getaddrinfo.c revision 141908
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 141908 2005-02-14 11:33:12Z phantom $"); 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 str2number(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 *); 287 288/* Entries EAI_ADDRFAMILY (1) and EAI_NODATA (7) are obsoleted, but left */ 289/* for backward compatibility with userland code prior to 2553bis-02 */ 290static const char *ai_errlist[] = { 291 "Success", /* 0 */ 292 "Address family for hostname not supported", /* 1 */ 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 "No address associated with hostname", /* 7 */ 299 "hostname nor servname provided, or not known", /* EAI_NONAME */ 300 "servname not supported for ai_socktype", /* EAI_SERVICE */ 301 "ai_socktype not supported", /* EAI_SOCKTYPE */ 302 "System error returned in errno", /* EAI_SYSTEM */ 303 "Invalid value for hints", /* EAI_BADHINTS */ 304 "Resolved protocol is unknown" /* EAI_PROTOCOL */ 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 */ 313pthread_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) \ 322do { \ 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) \ 332do { \ 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) \ 340do { \ 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) \ 348do { \ 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 360const char * 361gai_strerror(int ecode) 362{ 363 if (ecode >= 0 && ecode < EAI_MAX) 364 return ai_errlist[ecode]; 365 return "Unknown error"; 366} 367 368void 369freeaddrinfo(ai) 370 struct addrinfo *ai; 371{ 372 struct addrinfo *next; 373 374 do { 375 next = ai->ai_next; 376 if (ai->ai_canonname) 377 free(ai->ai_canonname); 378 /* no need to free(ai->ai_addr) */ 379 free(ai); 380 ai = next; 381 } while (ai); 382} 383 384static int 385str2number(p) 386 const char *p; 387{ 388 char *ep; 389 unsigned long v; 390 391 if (*p == '\0') 392 return -1; 393 ep = NULL; 394 errno = 0; 395 v = strtoul(p, &ep, 10); 396 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) 397 return v; 398 else 399 return -1; 400} 401 402int 403getaddrinfo(hostname, servname, hints, res) 404 const char *hostname, *servname; 405 const struct addrinfo *hints; 406 struct addrinfo **res; 407{ 408 struct addrinfo sentinel; 409 struct addrinfo *cur; 410 int error = 0; 411 struct addrinfo ai; 412 struct addrinfo ai0; 413 struct addrinfo *pai; 414 const struct explore *ex; 415 int numeric = 0; 416 417 memset(&sentinel, 0, sizeof(sentinel)); 418 cur = &sentinel; 419 pai = &ai; 420 pai->ai_flags = 0; 421 pai->ai_family = PF_UNSPEC; 422 pai->ai_socktype = ANY; 423 pai->ai_protocol = ANY; 424 pai->ai_addrlen = 0; 425 pai->ai_canonname = NULL; 426 pai->ai_addr = NULL; 427 pai->ai_next = NULL; 428 429 if (hostname == NULL && servname == NULL) 430 return EAI_NONAME; 431 if (hints) { 432 /* error check for hints */ 433 if (hints->ai_addrlen || hints->ai_canonname || 434 hints->ai_addr || hints->ai_next) 435 ERR(EAI_BADHINTS); /* xxx */ 436 if (hints->ai_flags & ~AI_MASK) 437 ERR(EAI_BADFLAGS); 438 switch (hints->ai_family) { 439 case PF_UNSPEC: 440 case PF_INET: 441#ifdef INET6 442 case PF_INET6: 443#endif 444 break; 445 default: 446 ERR(EAI_FAMILY); 447 } 448 memcpy(pai, hints, sizeof(*pai)); 449 450 /* 451 * if both socktype/protocol are specified, check if they 452 * are meaningful combination. 453 */ 454 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 455 for (ex = explore; ex->e_af >= 0; ex++) { 456 if (pai->ai_family != ex->e_af) 457 continue; 458 if (ex->e_socktype == ANY) 459 continue; 460 if (ex->e_protocol == ANY) 461 continue; 462 if (pai->ai_socktype == ex->e_socktype && 463 pai->ai_protocol != ex->e_protocol) { 464 ERR(EAI_BADHINTS); 465 } 466 } 467 } 468 } 469 470 /* 471 * post-2553: AI_ALL and AI_V4MAPPED are effective only against 472 * AF_INET6 query. They need to be ignored if specified in other 473 * occassions. 474 */ 475 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 476 case AI_V4MAPPED: 477 case AI_ALL | AI_V4MAPPED: 478 if (pai->ai_family != AF_INET6) 479 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 480 break; 481 case AI_ALL: 482#if 1 483 /* illegal */ 484 ERR(EAI_BADFLAGS); 485#else 486 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 487#endif 488 break; 489 } 490 491 /* 492 * check for special cases. (1) numeric servname is disallowed if 493 * socktype/protocol are left unspecified. (2) servname is disallowed 494 * for raw and other inet{,6} sockets. 