->aio_ai; 829 struct sockaddr_storage ss; 830 int s, srclen; 831 832 /* set unspec ("no source is available"), just in case */ 833 aio->aio_srcsa.sa_family = AF_UNSPEC; 834 aio->aio_srcscope = -1; 835 836 switch(ai.ai_family) { 837 case AF_INET: 838#ifdef INET6 839 case AF_INET6: 840#endif 841 break; 842 default: /* ignore unsupported AFs explicitly */ 843 return; 844 } 845 846 /* XXX: make a dummy addrinfo to call connect() */ 847 ai.ai_socktype = SOCK_DGRAM; 848 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 849 ai.ai_next = NULL; 850 memset(&ss, 0, sizeof(ss)); 851 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 852 ai.ai_addr = (struct sockaddr *)&ss; 853 get_port(&ai, "1", 0); 854 855 /* open a socket to get the source address for the given dst */ 856 if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0) 857 return; /* give up */ 858 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 859 goto cleanup; 860 srclen = ai.ai_addrlen; 861 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 862 aio->aio_srcsa.sa_family = AF_UNSPEC; 863 goto cleanup; 864 } 865 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 866 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 867 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 868#ifdef INET6 869 if (ai.ai_family == AF_INET6) { 870 struct in6_ifreq ifr6; 871 u_int32_t flags6; 872 873 /* XXX: interface name should not be hardcoded */ 874 strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name)); 875 memset(&ifr6, 0, sizeof(ifr6)); 876 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 877 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 878 flags6 = ifr6.ifr_ifru.ifru_flags6; 879 if ((flags6 & IN6_IFF_DEPRECATED)) 880 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 881 } 882 } 883#endif 884 885 cleanup: 886 _close(s); 887 return; 888} 889 890static int 891matchlen(src, dst) 892 struct sockaddr *src, *dst; 893{ 894 int match = 0; 895 u_char *s, *d; 896 u_char *lim, r; 897 int addrlen; 898 899 switch (src->sa_family) { 900#ifdef INET6 901 case AF_INET6: 902 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 903 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 904 addrlen = sizeof(struct in6_addr); 905 lim = s + addrlen; 906 break; 907#endif 908 case AF_INET: 909 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 910 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 911 addrlen = sizeof(struct in_addr); 912 lim = s + addrlen; 913 break; 914 default: 915 return(0); 916 } 917 918 while (s < lim) 919 if ((r = (*d++ ^ *s++)) != 0) { 920 while (r < addrlen * 8) { 921 match++; 922 r <<= 1; 923 } 924 break; 925 } else 926 match += 8; 927 return(match); 928} 929 930static int 931comp_dst(arg1, arg2) 932 const void *arg1, *arg2; 933{ 934 const struct ai_order *dst1 = arg1, *dst2 = arg2; 935 936 /* 937 * Rule 1: Avoid unusable destinations. 938 * XXX: we currently do not consider if an appropriate route exists. 939 */ 940 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 941 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 942 return(-1); 943 } 944 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 945 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 946 return(1); 947 } 948 949 /* Rule 2: Prefer matching scope. */ 950 if (dst1->aio_dstscope == dst1->aio_srcscope && 951 dst2->aio_dstscope != dst2->aio_srcscope) { 952 return(-1); 953 } 954 if (dst1->aio_dstscope != dst1->aio_srcscope && 955 dst2->aio_dstscope == dst2->aio_srcscope) { 956 return(1); 957 } 958 959 /* Rule 3: Avoid deprecated addresses. */ 960 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 961 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 962 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 963 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 964 return(-1); 965 } 966 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 967 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 968 return(1); 969 } 970 } 971 972 /* Rule 4: Prefer home addresses. */ 973 /* XXX: not implemented yet */ 974 975 /* Rule 5: Prefer matching label. */ 976#ifdef INET6 977 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 978 dst1->aio_srcpolicy->pc_policy.label == 979 dst1->aio_dstpolicy->pc_policy.label && 980 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 981 dst2->aio_srcpolicy->pc_policy.label != 982 dst2->aio_dstpolicy->pc_policy.label)) { 983 return(-1); 984 } 985 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 986 dst2->aio_srcpolicy->pc_policy.label == 987 dst2->aio_dstpolicy->pc_policy.label && 988 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 989 dst1->aio_srcpolicy->pc_policy.label != 990 dst1->aio_dstpolicy->pc_policy.label)) { 991 return(1); 992 } 993#endif 994 995 /* Rule 6: Prefer higher precedence. */ 996#ifdef INET6 997 if (dst1->aio_dstpolicy && 998 (dst2->aio_dstpolicy == NULL || 999 dst1->aio_dstpolicy->pc_policy.preced > 1000 dst2->aio_dstpolicy->pc_policy.preced)) { 1001 return(-1); 1002 } 1003 if (dst2->aio_dstpolicy && 1004 (dst1->aio_dstpolicy == NULL || 1005 dst2->aio_dstpolicy->pc_policy.preced > 1006 dst1->aio_dstpolicy->pc_policy.preced)) { 1007 return(1); 1008 } 1009#endif 1010 1011 /* Rule 7: Prefer native transport. */ 1012 /* XXX: not implemented yet */ 1013 1014 /* Rule 8: Prefer smaller scope. */ 1015 if (dst1->aio_dstscope >= 0 && 1016 dst1->aio_dstscope < dst2->aio_dstscope) { 1017 return(-1); 1018 } 1019 if (dst2->aio_dstscope >= 0 && 1020 dst2->aio_dstscope < dst1->aio_dstscope) { 1021 return(1); 1022 } 1023 1024 /* 1025 * Rule 9: Use longest matching prefix. 