495 */ 496 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 497#ifdef PF_INET6 498 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 499#endif 500 ) { 501 ai0 = *pai; /* backup *pai */ 502 503 if (pai->ai_family == PF_UNSPEC) { 504#ifdef PF_INET6 505 pai->ai_family = PF_INET6; 506#else 507 pai->ai_family = PF_INET; 508#endif 509 } 510 error = get_portmatch(pai, servname); 511 if (error) 512 ERR(error); 513 514 *pai = ai0; 515 } 516 517 ai0 = *pai; 518 519 /* NULL hostname, or numeric hostname */ 520 for (ex = explore; ex->e_af >= 0; ex++) { 521 *pai = ai0; 522 523 /* PF_UNSPEC entries are prepared for DNS queries only */ 524 if (ex->e_af == PF_UNSPEC) 525 continue; 526 527 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 528 continue; 529 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 530 continue; 531 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 532 continue; 533 534 if (pai->ai_family == PF_UNSPEC) 535 pai->ai_family = ex->e_af; 536 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 537 pai->ai_socktype = ex->e_socktype; 538 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 539 pai->ai_protocol = ex->e_protocol; 540 541 if (hostname == NULL) 542 error = explore_null(pai, servname, &cur->ai_next); 543 else 544 error = explore_numeric_scope(pai, hostname, servname, 545 &cur->ai_next); 546 547 if (error) 548 goto free; 549 550 while (cur && cur->ai_next) 551 cur = cur->ai_next; 552 } 553 554 /* 555 * XXX 556 * If numreic representation of AF1 can be interpreted as FQDN 557 * representation of AF2, we need to think again about the code below. 558 */ 559 if (sentinel.ai_next) { 560 numeric = 1; 561 goto good; 562 } 563 564 if (hostname == NULL) 565 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 566 if (pai->ai_flags & AI_NUMERICHOST) 567 ERR(EAI_NONAME); 568 569 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 570 ERR(EAI_FAIL); 571 572 /* 573 * hostname as alphabetical name. 574 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 575 * outer loop by AFs. 576 */ 577 for (ex = explore; ex->e_af >= 0; ex++) { 578 *pai = ai0; 579 580 /* require exact match for family field */ 581 if (pai->ai_family != ex->e_af) 582 continue; 583 584 if (!MATCH(pai->ai_socktype, ex->e_socktype, 585 WILD_SOCKTYPE(ex))) { 586 continue; 587 } 588 if (!MATCH(pai->ai_protocol, ex->e_protocol, 589 WILD_PROTOCOL(ex))) { 590 continue; 591 } 592 593 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 594 pai->ai_socktype = ex->e_socktype; 595 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 596 pai->ai_protocol = ex->e_protocol; 597 598 error = explore_fqdn(pai, hostname, servname, 599 &cur->ai_next); 600 601 while (cur && cur->ai_next) 602 cur = cur->ai_next; 603 } 604 605 /* XXX inhibit errors if we have the result */ 606 if (sentinel.ai_next) 607 error = 0; 608 609good: 610 /* 611 * ensure we return either: 612 * - error == 0, non-NULL *res 613 * - error != 0, NULL *res 614 */ 615 if (error == 0) { 616 if (sentinel.ai_next) { 617 /* 618 * If the returned entry is for an active connection, 619 * and the given name is not numeric, reorder the 620 * list, so that the application would try the list 621 * in the most efficient order. 622 */ 623 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 624 if (!numeric) 625 (void)reorder(&sentinel); 626 } 627 *res = sentinel.ai_next; 628 return SUCCESS; 629 } else 630 error = EAI_FAIL; 631 } 632free: 633bad: 634 if (sentinel.ai_next) 635 freeaddrinfo(sentinel.ai_next); 636 *res = NULL; 637 return error; 638} 639 640static int 641reorder(sentinel) 642 struct addrinfo *sentinel; 643{ 644 struct addrinfo *ai, **aip; 645 struct ai_order *aio; 646 int i, n; 647 struct policyhead policyhead; 648 649 /* count the number of addrinfo elements for sorting. */ 650 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 651 ; 652 653 /* 654 * If the number is small enough, we can skip the reordering process. 