1026 * We compare the match length in a same AF only. 1027 */ 1028 if (dst1->aio_ai->ai_addr->sa_family == 1029 dst2->aio_ai->ai_addr->sa_family) { 1030 if (dst1->aio_matchlen > dst2->aio_matchlen) { 1031 return(-1); 1032 } 1033 if (dst1->aio_matchlen < dst2->aio_matchlen) { 1034 return(1); 1035 } 1036 } 1037 1038 /* Rule 10: Otherwise, leave the order unchanged. */ 1039 return(-1); 1040} 1041 1042/* 1043 * Copy from scope.c. 1044 * XXX: we should standardize the functions and link them as standard 1045 * library. 1046 */ 1047static int 1048gai_addr2scopetype(sa) 1049 struct sockaddr *sa; 1050{ 1051#ifdef INET6 1052 struct sockaddr_in6 *sa6; 1053#endif 1054 struct sockaddr_in *sa4; 1055 1056 switch(sa->sa_family) { 1057#ifdef INET6 1058 case AF_INET6: 1059 sa6 = (struct sockaddr_in6 *)sa; 1060 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1061 /* just use the scope field of the multicast address */ 1062 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1063 } 1064 /* 1065 * Unicast addresses: map scope type to corresponding scope 1066 * value defined for multcast addresses. 1067 * XXX: hardcoded scope type values are bad... 1068 */ 1069 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1070 return(1); /* node local scope */ 1071 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1072 return(2); /* link-local scope */ 1073 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1074 return(5); /* site-local scope */ 1075 return(14); /* global scope */ 1076 break; 1077#endif 1078 case AF_INET: 1079 /* 1080 * IPv4 pseudo scoping according to RFC 3484. 1081 */ 1082 sa4 = (struct sockaddr_in *)sa; 1083 /* IPv4 autoconfiguration addresses have link-local scope. */ 1084 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1085 ((u_char *)&sa4->sin_addr)[1] == 254) 1086 return(2); 1087 /* Private addresses have site-local scope. */ 1088 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1089 (((u_char *)&sa4->sin_addr)[0] == 172 && 1090 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1091 (((u_char *)&sa4->sin_addr)[0] == 192 && 1092 ((u_char *)&sa4->sin_addr)[1] == 168)) 1093 return(14); /* XXX: It should be 5 unless NAT */ 1094 /* Loopback addresses have link-local scope. */ 1095 if (((u_char *)&sa4->sin_addr)[0] == 127) 1096 return(2); 1097 return(14); 1098 break; 1099 default: 1100 errno = EAFNOSUPPORT; /* is this a good error? */ 1101 return(-1); 1102 } 1103} 1104 1105/* 1106 * hostname == NULL. 1107 * passive socket -> anyaddr (0.0.0.0 or ::) 1108 * non-passive socket -> localhost (127.0.0.1 or ::1) 1109 */ 1110static int 1111explore_null(pai, servname, res) 1112 const struct addrinfo *pai; 1113 const char *servname; 1114 struct addrinfo **res; 1115{ 1116 int s; 1117 const struct afd *afd; 1118 struct addrinfo *cur; 1119 struct addrinfo sentinel; 1120 int error; 1121 1122 *res = NULL; 1123 sentinel.ai_next = NULL; 1124 cur = &sentinel; 1125 1126 /* 1127 * filter out AFs that are not supported by the kernel 1128 * XXX errno? 1129 */ 1130 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1131 if (s < 0) { 1132 if (errno != EMFILE) 1133 return 0; 1134 } else 1135 _close(s); 1136 1137 /* 1138 * if the servname does not match socktype/protocol, ignore it. 1139 */ 1140 if (get_portmatch(pai, servname) != 0) 1141 return 0; 1142 1143 afd = find_afd(pai->ai_family); 1144 if (afd == NULL) 1145 return 0; 1146 1147 if (pai->ai_flags & AI_PASSIVE) { 1148 GET_AI(cur->ai_next, afd, afd->a_addrany); 1149 /* xxx meaningless? 1150 * GET_CANONNAME(cur->ai_next, "anyaddr"); 1151 */ 1152 GET_PORT(cur->ai_next, servname); 1153 } else { 1154 GET_AI(cur->ai_next, afd, afd->a_loopback); 1155 /* xxx meaningless? 1156 * GET_CANONNAME(cur->ai_next, "localhost"); 1157 */ 1158 GET_PORT(cur->ai_next, servname); 1159 } 1160 cur = cur->ai_next; 1161 1162 *res = sentinel.ai_next; 1163 return 0; 1164 1165free: 1166 if (sentinel.ai_next) 1167 freeaddrinfo(sentinel.ai_next); 1168 return error; 1169} 1170 1171/* 1172 * numeric hostname 1173 */ 1174static int 1175explore_numeric(pai, hostname, servname, res, canonname) 1176 const struct addrinfo *pai; 1177 const char *hostname; 1178 const char *servname; 1179 struct addrinfo **res; 1180 const char *canonname; 1181{ 1182 const struct afd *afd; 1183 struct addrinfo *cur; 1184 struct addrinfo sentinel; 1185 int error; 1186 char pton[PTON_MAX]; 1187 1188 *res = NULL; 1189 sentinel.ai_next = NULL; 1190 cur = &sentinel; 1191 1192 /* 1193 * if the servname does not match socktype/protocol, ignore it. 1194 */ 1195 if (get_portmatch(pai, servname) != 0) 1196 return 0; 1197 1198 afd = find_afd(pai->ai_family); 1199 if (afd == NULL) 1200 return 0; 1201 1202 switch (afd->a_af) { 1203#if 1 /*X/Open spec*/ 1204 case AF_INET: 1205 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 1206 if (pai->ai_family == afd->a_af || 1207 pai->ai_family == PF_UNSPEC /*?*/) { 1208 GET_AI(cur->ai_next, afd, pton); 1209 GET_PORT(cur->ai_next, servname); 1210 if ((pai->ai_flags & AI_CANONNAME)) { 1211 /* 1212 * Set the numeric address itself as 1213 * the canonical name, based on a 1214 * clarification in rfc3493. 1215 */ 1216 GET_CANONNAME(cur->ai_next, canonname); 1217 } 1218 while (cur && cur->ai_next) 1219 cur = cur->ai_next; 1220 } else 1221 ERR(EAI_FAMILY); /*xxx*/ 1222 } 1223 break; 1224#endif 1225 default: 1226 if (inet_pton(afd->a_af, hostname, pton) == 1) { 1227 if (pai->ai_family == afd->a_af || 1228 pai->ai_family == PF_UNSPEC /*?*/) { 1229 GET_AI(cur->ai_next, afd, pton); 1230 GET_PORT(cur->ai_next, servname); 1231 if ((pai->ai_flags & AI_CANONNAME)) { 1232 /* 1233 * Set the numeric address itself as 1234 * the canonical name, based on a 1235 * clarification in rfc3493. 1236 */ 1237 GET_CANONNAME(cur->ai_next, canonname); 1238 } 1239 while (cur && cur->ai_next) 1240 cur = cur->ai_next; 1241 } else 1242 ERR(EAI_FAMILY); /* XXX */ 1243 } 1244 break; 1245 } 1246 1247 *res = sentinel.ai_next; 1248 return 0; 1249 1250free: 1251bad: 1252 if (sentinel.ai_next) 1253 freeaddrinfo(sentinel.ai_next); 1254 return error; 1255} 1256 1257/* 1258 * numeric hostname with scope 1259 */ 1260static int 1261explore_numeric_scope(pai, hostname, servname, res) 1262 const struct addrinfo *pai; 1263 const char *hostname; 1264 const char *servname; 1265 struct addrinfo **res; 1266{ 1267#if !defined(SCOPE_DELIMITER) || !defined(INET6) 1268 return explore_numeric(pai, hostname, servname, res, hostname); 1269#else 1270 const struct afd *afd; 1271 struct addrinfo *cur; 1272 int error; 1273 char *cp, *hostname2 = NULL, *scope, *addr; 1274 struct sockaddr_in6 *sin6; 1275 1276 /* 1277 * if the servname does not match socktype/protocol, ignore it. 1278 */ 1279 if (get_portmatch(pai, servname) != 0) 1280 return 0; 1281 1282 afd = find_afd(pai->ai_family); 1283 if (afd == NULL) 1284 return 0; 1285 1286 if (!afd->a_scoped) 1287 return explore_numeric(pai, hostname, servname, res, hostname); 1288 1289 cp = strchr(hostname, SCOPE_DELIMITER); 1290 if (cp == NULL) 1291 return explore_numeric(pai, hostname, servname, res, hostname); 1292 1293 /* 1294 * Handle special case of <scoped_address><delimiter><scope id> 1295 */ 1296 hostname2 = strdup(hostname); 1297 if (hostname2 == NULL) 1298 return EAI_MEMORY; 1299 /* terminate at the delimiter */ 1300 hostname2[cp - hostname] = '\0'; 1301 addr = hostname2; 1302 scope = cp + 1; 1303 1304 error = explore_numeric(pai, addr, servname, res, hostname); 1305 if (error == 0) { 1306 u_int32_t scopeid; 1307 1308 for (cur = *res; cur; cur = cur->ai_next) { 1309 if (cur->ai_family != AF_INET6) 1310 continue; 1311 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1312 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1313 free(hostname2); 1314 return(EAI_NONAME); /* XXX: is return OK? */ 1315 } 1316 sin6->sin6_scope_id = scopeid; 1317 } 1318 } 1319 1320 free(hostname2); 1321 1322 return error; 1323#endif 1324} 1325 1326static int 1327get_canonname(pai, ai, str) 1328 const struct addrinfo *pai; 1329 struct addrinfo *ai; 1330 const char *str; 1331{ 1332 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1333 ai->ai_canonname = (char *)malloc(strlen(str) + 1); 1334 if (ai->ai_canonname == NULL) 1335 return EAI_MEMORY; 1336 strlcpy(ai->ai_canonname, str, strlen(str) + 1); 1337 } 1338 return 0; 1339} 1340 1341static struct addrinfo * 1342get_ai(pai, afd, addr) 1343 const struct addrinfo *pai; 1344 const struct afd *afd; 1345 const char *addr; 1346{ 1347 char *p; 1348 struct addrinfo *ai; 1349#ifdef FAITH 1350 struct in6_addr faith_prefix; 1351 char *fp_str; 1352 int translate = 0; 1353#endif 1354 1355#ifdef FAITH 1356 /* 1357 * Transfrom an IPv4 addr into a special IPv6 addr format for 1358 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1359 * 1360 * +-----------------------------------+------------+ 1361 * | faith prefix part (12 bytes) | embedded | 1362 * | | IPv4 addr part (4 bytes) 1363 * +-----------------------------------+------------+ 1364 * 1365 * faith prefix part is specified as ascii IPv6 addr format 1366 * in environmental variable GAI. 1367 * For FAITH to work correctly, routing to faith prefix must be 1368 * setup toward a machine where a FAITH daemon operates. 1369 * Also, the machine must enable some mechanizm 1370 * (e.g. faith interface hack) to divert those packet with 1371 * faith prefixed destination addr to user-land FAITH daemon. 1372 */ 1373 fp_str = getenv("GAI"); 1374 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1375 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1376 u_int32_t v4a; 1377 u_int8_t v4a_top; 1378 1379 memcpy(&v4a, addr, sizeof v4a); 1380 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1381 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1382 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1383 afd = &afdl[N_INET6]; 1384 memcpy(&faith_prefix.s6_addr[12], addr, 1385 sizeof(struct in_addr)); 1386 translate = 1; 1387 } 1388 } 1389#endif 1390 1391 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1392 + (afd->a_socklen)); 1393 if (ai == NULL) 1394 return NULL; 1395 1396 memcpy(ai, pai, sizeof(struct addrinfo)); 1397 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1398 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1399 ai->ai_addr->sa_len = afd->a_socklen; 1400 ai->ai_addrlen = afd->a_socklen; 1401 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1402 p = (char *)(void *)(ai->ai_addr); 1403#ifdef FAITH 1404 if (translate == 1) 1405 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1406 else 1407#endif 1408 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1409 return ai; 1410} 1411 1412static int 1413get_portmatch(ai, servname) 1414 const struct addrinfo *ai; 1415 const char *servname; 1416{ 1417 1418 /* get_port does not touch first argument. when matchonly == 1. */ 1419 /* LINTED const cast */ 1420 return get_port((struct addrinfo *)ai, servname, 1); 1421} 1422 1423static int 1424get_port(ai, servname, matchonly) 1425 struct addrinfo *ai; 1426 const char *servname; 1427 int matchonly; 1428{ 1429 const char *proto; 1430 struct servent *sp; 1431 int port; 1432 int allownumeric; 1433 1434 if (servname == NULL) 1435 return 0; 1436 switch (ai->ai_family) { 1437 case AF_INET: 1438#ifdef AF_INET6 1439 case AF_INET6: 1440#endif 1441 break; 1442 default: 1443 return 0; 1444 } 1445 1446 switch (ai->ai_socktype) { 1447 case SOCK_RAW: 1448 return EAI_SERVICE; 1449 case SOCK_DGRAM: 1450 case SOCK_STREAM: 1451 allownumeric = 1; 1452 break; 1453 case ANY: 1454 allownumeric = 0; 1455 break; 1456 default: 1457 return EAI_SOCKTYPE; 1458 } 1459 1460 if (str_isnumber(servname)) { 1461 if (!allownumeric) 1462 return EAI_SERVICE; 1463 port = atoi(servname); 1464 