655 */ 656 if (n <= 1) 657 return(n); 658 659 /* allocate a temporary array for sort and initialization of it. */ 660 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 661 return(n); /* give up reordering */ 662 memset(aio, 0, sizeof(*aio) * n); 663 664 /* retrieve address selection policy from the kernel */ 665 TAILQ_INIT(&policyhead); 666 if (!get_addrselectpolicy(&policyhead)) { 667 /* no policy is installed into kernel, we don't sort. */ 668 free(aio); 669 return (n); 670 } 671 672 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 673 aio[i].aio_ai = ai; 674 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 675 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 676 &policyhead); 677 set_source(&aio[i], &policyhead); 678 } 679 680 /* perform sorting. */ 681 qsort(aio, n, sizeof(*aio), comp_dst); 682 683 /* reorder the addrinfo chain. */ 684 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 685 *aip = aio[i].aio_ai; 686 aip = &aio[i].aio_ai->ai_next; 687 } 688 *aip = NULL; 689 690 /* cleanup and return */ 691 free(aio); 692 free_addrselectpolicy(&policyhead); 693 return(n); 694} 695 696static int 697get_addrselectpolicy(head) 698 struct policyhead *head; 699{ 700#ifdef INET6 701 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 702 size_t l; 703 char *buf; 704 struct in6_addrpolicy *pol, *ep; 705 706 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 707 return (0); 708 if ((buf = malloc(l)) == NULL) 709 return (0); 710 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 711 free(buf); 712 return (0); 713 } 714 715 ep = (struct in6_addrpolicy *)(buf + l); 716 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 717 struct policyqueue *new; 718 719 if ((new = malloc(sizeof(*new))) == NULL) { 720 free_addrselectpolicy(head); /* make the list empty */ 721 break; 722 } 723 new->pc_policy = *pol; 724 TAILQ_INSERT_TAIL(head, new, pc_entry); 725 } 726 727 free(buf); 728 return (1); 729#else 730 return (0); 731#endif 732} 733 734static void 735free_addrselectpolicy(head) 736 struct policyhead *head; 737{ 738 struct policyqueue *ent, *nent; 739 740 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 741 nent = TAILQ_NEXT(ent, pc_entry); 742 TAILQ_REMOVE(head, ent, pc_entry); 743 free(ent); 744 } 745} 746 747static struct policyqueue * 748match_addrselectpolicy(addr, head) 749 struct sockaddr *addr; 750 struct policyhead *head; 751{ 752#ifdef INET6 753 struct policyqueue *ent, *bestent = NULL; 754 struct in6_addrpolicy *pol; 755 int matchlen, bestmatchlen = -1; 756 u_char *mp, *ep, *k, *p, m; 757 struct sockaddr_in6 key; 758 759 switch(addr->sa_family) { 760 case AF_INET6: 761 key = *(struct sockaddr_in6 *)addr; 762 break; 763 case AF_INET: 764 /* convert the address into IPv4-mapped IPv6 address. */ 765 memset(&key, 0, sizeof(key)); 766 key.sin6_family = AF_INET6; 767 key.sin6_len = sizeof(key); 768 key.sin6_addr.s6_addr[10] = 0xff; 769 key.sin6_addr.s6_addr[11] = 0xff; 770 memcpy(&key.sin6_addr.s6_addr[12], 771 &((struct sockaddr_in *)addr)->sin_addr, 4); 772 break; 773 default: 774 return(NULL); 775 } 776 777 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 778 pol = &ent->pc_policy; 779 matchlen = 0; 780 781 mp = (u_char *)&pol->addrmask.sin6_addr; 782 ep = mp + 16; /* XXX: scope field? */ 783 k = (u_char *)&key.sin6_addr; 784 p = (u_char *)&pol->addr.sin6_addr; 785 for (; mp < ep && *mp; mp++, k++, p++) { 786 m = *mp; 787 if ((*k & m) != *p) 788 goto next; /* not match */ 789 if (m == 0xff) /* short cut for a typical case */ 790 matchlen += 8; 791 else { 792 while (m >= 0x80) { 793 matchlen++; 794 m <<= 1; 795 } 796 } 797 } 798 799 /* matched. check if this is better than the current best. */ 800 if (matchlen > bestmatchlen) { 801 bestent = ent; 802 bestmatchlen = matchlen; 803 } 804 805 next: 806 continue; 807 } 808 809 return(bestent); 810#else 811 return(NULL); 812#endif 813 814} 815 816static void 817set_source(aio, ph) 818 struct ai_order *aio; 819 struct policyhead *ph; 820{ 821 struct addrinfo ai = *aio->aio_ai; 822 struct sockaddr_storage ss; 823 int s, srclen; 824 825 /* set unspec ("no source is available"), just in case */ 826 aio->aio_srcsa.sa_family = AF_UNSPEC; 827 aio->aio_srcscope = -1; 828 829 switch(ai.ai_family) { 830 case AF_INET: 831#ifdef INET6 832 case AF_INET6: 833#endif 834 break; 835 default: /* ignore unsupported AFs explicitly */ 836 return; 837 } 838 839 /* XXX: make a dummy addrinfo to call connect() */ 840 ai.ai_socktype = SOCK_DGRAM; 841 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 842 ai.ai_next = NULL; 843 memset(&ss, 0, sizeof(ss)); 844 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 845 ai.ai_addr = (struct sockaddr *)&ss; 846 get_port(&ai, "1", 0); 847 848 /* open a socket to get the source address for the given dst */ 849 