if (port < 0 || port > 65535) 1465 return EAI_SERVICE; 1466 port = htons(port); 1467 } else { 1468 switch (ai->ai_socktype) { 1469 case SOCK_DGRAM: 1470 proto = "udp"; 1471 break; 1472 case SOCK_STREAM: 1473 proto = "tcp"; 1474 break; 1475 default: 1476 proto = NULL; 1477 break; 1478 } 1479 1480 THREAD_LOCK(); 1481 if ((sp = getservbyname(servname, proto)) == NULL) { 1482 THREAD_UNLOCK(); 1483 return EAI_SERVICE; 1484 } 1485 port = sp->s_port; 1486 THREAD_UNLOCK(); 1487 } 1488 1489 if (!matchonly) { 1490 switch (ai->ai_family) { 1491 case AF_INET: 1492 ((struct sockaddr_in *)(void *) 1493 ai->ai_addr)->sin_port = port; 1494 break; 1495#ifdef INET6 1496 case AF_INET6: 1497 ((struct sockaddr_in6 *)(void *) 1498 ai->ai_addr)->sin6_port = port; 1499 break; 1500#endif 1501 } 1502 } 1503 1504 return 0; 1505} 1506 1507static const struct afd * 1508find_afd(af) 1509 int af; 1510{ 1511 const struct afd *afd; 1512 1513 if (af == PF_UNSPEC) 1514 return NULL; 1515 for (afd = afdl; afd->a_af; afd++) { 1516 if (afd->a_af == af) 1517 return afd; 1518 } 1519 return NULL; 1520} 1521 1522/* 1523 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1524 * will take care of it. 1525 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1526 * if the code is right or not. 1527 * 1528 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1529 * _dns_getaddrinfo. 1530 */ 1531static int 1532addrconfig(pai) 1533 struct addrinfo *pai; 1534{ 1535 int s, af; 1536 1537 /* 1538 * TODO: 1539 * Note that implementation dependent test for address 1540 * configuration should be done everytime called 1541 * (or apropriate interval), 1542 * because addresses will be dynamically assigned or deleted. 1543 */ 1544 af = pai->ai_family; 1545 if (af == AF_UNSPEC) { 1546 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1547 af = AF_INET; 1548 else { 1549 _close(s); 1550 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1551 af = AF_INET6; 1552 else 1553 _close(s); 1554 } 1555 } 1556 if (af != AF_UNSPEC) { 1557 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1558 return 0; 1559 _close(s); 1560 } 1561 pai->ai_family = af; 1562 return 1; 1563} 1564 1565#ifdef INET6 1566/* convert a string to a scope identifier. XXX: IPv6 specific */ 1567static int 1568ip6_str2scopeid(scope, sin6, scopeid) 1569 char *scope; 1570 struct sockaddr_in6 *sin6; 1571 u_int32_t *scopeid; 1572{ 1573 u_long lscopeid; 1574 struct in6_addr *a6; 1575 char *ep; 1576 1577 a6 = &sin6->sin6_addr; 1578 1579 /* empty scopeid portion is invalid */ 1580 if (*scope == '\0') 1581 return -1; 1582 1583 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1584 /* 1585 * We currently assume a one-to-one mapping between links 1586 * and interfaces, so we simply use interface indices for 1587 * like-local scopes. 1588 */ 1589 *scopeid = if_nametoindex(scope); 1590 if (*scopeid == 0) 1591 goto trynumeric; 1592 return 0; 1593 } 1594 1595 /* still unclear about literal, allow numeric only - placeholder */ 1596 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1597 goto trynumeric; 1598 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1599 goto trynumeric; 1600 else 1601 goto trynumeric; /* global */ 1602 1603 /* try to convert to a numeric id as a last resort */ 1604 trynumeric: 1605 errno = 0; 1606 lscopeid = strtoul(scope, &ep, 10); 1607 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1608 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1609 return 0; 1610 else 1611 return -1; 1612} 1613#endif 1614 1615/* 1616 * FQDN hostname, DNS lookup 1617 */ 1618static int 1619explore_fqdn(pai, hostname, servname, res) 1620 const struct addrinfo *pai; 1621 const char *hostname; 1622 const char *servname; 1623 struct addrinfo **res; 1624{ 1625 struct addrinfo *result; 1626 struct addrinfo *cur; 1627 int error = 0; 1628 static const ns_dtab dtab[] = { 1629 NS_FILES_CB(_files_getaddrinfo, NULL) 1630 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1631 NS_NIS_CB(_yp_getaddrinfo, NULL) 1632 { 0 } 1633 }; 1634 1635 result = NULL; 1636 1637 /* 1638 * if the servname does not match socktype/protocol, ignore it. 1639 */ 1640 if (get_portmatch(pai, servname) != 0) 1641 return 0; 1642 1643 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1644 default_dns_files, hostname, pai)) { 1645 case NS_TRYAGAIN: 1646 error = EAI_AGAIN; 1647 goto free; 1648 case NS_UNAVAIL: 1649 error = EAI_FAIL; 1650 goto free; 1651 case NS_NOTFOUND: 1652 error = EAI_NONAME; 1653 goto free; 1654 case NS_SUCCESS: 1655 error = 0; 1656 for (cur = result; cur; cur = cur->ai_next) { 1657 GET_PORT(cur, servname); 1658 /* canonname should be filled already */ 1659 } 1660 break; 1661 } 1662 1663 *res = result; 1664 1665 return 0; 1666 1667free: 1668 if (result) 1669 freeaddrinfo(result); 1670 return error; 1671} 1672 1673#ifdef DEBUG 1674static const char AskedForGot[] = 1675 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1676#endif 1677static FILE *hostf = NULL; 1678 1679static struct addrinfo * 1680getanswer(answer, anslen, qname, qtype, pai) 1681 const querybuf *answer; 1682 int anslen; 1683 const char *qname; 1684 int qtype; 1685 const struct addrinfo *pai; 1686{ 1687 struct addrinfo sentinel, *cur; 1688 struct addrinfo ai; 1689 const struct afd *afd; 1690 char *canonname; 1691 const HEADER *hp; 1692 const u_char *cp; 1693 int n; 1694 const u_char *eom; 1695 char *bp, *ep; 1696 int type, class, ancount, qdcount; 1697 int haveanswer, had_error; 1698 char tbuf[MAXDNAME]; 1699 int (*name_ok)(const char *); 1700 char hostbuf[8*1024]; 1701 1702 memset(&sentinel, 0, sizeof(sentinel)); 1703 cur = &sentinel; 1704 1705 canonname = NULL; 1706 eom = answer->buf + anslen; 1707 switch (qtype) { 1708 case T_A: 1709 case T_AAAA: 1710 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1711 name_ok = res_hnok; 1712 break; 1713 default: 1714 return (NULL); /* XXX should be abort(); */ 1715 } 1716 /* 1717 * find first satisfactory answer 1718 */ 1719 hp = &answer->hdr; 1720 ancount = ntohs(hp->ancount); 1721 qdcount = ntohs(hp->qdcount); 1722 bp = hostbuf; 1723 ep = hostbuf + sizeof hostbuf; 1724 cp = answer->buf + HFIXEDSZ; 1725 if (qdcount != 1) { 1726 h_errno = NO_RECOVERY; 1727 return (NULL); 1728 } 1729 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1730 if ((n < 0) || !