if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0) 850 return; /* give up */ 851 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 852 goto cleanup; 853 srclen = ai.ai_addrlen; 854 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 855 aio->aio_srcsa.sa_family = AF_UNSPEC; 856 goto cleanup; 857 } 858 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 859 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 860 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 861#ifdef INET6 862 if (ai.ai_family == AF_INET6) { 863 struct in6_ifreq ifr6; 864 u_int32_t flags6; 865 866 /* XXX: interface name should not be hardcoded */ 867 strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name)); 868 memset(&ifr6, 0, sizeof(ifr6)); 869 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 870 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 871 flags6 = ifr6.ifr_ifru.ifru_flags6; 872 if ((flags6 & IN6_IFF_DEPRECATED)) 873 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 874 } 875 } 876#endif 877 878 cleanup: 879 _close(s); 880 return; 881} 882 883static int 884matchlen(src, dst) 885 struct sockaddr *src, *dst; 886{ 887 int match = 0; 888 u_char *s, *d; 889 u_char *lim, r; 890 int addrlen; 891 892 switch (src->sa_family) { 893#ifdef INET6 894 case AF_INET6: 895 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 896 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 897 addrlen = sizeof(struct in6_addr); 898 lim = s + addrlen; 899 break; 900#endif 901 case AF_INET: 902 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 903 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 904 addrlen = sizeof(struct in_addr); 905 lim = s + addrlen; 906 break; 907 default: 908 return(0); 909 } 910 911 while (s < lim) 912 if ((r = (*d++ ^ *s++)) != 0) { 913 while (r < addrlen * 8) { 914 match++; 915 r <<= 1; 916 } 917 break; 918 } else 919 match += 8; 920 return(match); 921} 922 923static int 924comp_dst(arg1, arg2) 925 const void *arg1, *arg2; 926{ 927 const struct ai_order *dst1 = arg1, *dst2 = arg2; 928 929 /* 930 * Rule 1: Avoid unusable destinations. 931 * XXX: we currently do not consider if an appropriate route exists. 932 */ 933 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 934 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 935 return(-1); 936 } 937 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 938 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 939 return(1); 940 } 941 942 /* Rule 2: Prefer matching scope. */ 943 if (dst1->aio_dstscope == dst1->aio_srcscope && 944 dst2->aio_dstscope != dst2->aio_srcscope) { 945 return(-1); 946 } 947 if (dst1->aio_dstscope != dst1->aio_srcscope && 948 dst2->aio_dstscope == dst2->aio_srcscope) { 949 return(1); 950 } 951 952 /* Rule 3: Avoid deprecated addresses. */ 953 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 954 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 955 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 956 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 957 return(-1); 958 } 959 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 960 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 961 return(1); 962 } 963 } 964 965 /* Rule 4: Prefer home addresses. */ 966 /* XXX: not implemented yet */ 967 968 /* Rule 5: Prefer matching label. */ 969#ifdef INET6 970 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 971 dst1->aio_srcpolicy->pc_policy.label == 972 dst1->aio_dstpolicy->pc_policy.label && 973 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 974 dst2->aio_srcpolicy->pc_policy.label != 975 dst2->aio_dstpolicy->pc_policy.label)) { 976 return(-1); 977 } 978 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 979 dst2->aio_srcpolicy->pc_policy.label == 980 dst2->aio_dstpolicy->pc_policy.label && 981 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 982 dst1->aio_srcpolicy->pc_policy.label != 983 dst1->aio_dstpolicy->pc_policy.label)) { 984 return(1); 985 } 986#endif 987 988 /* Rule 6: Prefer higher precedence. */ 989#ifdef INET6 990 if (dst1->aio_dstpolicy && 991 (dst2->aio_dstpolicy == NULL || 992 dst1->aio_dstpolicy->pc_policy.preced > 993 dst2->aio_dstpolicy->pc_policy.preced)) { 994 return(-1); 995 } 996 if (dst2->aio_dstpolicy && 997 (dst1->aio_dstpolicy == NULL || 998 dst2->aio_dstpolicy->pc_policy.preced > 999 dst1->aio_dstpolicy->pc_policy.preced)) { 1000 return(1); 1001 } 1002#endif 1003 1004 /* Rule 7: Prefer native transport. */ 1005 /* XXX: not implemented yet */ 1006 1007 /* Rule 8: Prefer smaller scope. */ 1008 if (dst1->aio_dstscope >= 0 && 1009 dst1->aio_dstscope < dst2->aio_dstscope) { 1010 return(-1); 1011 } 1012 if (dst2->aio_dstscope >= 0 && 1013 dst2->aio_dstscope < dst1->aio_dstscope) { 1014 return(1); 1015 } 1016 1017 /* 1018 * Rule 9: Use longest matching prefix. 