(*name_ok)(bp)) { 1731 h_errno = NO_RECOVERY; 1732 return (NULL); 1733 } 1734 cp += n + QFIXEDSZ; 1735 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1736 /* res_send() has already verified that the query name is the 1737 * same as the one we sent; this just gets the expanded name 1738 * (i.e., with the succeeding search-domain tacked on). 1739 */ 1740 n = strlen(bp) + 1; /* for the \0 */ 1741 if (n >= MAXHOSTNAMELEN) { 1742 h_errno = NO_RECOVERY; 1743 return (NULL); 1744 } 1745 canonname = bp; 1746 bp += n; 1747 /* The qname can be abbreviated, but h_name is now absolute. */ 1748 qname = canonname; 1749 } 1750 haveanswer = 0; 1751 had_error = 0; 1752 while (ancount-- > 0 && cp < eom && !had_error) { 1753 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1754 if ((n < 0) || !(*name_ok)(bp)) { 1755 had_error++; 1756 continue; 1757 } 1758 cp += n; /* name */ 1759 type = _getshort(cp); 1760 cp += INT16SZ; /* type */ 1761 class = _getshort(cp); 1762 cp += INT16SZ + INT32SZ; /* class, TTL */ 1763 n = _getshort(cp); 1764 cp += INT16SZ; /* len */ 1765 if (class != C_IN) { 1766 /* XXX - debug? syslog? */ 1767 cp += n; 1768 continue; /* XXX - had_error++ ? */ 1769 } 1770 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1771 type == T_CNAME) { 1772 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1773 if ((n < 0) || !(*name_ok)(tbuf)) { 1774 had_error++; 1775 continue; 1776 } 1777 cp += n; 1778 /* Get canonical name. */ 1779 n = strlen(tbuf) + 1; /* for the \0 */ 1780 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1781 had_error++; 1782 continue; 1783 } 1784 strlcpy(bp, tbuf, ep - bp); 1785 canonname = bp; 1786 bp += n; 1787 continue; 1788 } 1789 if (qtype == T_ANY) { 1790 if (!(type == T_A || type == T_AAAA)) { 1791 cp += n; 1792 continue; 1793 } 1794 } else if (type != qtype) { 1795#ifdef DEBUG 1796 if (type != T_KEY && type != T_SIG) 1797 syslog(LOG_NOTICE|LOG_AUTH, 1798 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1799 qname, p_class(C_IN), p_type(qtype), 1800 p_type(type)); 1801#endif 1802 cp += n; 1803 continue; /* XXX - had_error++ ? */ 1804 } 1805 switch (type) { 1806 case T_A: 1807 case T_AAAA: 1808 if (strcasecmp(canonname, bp) != 0) { 1809#ifdef DEBUG 1810 syslog(LOG_NOTICE|LOG_AUTH, 1811 AskedForGot, canonname, bp); 1812#endif 1813 cp += n; 1814 continue; /* XXX - had_error++ ? */ 1815 } 1816 if (type == T_A && n != INADDRSZ) { 1817 cp += n; 1818 continue; 1819 } 1820 if (type == T_AAAA && n != IN6ADDRSZ) { 1821 cp += n; 1822 continue; 1823 } 1824#ifdef FILTER_V4MAPPED 1825 if (type == T_AAAA) { 1826 struct in6_addr in6; 1827 memcpy(&in6, cp, sizeof(in6)); 1828 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1829 cp += n; 1830 continue; 1831 } 1832 } 1833#endif 1834 if (!haveanswer) { 1835 int nn; 1836 1837 canonname = bp; 1838 nn = strlen(bp) + 1; /* for the \0 */ 1839 bp += nn; 1840 } 1841 1842 /* don't overwrite pai */ 1843 ai = *pai; 1844 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1845 afd = find_afd(ai.ai_family); 1846 if (afd == NULL) { 1847 cp += n; 1848 continue; 1849 } 1850 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1851 if (cur->ai_next == NULL) 1852 had_error++; 1853 while (cur && cur->ai_next) 1854 cur = cur->ai_next; 1855 cp += n; 1856 break; 1857 default: 1858 abort(); 1859 } 1860 if (!had_error) 1861 haveanswer++; 1862 } 1863 if (haveanswer) { 1864#if defined(RESOLVSORT) 1865 /* 1866 * We support only IPv4 address for backward 1867 * compatibility against gethostbyname(3). 1868 */ 1869 if (_res.nsort && qtype == T_A) { 1870 if (addr4sort(&sentinel) < 0) { 1871 freeaddrinfo(sentinel.ai_next); 1872 h_errno = NO_RECOVERY; 1873 return NULL; 1874 } 1875 } 1876#endif /*RESOLVSORT*/ 1877 if (!canonname) 1878 (void)get_canonname(pai, sentinel.ai_next, qname); 1879 else 1880 (void)get_canonname(pai, sentinel.ai_next, canonname); 1881 h_errno = NETDB_SUCCESS; 1882 return sentinel.ai_next; 1883 } 1884 1885 h_errno = NO_RECOVERY; 1886 return NULL; 1887} 1888 1889#ifdef RESOLVSORT 1890struct addr_ptr { 1891 struct addrinfo *ai; 1892 int aval; 1893}; 1894 1895static int 1896addr4sort(struct addrinfo *sentinel) 1897{ 1898 struct addrinfo *ai; 1899 struct addr_ptr *addrs, addr; 1900 struct sockaddr_in *sin; 1901 int naddrs, i, j; 1902 int needsort = 0; 1903 1904 if (!sentinel) 1905 return -1; 1906 naddrs = 0; 1907 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1908 naddrs++; 1909 if (naddrs < 2) 1910 return 0; /* We don't need sorting. */ 1911 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1912 return -1; 1913 i = 0; 1914 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1915 sin = (struct sockaddr_in *)ai->ai_addr; 1916 for (j = 0; (unsigned)j < _res.nsort; j++) { 1917 if (_res.sort_list[j].addr.s_addr == 1918 (sin->sin_addr.s_addr & _res.sort_list[j].mask)) 1919 break; 1920 } 1921 addrs[i].ai = ai; 1922 addrs[i].aval = j; 1923 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1924 needsort = i; 1925 i++; 1926 } 1927 if (!needsort) { 1928 free(addrs); 1929 return 0; 1930 } 1931 1932 while (needsort < naddrs) { 1933 for (j = needsort - 1; j >= 0; j--) { 1934 if (addrs[j].aval > addrs[j+1].aval) { 1935 addr = addrs[j]; 1936 addrs[j] = addrs[j + 1]; 1937 addrs[j + 1] = addr; 1938 } else 1939 break; 1940 } 1941 needsort++; 1942 } 1943 1944 ai = sentinel; 1945 for (i = 0; i < naddrs; ++i) { 1946 ai->ai_next = addrs[i].ai; 1947 ai = ai->ai_next; 1948 } 1949 ai->ai_next = NULL; 1950 free(addrs); 1951 return 0; 1952} 1953#endif /*RESOLVSORT*/ 1954 1955/*ARGSUSED*/ 1956static int 1957_dns_getaddrinfo(rv, cb_data, ap) 1958 void *rv; 1959 void *cb_data; 1960 va_list ap; 1961{ 1962 struct addrinfo *ai; 1963 querybuf *buf, *buf2; 1964 const char *hostname; 1965 const struct addrinfo *pai; 1966 struct addrinfo sentinel, *cur; 1967 struct res_target q, q2; 1968 1969 hostname = va_arg(ap, char *); 1970 pai = va_arg(ap, const struct addrinfo *); 1971 1972 memset(&q, 0, sizeof(q2)); 1973 memset(&q2, 0, sizeof(q2)); 1974 memset(&sentinel, 0, sizeof(sentinel)); 1975 cur = &sentinel; 1976 1977 buf = malloc(sizeof(*buf)); 1978 if (!buf) { 1979 h_errno = NETDB_INTERNAL; 1980 return NS_NOTFOUND; 1981 } 1982 buf2 = malloc(sizeof(*buf2)); 1983 if (!buf2) { 1984 free(buf); 1985 h_errno = NETDB_INTERNAL; 1986 return NS_NOTFOUND; 1987 } 1988 1989 switch (pai->ai_family) { 1990 case AF_UNSPEC: 1991 q.name = hostname; 1992 q.qclass = C_IN; 1993 q.qtype = T_A; 1994 q.answer = buf->buf; 1995 q.anslen = sizeof(buf->buf); 1996 q.next = &q2; 1997 q2.name = hostname; 1998 q2.qclass = C_IN; 1999 q2.qtype = T_AAAA; 2000 q2.answer = buf2->buf; 2001 q2.anslen = sizeof(buf2->buf); 2002 break; 2003 case AF_INET: 2004 q.name = hostname; 2005 q.qclass = C_IN; 2006 q.qtype = T_A; 2007 q.answer = buf->buf; 2008 q.anslen = sizeof(buf->buf); 2009 break; 2010 case AF_INET6: 2011 q.name = hostname; 2012 q.qclass = C_IN; 2013 q.qtype = T_AAAA; 2014 q.answer = buf->buf; 2015 q.anslen = sizeof(buf->buf); 2016 break; 2017 default: 2018 free(buf); 2019 free(buf2); 2020 return NS_UNAVAIL; 2021 } 2022 if (res_searchN(hostname, &q) < 0) { 2023 free(buf); 2024 free(buf2); 2025 return NS_NOTFOUND; 2026 } 2027 /* prefer IPv6 */ 2028 if (q.next) { 2029 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai); 2030 if (ai) { 2031 cur->ai_next = ai; 2032 while (cur && cur->ai_next) 2033 cur = cur->ai_next; 2034 } 2035 } 2036 ai = getanswer(buf, q.n, q.name, q.qtype, pai); 2037 if (ai) 2038 cur->ai_next = ai; 2039 free(buf); 2040 free(buf2); 2041 if (sentinel.ai_next == NULL) 2042 switch (h_errno) { 2043 case HOST_NOT_FOUND: 2044 return NS_NOTFOUND; 2045 case TRY_AGAIN: 2046 return NS_TRYAGAIN; 2047 default: 2048 return NS_UNAVAIL; 2049 } 2050 *((struct addrinfo **)rv) = sentinel.ai_next; 2051 return NS_SUCCESS; 2052} 2053 2054static void 2055_sethtent() 2056{ 2057 if (!hostf) 2058 hostf = fopen(_PATH_HOSTS, "r" ); 2059 else 2060 rewind(hostf); 2061} 2062 2063static void 2064_endhtent() 2065{ 2066 if (hostf) { 2067 (void) fclose(hostf); 2068 hostf = NULL; 2069 } 2070} 2071 2072static struct addrinfo * 2073_gethtent(name, pai) 2074 const char *name; 2075 const struct addrinfo *pai; 2076{ 2077 char *p; 2078 char *cp, *tname, *cname; 2079 struct addrinfo hints, *res0, *res; 2080 int error; 2081 const char *addr; 2082 char hostbuf[8*1024]; 2083 2084 if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) 2085 return (NULL); 2086again: 2087 if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) 2088 return (NULL); 2089 if (*p == '#') 2090 goto again; 2091 cp = strpbrk(p, "#\n"); 2092 if (cp != NULL) 2093 *cp = '\0'; 2094 if (!(cp = strpbrk(p, " \t"))) 2095 goto again; 2096 *cp++ = '\0'; 2097 addr = p; 2098 cname = NULL; 2099 /* if this is not something we're looking for, skip it. */ 2100 while (cp && *cp) { 2101 if (*cp == ' ' || *cp == '\t') { 2102 cp++; 2103 continue; 2104 } 2105 tname = cp; 2106 if (cname == NULL) 2107 cname = cp; 2108 if ((cp = strpbrk(cp, " \t")) != NULL) 2109 *cp++ = '\0'; 2110 if (strcasecmp(name, tname) == 0) 2111 goto found; 2112 } 2113 goto again; 2114 2115found: 2116 /* we should not glob socktype/protocol here */ 2117 memset(&hints, 0, sizeof(hints)); 2118 hints.ai_family = pai->ai_family; 2119 hints.ai_socktype = SOCK_DGRAM; 2120 hints.ai_protocol = 0; 2121 hints.ai_flags = AI_NUMERICHOST; 2122 error = getaddrinfo(addr, "0", &hints, &res0); 2123 if (error) 2124 goto again; 2125#ifdef FILTER_V4MAPPED 2126 /* XXX should check all items in the chain */ 2127 if (res0->ai_family == AF_INET6 && 2128 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2129 freeaddrinfo(res0); 2130 goto again; 2131 } 2132#endif 2133 for (res = res0; res; res = res->ai_next) { 2134 /* cover it up */ 2135 res->ai_flags = pai->ai_flags; 2136 res->ai_socktype = pai->ai_socktype; 2137 res->ai_protocol = pai->ai_protocol; 2138 2139 if (pai->ai_flags & AI_CANONNAME) { 2140 if (get_canonname(pai, res, cname) != 0) { 2141 freeaddrinfo(res0); 2142 goto again; 2143 } 2144 } 2145 } 2146 return res0; 2147} 2148 2149/*ARGSUSED*/ 2150static int 2151_files_getaddrinfo(rv, cb_data, ap) 2152 void *rv; 2153 void *cb_data; 2154 va_list ap; 2155{ 2156 const char *name; 2157 const struct addrinfo *pai; 2158 struct addrinfo sentinel, *cur; 2159 struct addrinfo *p; 2160 2161 name = va_arg(ap, char *); 2162 pai = va_arg(ap, struct addrinfo *); 2163 2164 memset(&sentinel, 0, sizeof(sentinel)); 2165 cur = &sentinel; 2166 2167 THREAD_LOCK(); 2168 _sethtent(); 2169 while ((p = _gethtent(name, pai)) != NULL) { 2170 cur->ai_next = p; 2171 while (cur && cur->ai_next) 2172 cur = cur->ai_next; 2173 } 2174 _endhtent(); 2175 THREAD_UNLOCK(); 2176 2177 *((struct addrinfo **)rv) = sentinel.ai_next; 2178 if (sentinel.ai_next == NULL) 2179 return NS_NOTFOUND; 2180 return NS_SUCCESS; 2181} 2182 2183#ifdef YP 2184static char *__ypdomain; 2185 2186/*ARGSUSED*/ 2187static struct addrinfo * 2188_yphostent(line, pai) 2189 char *line; 2190 const struct addrinfo *pai; 2191{ 2192 struct addrinfo sentinel, *cur; 