1019 * We compare the match length in a same AF only. 1020 */ 1021 if (dst1->aio_ai->ai_addr->sa_family == 1022 dst2->aio_ai->ai_addr->sa_family) { 1023 if (dst1->aio_matchlen > dst2->aio_matchlen) { 1024 return(-1); 1025 } 1026 if (dst1->aio_matchlen < dst2->aio_matchlen) { 1027 return(1); 1028 } 1029 } 1030 1031 /* Rule 10: Otherwise, leave the order unchanged. */ 1032 return(-1); 1033} 1034 1035/* 1036 * Copy from scope.c. 1037 * XXX: we should standardize the functions and link them as standard 1038 * library. 1039 */ 1040static int 1041gai_addr2scopetype(sa) 1042 struct sockaddr *sa; 1043{ 1044#ifdef INET6 1045 struct sockaddr_in6 *sa6; 1046#endif 1047 struct sockaddr_in *sa4; 1048 1049 switch(sa->sa_family) { 1050#ifdef INET6 1051 case AF_INET6: 1052 sa6 = (struct sockaddr_in6 *)sa; 1053 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1054 /* just use the scope field of the multicast address */ 1055 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1056 } 1057 /* 1058 * Unicast addresses: map scope type to corresponding scope 1059 * value defined for multcast addresses. 1060 * XXX: hardcoded scope type values are bad... 1061 */ 1062 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1063 return(1); /* node local scope */ 1064 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1065 return(2); /* link-local scope */ 1066 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1067 return(5); /* site-local scope */ 1068 return(14); /* global scope */ 1069 break; 1070#endif 1071 case AF_INET: 1072 /* 1073 * IPv4 pseudo scoping according to RFC 3484. 1074 */ 1075 sa4 = (struct sockaddr_in *)sa; 1076 /* IPv4 autoconfiguration addresses have link-local scope. */ 1077 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1078 ((u_char *)&sa4->sin_addr)[1] == 254) 1079 return(2); 1080 /* Private addresses have site-local scope. */ 1081 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1082 (((u_char *)&sa4->sin_addr)[0] == 172 && 1083 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1084 (((u_char *)&sa4->sin_addr)[0] == 192 && 1085 ((u_char *)&sa4->sin_addr)[1] == 168)) 1086 return(14); /* XXX: It should be 5 unless NAT */ 1087 /* Loopback addresses have link-local scope. */ 1088 if (((u_char *)&sa4->sin_addr)[0] == 127) 1089 return(2); 1090 return(14); 1091 break; 1092 default: 1093 errno = EAFNOSUPPORT; /* is this a good error? */ 1094 return(-1); 1095 } 1096} 1097 1098/* 1099 * hostname == NULL. 1100 * passive socket -> anyaddr (0.0.0.0 or ::) 1101 * non-passive socket -> localhost (127.0.0.1 or ::1) 1102 */ 1103static int 1104explore_null(pai, servname, res) 1105 const struct addrinfo *pai; 1106 const char *servname; 1107 struct addrinfo **res; 1108{ 1109 int s; 1110 const struct afd *afd; 1111 struct addrinfo *cur; 1112 struct addrinfo sentinel; 1113 int error; 1114 1115 *res = NULL; 1116 sentinel.ai_next = NULL; 1117 cur = &sentinel; 1118 1119 /* 1120 * filter out AFs that are not supported by the kernel 1121 * XXX errno? 1122 */ 1123 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1124 if (s < 0) { 1125 if (errno != EMFILE) 1126 return 0; 1127 } else 1128 _close(s); 1129 1130 /* 1131 * if the servname does not match socktype/protocol, ignore it. 1132 */ 1133 if (get_portmatch(pai, servname) != 0) 1134 return 0; 1135 1136 afd = find_afd(pai->ai_family); 1137 if (afd == NULL) 1138 return 0; 1139 1140 if (pai->ai_flags & AI_PASSIVE) { 1141 GET_AI(cur->ai_next, afd, afd->a_addrany); 1142 /* xxx meaningless? 1143 * GET_CANONNAME(cur->ai_next, "anyaddr"); 1144 */ 1145 GET_PORT(cur->ai_next, servname); 1146 } else { 1147 GET_AI(cur->ai_next, afd, afd->a_loopback); 1148 /* xxx meaningless? 