2193 struct addrinfo hints, *res, *res0; 2194 int error; 2195 char *p = line; 2196 const char *addr, *canonname; 2197 char *nextline; 2198 char *cp; 2199 2200 addr = canonname = NULL; 2201 2202 memset(&sentinel, 0, sizeof(sentinel)); 2203 cur = &sentinel; 2204 2205nextline: 2206 /* terminate line */ 2207 cp = strchr(p, '\n'); 2208 if (cp) { 2209 *cp++ = '\0'; 2210 nextline = cp; 2211 } else 2212 nextline = NULL; 2213 2214 cp = strpbrk(p, " \t"); 2215 if (cp == NULL) { 2216 if (canonname == NULL) 2217 return (NULL); 2218 else 2219 goto done; 2220 } 2221 *cp++ = '\0'; 2222 2223 addr = p; 2224 2225 while (cp && *cp) { 2226 if (*cp == ' ' || *cp == '\t') { 2227 cp++; 2228 continue; 2229 } 2230 if (!canonname) 2231 canonname = cp; 2232 if ((cp = strpbrk(cp, " \t")) != NULL) 2233 *cp++ = '\0'; 2234 } 2235 2236 hints = *pai; 2237 hints.ai_flags = AI_NUMERICHOST; 2238 error = getaddrinfo(addr, NULL, &hints, &res0); 2239 if (error == 0) { 2240 for (res = res0; res; res = res->ai_next) { 2241 /* cover it up */ 2242 res->ai_flags = pai->ai_flags; 2243 2244 if (pai->ai_flags & AI_CANONNAME) 2245 (void)get_canonname(pai, res, canonname); 2246 } 2247 } else 2248 res0 = NULL; 2249 if (res0) { 2250 cur->ai_next = res0; 2251 while (cur && cur->ai_next) 2252 cur = cur->ai_next; 2253 } 2254 2255 if (nextline) { 2256 p = nextline; 2257 goto nextline; 2258 } 2259 2260done: 2261 return sentinel.ai_next; 2262} 2263 2264/*ARGSUSED*/ 2265static int 2266_yp_getaddrinfo(rv, cb_data, ap) 2267 void *rv; 2268 void *cb_data; 2269 va_list ap; 2270{ 2271 struct addrinfo sentinel, *cur; 2272 struct addrinfo *ai = NULL; 2273 static char *__ypcurrent; 2274 int __ypcurrentlen, r; 2275 const char *name; 2276 const struct addrinfo *pai; 2277 2278 name = va_arg(ap, char *); 2279 pai = va_arg(ap, const struct addrinfo *); 2280 2281 memset(&sentinel, 0, sizeof(sentinel)); 2282 cur = &sentinel; 2283 2284 THREAD_LOCK(); 2285 if (!__ypdomain) { 2286 if (_yp_check(&__ypdomain) == 0) { 2287 THREAD_UNLOCK(); 2288 return NS_UNAVAIL; 2289 } 2290 } 2291 if (__ypcurrent) 2292 free(__ypcurrent); 2293 __ypcurrent = NULL; 2294 2295 /* hosts.byname is only for IPv4 (Solaris8) */ 2296 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2297 r = yp_match(__ypdomain, "hosts.byname", name, 2298 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 2299 if (r == 0) { 2300 struct addrinfo ai4; 2301 2302 ai4 = *pai; 2303 ai4.ai_family = AF_INET; 2304 ai = _yphostent(__ypcurrent, &ai4); 2305 if (ai) { 2306 cur->ai_next = ai; 2307 while (cur && cur->ai_next) 2308 cur = cur->ai_next; 2309 } 2310 } 2311 } 2312 2313 /* ipnodes.byname can hold both IPv4/v6 */ 2314 r = yp_match(__ypdomain, "ipnodes.byname", name, 2315 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 2316 if (r == 0) { 2317 ai = _yphostent(__ypcurrent, pai); 2318 if (ai) { 2319 cur->ai_next = ai; 2320 while (cur && cur->ai_next) 2321 cur = cur->ai_next; 2322 } 2323 } 2324 THREAD_UNLOCK(); 2325 2326 if (sentinel.ai_next == NULL) { 2327 h_errno = HOST_NOT_FOUND; 2328 return NS_NOTFOUND; 2329 } 2330 *((struct addrinfo **)rv) = sentinel.ai_next; 2331 return NS_SUCCESS; 2332} 2333#endif 2334 2335/* resolver logic */ 2336 2337extern const char *__hostalias(const char *); 2338 2339/* 2340 * Formulate a normal query, send, and await answer. 2341 * Returned answer is placed in supplied buffer "answer". 2342 * Perform preliminary check of answer, returning success only 2343 * if no error is indicated and the answer count is nonzero. 2344 * Return the size of the response on success, -1 on error. 2345 * Error number is left in h_errno. 2346 * 2347 * Caller must parse answer and determine whether it answers the question. 2348 */ 2349static int 2350res_queryN(name, target) 2351 const char *name; /* domain name */ 2352 struct res_target *target; 2353{ 2354 u_char *buf; 2355 HEADER *hp; 2356 int n; 2357 struct res_target *t; 2358 int rcode; 2359 int ancount; 2360 2361 rcode = NOERROR; 2362 ancount = 0; 2363 2364 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2365 h_errno = NETDB_INTERNAL; 2366 return (-1); 2367 } 2368 2369 buf = malloc(MAXPACKET); 2370 if (!buf) { 2371 h_errno = NETDB_INTERNAL; 2372 return -1; 2373 } 2374 2375 for (t = target; t; t = t->next) { 2376 int class, type; 2377 u_char *answer; 2378 int anslen; 2379 2380 hp = (HEADER *)(void *)t->answer; 2381 hp->rcode = NOERROR; /* default */ 2382 2383 /* make it easier... */ 2384 class = t->qclass; 2385 type = t->qtype; 2386 answer = t->answer; 2387 anslen = t->anslen; 2388#ifdef DEBUG 2389 if (_res.options & RES_DEBUG) 2390 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2391#endif 2392 2393 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, 2394 buf, MAXPACKET); 2395 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) 2396 n = res_opt(n, buf, MAXPACKET, anslen); 2397 if (n <= 0) { 2398#ifdef DEBUG 2399 if (_res.options & RES_DEBUG) 2400 printf(";; res_query: mkquery failed\n"); 2401#endif 2402 free(buf); 2403 h_errno = NO_RECOVERY; 2404 return (n); 2405 } 2406 n = res_send(buf, n, answer, anslen); 2407#if 0 2408 if (n < 0) { 2409#ifdef DEBUG 2410 if (_res.options & RES_DEBUG) 2411 printf(";; res_query: send error\n"); 2412#endif 2413 free(buf); 2414 h_errno = TRY_AGAIN; 2415 return (n); 2416 } 2417#endif 2418 2419 if (n < 0 || n > anslen) 2420 hp->rcode = FORMERR; /* XXX not very informative */ 2421 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2422 rcode = hp->rcode; /* record most recent error */ 2423#ifdef DEBUG 2424 if (_res.options & RES_DEBUG) 2425 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2426 ntohs(hp->ancount)); 2427#endif 2428 continue; 2429 } 2430 2431 ancount += ntohs(hp->ancount); 2432 2433 t->n = n; 2434 } 2435 2436 free(buf); 2437 2438 if (ancount == 0) { 2439 switch (rcode) { 2440 case NXDOMAIN: 2441 h_errno = HOST_NOT_FOUND; 2442 break; 2443 case SERVFAIL: 2444 h_errno = TRY_AGAIN; 2445 break; 2446 case NOERROR: 2447 h_errno = NO_DATA; 2448 break; 2449 case FORMERR: 2450 case NOTIMP: 2451 case REFUSED: 2452 default: 2453 h_errno = NO_RECOVERY; 2454 break; 2455 } 2456 return (-1); 2457 } 2458 return (ancount); 2459} 2460 2461/* 2462 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2463 * Return the size of the response on success, -1 on error. 2464 * If enabled, implement search rules until answer or unrecoverable failure 2465 * is detected. Error code, if any, is left in h_errno. 2466 */ 2467static int 2468res_searchN(name, target) 2469 const char *name; /* domain name */ 2470 struct res_target *target; 2471{ 2472 const char *cp, * const *domain; 2473 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2474 u_int dots; 2475 int trailing_dot, ret, saved_herrno; 2476 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 2477 2478 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2479 h_errno = NETDB_INTERNAL; 2480 return (-1); 2481 } 2482 2483 errno = 0; 2484 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 2485 dots = 0; 2486 for (cp = name; *cp; cp++) 2487 dots += (*cp == '.'); 2488 trailing_dot = 0; 2489 if (cp > name && *--cp == '.') 2490 trailing_dot++; 2491 2492 /* 2493 * if there aren't any dots, it could be a user-level alias 2494 */ 2495 if (!dots && (cp = __hostalias(name)) != NULL) 2496 return (res_queryN(cp, target)); 2497 2498 /* 2499 * If there are dots in the name already, let's just give it a try 2500 * 'as is'. The threshold can be set with the "ndots" option. 2501 */ 2502 saved_herrno = -1; 2503 if (dots >= _res.ndots) { 2504 ret = res_querydomainN(name, NULL, target); 2505 if (ret > 0) 2506 return (ret); 2507 saved_herrno = h_errno; 2508 tried_as_is++; 2509 } 2510 2511 /* 2512 * We do at least one level of search if 2513 * - there is no dot and RES_DEFNAME is set, or 2514 * - there is at least one dot, there is no trailing dot, 2515 * and RES_DNSRCH is set. 2516 */ 2517 if ((!dots && (_res.options & RES_DEFNAMES)) || 2518 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { 2519 int done = 0; 2520 2521 for (domain = (const char * const *)_res.dnsrch; 2522 *domain && !done; 2523 domain++) { 2524 2525 ret = res_querydomainN(name, *domain, target); 2526 if (ret > 0) 2527 return (ret); 2528 2529 /* 2530 * If no server present, give up. 2531 * If name isn't found in this domain, 2532 * keep trying higher domains in the search list 2533 * (if that's enabled). 2534 * On a NO_DATA error, keep trying, otherwise 2535 * a wildcard entry of another type could keep us 2536 * from finding this entry higher in the domain. 2537 * If we get some other error (negative answer or 2538 * server failure), then stop searching up, 2539 * but try the input name below in case it's 2540 * fully-qualified. 2541 */ 2542 if (errno == ECONNREFUSED) { 2543 h_errno = TRY_AGAIN; 2544 return (-1); 2545 } 2546 2547 switch (h_errno) { 2548 case NO_DATA: 2549 got_nodata++; 2550 /* FALLTHROUGH */ 2551 case HOST_NOT_FOUND: 2552 /* keep trying */ 2553 break; 2554 case TRY_AGAIN: 2555 if (hp->rcode == SERVFAIL) { 2556 /* try next search element, if any */ 2557 got_servfail++; 2558 break; 2559 } 2560 /* FALLTHROUGH */ 2561 default: 2562 /* anything else implies that we're done */ 2563 done++; 2564 } 2565 /* 2566 * if we got here for some reason other than DNSRCH, 2567 * we only wanted one iteration of the loop, so stop. 2568 */ 2569 if (!(_res.options & RES_DNSRCH)) 2570 done++; 2571 } 2572 } 2573 2574 /* 2575 * if we have not already tried the name "as is", do that now. 2576 * note that we do this regardless of how many dots were in the 2577 * name or whether it ends with a dot. 2578 */ 2579 if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) { 2580 ret = res_querydomainN(name, NULL, target); 2581 if (ret > 0) 2582 return (ret); 2583 } 2584 2585 /* 2586 * if we got here, we didn't satisfy the search. 2587 * if we did an initial full query, return that query's h_errno 2588 * (note that we wouldn't be here if that query had succeeded). 2589 * else if we ever got a nodata, send that back as the reason. 2590 * else send back meaningless h_errno, that being the one from 2591 * the last DNSRCH we did. 2592 */ 2593 if (saved_herrno != -1) 2594 h_errno = saved_herrno; 2595 else if (got_nodata) 2596 h_errno = NO_DATA; 2597 else if (got_servfail) 2598 h_errno = TRY_AGAIN; 2599 return (-1); 2600} 2601 2602/* 2603 * Perform a call on res_query on the concatenation of name and domain, 2604 * removing a trailing dot from name if domain is NULL. 2605 */ 2606static int 2607res_querydomainN(name, domain, target) 2608 const char *name, *domain; 2609 struct res_target *target; 2610{ 2611 char nbuf[MAXDNAME]; 2612 const char *longname = nbuf; 2613 size_t n, d; 2614 2615 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2616 h_errno = NETDB_INTERNAL; 2617 return (-1); 2618 } 2619#ifdef DEBUG 2620 if (_res.options & RES_DEBUG) 2621 printf(";; res_querydomain(%s, %s)\n", 2622 name, domain?domain:"<Nil>"); 2623#endif 2624 if (domain == NULL) { 2625 /* 2626 * Check for trailing '.'; 2627 * copy without '.' if present. 2628 */ 2629 n = strlen(name); 2630 if (n >= MAXDNAME) { 2631 h_errno = NO_RECOVERY; 2632 return (-1); 2633 } 2634 if (n > 0 && name[--n] == '.') { 2635 strncpy(nbuf, name, n); 2636 nbuf[n] = '\0'; 2637 } else 2638 longname = name; 2639 } else { 2640 n = strlen(name); 2641 d = strlen(domain); 2642 if (n + d + 1 >= MAXDNAME) { 2643 h_errno = NO_RECOVERY; 2644 return (-1); 2645 } 2646 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2647 } 2648 return (res_queryN(longname, target)); 2649} 2650