1149 * GET_CANONNAME(cur->ai_next, "localhost"); 1150 */ 1151 GET_PORT(cur->ai_next, servname); 1152 } 1153 cur = cur->ai_next; 1154 1155 *res = sentinel.ai_next; 1156 return 0; 1157 1158free: 1159 if (sentinel.ai_next) 1160 freeaddrinfo(sentinel.ai_next); 1161 return error; 1162} 1163 1164/* 1165 * numeric hostname 1166 */ 1167static int 1168explore_numeric(pai, hostname, servname, res, canonname) 1169 const struct addrinfo *pai; 1170 const char *hostname; 1171 const char *servname; 1172 struct addrinfo **res; 1173 const char *canonname; 1174{ 1175 const struct afd *afd; 1176 struct addrinfo *cur; 1177 struct addrinfo sentinel; 1178 int error; 1179 char pton[PTON_MAX]; 1180 1181 *res = NULL; 1182 sentinel.ai_next = NULL; 1183 cur = &sentinel; 1184 1185 /* 1186 * if the servname does not match socktype/protocol, ignore it. 1187 */ 1188 if (get_portmatch(pai, servname) != 0) 1189 return 0; 1190 1191 afd = find_afd(pai->ai_family); 1192 if (afd == NULL) 1193 return 0; 1194 1195 switch (afd->a_af) { 1196#if 1 /*X/Open spec*/ 1197 case AF_INET: 1198 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 1199 if (pai->ai_family == afd->a_af || 1200 pai->ai_family == PF_UNSPEC /*?*/) { 1201 GET_AI(cur->ai_next, afd, pton); 1202 GET_PORT(cur->ai_next, servname); 1203 if ((pai->ai_flags & AI_CANONNAME)) { 1204 /* 1205 * Set the numeric address itself as 1206 * the canonical name, based on a 1207 * clarification in rfc3493. 1208 */ 1209 GET_CANONNAME(cur->ai_next, canonname); 1210 } 1211 while (cur && cur->ai_next) 1212 cur = cur->ai_next; 1213 } else 1214 ERR(EAI_FAMILY); /*xxx*/ 1215 } 1216 break; 1217#endif 1218 default: 1219 if (inet_pton(afd->a_af, hostname, pton) == 1) { 1220 if (pai->ai_family == afd->a_af || 1221 pai->ai_family == PF_UNSPEC /*?*/) { 1222 GET_AI(cur->ai_next, afd, pton); 1223 GET_PORT(cur->ai_next, servname); 1224 if ((pai->ai_flags & AI_CANONNAME)) { 1225 /* 1226 * Set the numeric address itself as 1227 * the canonical name, based on a 1228 * clarification in rfc3493. 1229 */ 1230 GET_CANONNAME(cur->ai_next, canonname); 1231 } 1232 while (cur && cur->ai_next) 1233 cur = cur->ai_next; 1234 } else 1235 ERR(EAI_FAMILY); /* XXX */ 1236 } 1237 break; 1238 } 1239 1240 *res = sentinel.ai_next; 1241 return 0; 1242 1243free: 1244bad: 1245 if (sentinel.ai_next) 1246 freeaddrinfo(sentinel.ai_next); 1247 return error; 1248} 1249 1250/* 1251 * numeric hostname with scope 1252 */ 1253static int 1254explore_numeric_scope(pai, hostname, servname, res) 1255 const struct addrinfo *pai; 1256 const char *hostname; 1257 const char *servname; 1258 struct addrinfo **res; 1259{ 1260#if !defined(SCOPE_DELIMITER) || !defined(INET6) 1261 return explore_numeric(pai, hostname, servname, res, hostname); 1262#else 1263 const struct afd *afd; 1264 struct addrinfo *cur; 1265 int error; 1266 char *cp, *hostname2 = NULL, *scope, *addr; 1267 struct sockaddr_in6 *sin6; 1268 1269 /* 1270 * if the servname does not match socktype/protocol, ignore it. 1271 */ 1272 if (get_portmatch(pai, servname) != 0) 1273 return 0; 1274 1275 afd = find_afd(pai->ai_family); 1276 if (afd == NULL) 1277 return 0; 1278 1279 if (!afd->a_scoped) 1280 return explore_numeric(pai, hostname, servname, res, hostname); 1281 1282 cp = strchr(hostname, SCOPE_DELIMITER); 1283 if (cp == NULL) 1284 return explore_numeric(pai, hostname, servname, res, hostname); 1285 1286 /* 1287 * Handle special case of <scoped_address><delimiter><scope id> 1288 */ 1289 hostname2 = strdup(hostname); 1290 if (hostname2 == NULL) 1291 return EAI_MEMORY; 1292 /* terminate at the delimiter */ 1293 hostname2[cp - hostname] = '\0'; 1294 addr = hostname2; 1295 scope = cp + 1; 1296 1297 error = explore_numeric(pai, addr, servname, res, hostname); 1298 if (error == 0) { 1299 u_int32_t scopeid; 1300 1301 for (cur = *res; cur; cur = cur->ai_next) { 1302 if (cur->ai_family != AF_INET6) 1303 continue; 1304 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1305 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1306 free(hostname2); 1307 return(EAI_NONAME); /* XXX: is return OK? */ 1308 } 1309 sin6->sin6_scope_id = scopeid; 1310 } 1311 } 1312 1313 free(hostname2); 1314 1315 return error; 1316#endif 1317} 1318 1319static int 1320get_canonname(pai, ai, str) 1321 const struct addrinfo *pai; 1322 struct addrinfo *ai; 1323 const char *str; 1324{ 1325 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1326 ai->ai_canonname = strdup(str); 1327 if (ai->ai_canonname == NULL) 1328 return EAI_MEMORY; 1329 } 1330 return 0; 1331} 1332 1333static struct addrinfo * 1334get_ai(pai, afd, addr) 1335 const struct addrinfo *pai; 1336 const struct afd *afd; 1337 const char *addr; 1338{ 1339 char *p; 1340 struct addrinfo *ai; 1341#ifdef FAITH 1342 struct in6_addr faith_prefix; 1343 char *fp_str; 1344 int translate = 0; 1345#endif 1346 1347#ifdef FAITH 1348 /* 1349 * Transfrom an IPv4 addr into a special IPv6 addr format for 1350 * IPv6->IPv4 translation gateway. (only TCP is supported now) 1351 * 1352 * +-----------------------------------+------------+ 1353 * | faith prefix part (12 bytes) | embedded | 1354 * | | IPv4 addr part (4 bytes) 1355 * +-----------------------------------+------------+ 1356 * 1357 * faith prefix part is specified as ascii IPv6 addr format 1358 * in environmental variable GAI. 1359 * For FAITH to work correctly, routing to faith prefix must be 1360 * setup toward a machine where a FAITH daemon operates. 1361 * Also, the machine must enable some mechanizm 1362 * (e.g. faith interface hack) to divert those packet with 1363 * faith prefixed destination addr to user-land FAITH daemon. 1364 */ 1365 fp_str = getenv("GAI"); 1366 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && 1367 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { 1368 u_int32_t v4a; 1369 u_int8_t v4a_top; 1370 1371 memcpy(&v4a, addr, sizeof v4a); 1372 v4a_top = v4a >> IN_CLASSA_NSHIFT; 1373 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && 1374 v4a_top != 0 && v4a != IN_LOOPBACKNET) { 1375 afd = &afdl[N_INET6]; 1376 memcpy(&faith_prefix.s6_addr[12], addr, 1377 sizeof(struct in_addr)); 1378 translate = 1; 1379 } 1380 } 1381#endif 1382 1383 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 1384 + (afd->a_socklen)); 1385 if (ai == NULL) 1386 return NULL; 1387 1388 memcpy(ai, pai, sizeof(struct addrinfo)); 1389 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); 1390 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 1391 ai->ai_addr->sa_len = afd->a_socklen; 1392 ai->ai_addrlen = afd->a_socklen; 1393 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 1394 p = (char *)(void *)(ai->ai_addr); 1395#ifdef FAITH 1396 if (translate == 1) 1397 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); 1398 else 1399#endif 1400 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 1401 return ai; 1402} 1403 1404static int 1405get_portmatch(ai, servname) 1406 const struct addrinfo *ai; 1407 const char *servname; 1408{ 1409 1410 /* get_port does not touch first argument when matchonly == 1. */ 1411 /* LINTED const cast */ 1412 return get_port((struct addrinfo *)ai, servname, 1); 1413} 1414 1415static int 1416get_port(ai, servname, matchonly) 1417 struct addrinfo *ai; 1418 const char *servname; 1419 int matchonly; 1420{ 1421 const char *proto; 1422 struct servent *sp; 1423 int port; 1424 int allownumeric; 1425 1426 if (servname == NULL) 1427 return 0; 1428 switch (ai->ai_family) { 1429 case AF_INET: 1430#ifdef AF_INET6 1431 case AF_INET6: 1432#endif 1433 break; 1434 default: 1435 return 0; 1436 } 1437 1438 switch (ai->ai_socktype) { 1439 case SOCK_RAW: 1440 return EAI_SERVICE; 1441 case SOCK_DGRAM: 1442 case SOCK_STREAM: 1443 allownumeric = 1; 1444 break; 1445 case ANY: 1446 allownumeric = 0; 1447 break; 1448 default: 1449 return EAI_SOCKTYPE; 1450 } 1451 1452 port = str2number(servname); 1453 if (port >= 0) { 1454 if (!allownumeric) 1455 return EAI_SERVICE; 1456 if (port < 0 || port > 65535) 1457 return EAI_SERVICE; 1458 port = htons(port); 1459 } else { 1460 if (ai->ai_flags & AI_NUMERICSERV) 1461 return EAI_NONAME; 1462 switch (ai->ai_socktype) { 1463 case SOCK_DGRAM: 1464 proto = "udp"; 1465 break; 1466 case SOCK_STREAM: 1467 proto = "tcp"; 1468 break; 1469 default: 1470 proto = NULL; 1471 break; 1472 } 1473 1474 THREAD_LOCK(); 1475 if ((sp = getservbyname(servname, proto)) == NULL) { 1476 THREAD_UNLOCK(); 1477 return EAI_SERVICE; 1478 } 1479 port = sp->s_port; 1480 THREAD_UNLOCK(); 1481 } 1482 1483 if (!matchonly) { 1484 switch (ai->ai_family) { 1485 case AF_INET: 1486 ((struct sockaddr_in *)(void *) 1487 ai->ai_addr)->sin_port = port; 1488 break; 1489#ifdef INET6 1490 case AF_INET6: 1491 ((struct sockaddr_in6 *)(void *) 1492 ai->ai_addr)->sin6_port = port; 1493 break; 1494#endif 1495 } 1496 } 1497 1498 return 0; 1499} 1500 1501static const struct afd * 1502find_afd(af) 1503 int af; 1504{ 1505 const struct afd *afd; 1506 1507 if (af == PF_UNSPEC) 1508 return NULL; 1509 for (afd = afdl; afd->a_af; afd++) { 1510 if (afd->a_af == af) 1511 return afd; 1512 } 1513 return NULL; 1514} 1515 1516/* 1517 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1518 * will take care of it. 1519 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1520 * if the code is right or not. 1521 * 1522 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1523 * _dns_getaddrinfo. 1524 */ 1525static int 1526addrconfig(pai) 1527 struct addrinfo *pai; 1528{ 1529 int s, af; 1530 1531 /* 1532 * TODO: 1533 * Note that implementation dependent test for address 1534 * configuration should be done everytime called 1535 * (or apropriate interval), 1536 * because addresses will be dynamically assigned or deleted. 1537 */ 1538 af = pai->ai_family; 1539 if (af == AF_UNSPEC) { 1540 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1541 af = AF_INET; 1542 else { 1543 _close(s); 1544 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1545 af = AF_INET6; 1546 else 1547 _close(s); 1548 } 1549 } 1550 if (af != AF_UNSPEC) { 1551 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1552 return 0; 1553 _close(s); 1554 } 1555 pai->ai_family = af; 1556 return 1; 1557} 1558 1559#ifdef INET6 1560/* convert a string to a scope identifier. XXX: IPv6 specific */ 1561static int 1562ip6_str2scopeid(scope, sin6, scopeid) 1563 char *scope; 1564 struct sockaddr_in6 *sin6; 1565 u_int32_t *scopeid; 1566{ 1567 u_long lscopeid; 1568 struct in6_addr *a6; 1569 char *ep; 1570 1571 a6 = &sin6->sin6_addr; 1572 1573 /* empty scopeid portion is invalid */ 1574 if (*scope == '\0') 1575 return -1; 1576 1577 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1578 /* 1579 * We currently assume a one-to-one mapping between links 1580 * and interfaces, so we simply use interface indices for 1581 * like-local scopes. 1582 */ 1583 *scopeid = if_nametoindex(scope); 1584 if (*scopeid == 0) 1585 goto trynumeric; 1586 return 0; 1587 } 1588 1589 /* still unclear about literal, allow numeric only - placeholder */ 1590 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1591 goto trynumeric; 1592 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1593 goto trynumeric; 1594 else 1595 goto trynumeric; /* global */ 1596 1597 /* try to convert to a numeric id as a last resort */ 1598 trynumeric: 1599 errno = 0; 1600 lscopeid = strtoul(scope, &ep, 10); 1601 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1602 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1603 return 0; 1604 else 1605 return -1; 1606} 1607#endif 1608 1609/* 1610 * FQDN hostname, DNS lookup 1611 */ 1612static int 1613explore_fqdn(pai, hostname, servname, res) 1614 const struct addrinfo *pai; 1615 const char *hostname; 1616 const char *servname; 1617 struct addrinfo **res; 1618{ 1619 struct addrinfo *result; 1620 struct addrinfo *cur; 1621 int error = 0; 1622 static const ns_dtab dtab[] = { 1623 NS_FILES_CB(_files_getaddrinfo, NULL) 1624 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1625 NS_NIS_CB(_yp_getaddrinfo, NULL) 1626 { 0 } 1627 }; 1628 1629 result = NULL; 1630 1631 /* 1632 * if the servname does not match socktype/protocol, ignore it. 1633 */ 1634 if (get_portmatch(pai, servname) != 0) 1635 return 0; 1636 1637 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1638 default_dns_files, hostname, pai)) { 1639 case NS_TRYAGAIN: 1640 error = EAI_AGAIN; 1641 goto free; 1642 case NS_UNAVAIL: 1643 error = EAI_FAIL; 1644 goto free; 1645 case NS_NOTFOUND: 1646 error = EAI_NONAME; 1647 goto free; 1648 case NS_SUCCESS: 1649 error = 0; 1650 for (cur = result; cur; cur = cur->ai_next) { 1651 GET_PORT(cur, servname); 1652 /* canonname should be filled already */ 1653 } 1654 break; 1655 } 1656 1657 *res = result; 1658 1659 return 0; 1660 1661free: 1662 if (result) 1663 freeaddrinfo(result); 1664 return error; 1665} 1666 1667#ifdef DEBUG 1668static const char AskedForGot[] = 1669 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1670#endif 1671static FILE *hostf = NULL; 1672 1673static struct addrinfo * 1674getanswer(answer, anslen, qname, qtype, pai) 1675 const querybuf *answer; 1676 int anslen; 1677 const char *qname; 1678 int qtype; 1679 const struct addrinfo *pai; 1680{ 1681 struct addrinfo sentinel, *cur; 1682 struct addrinfo ai; 1683 const struct afd *afd; 1684 char *canonname; 1685 const HEADER *hp; 1686 const u_char *cp; 1687 int n; 1688 const u_char *eom; 1689 char *bp, *ep; 1690 int type, class, ancount, qdcount; 1691 int haveanswer, had_error; 1692 char tbuf[MAXDNAME]; 1693 int (*name_ok)(const char *); 1694 char hostbuf[8*1024]; 1695 1696 memset(&sentinel, 0, sizeof(sentinel)); 1697 cur = &sentinel; 1698 1699 canonname = NULL; 1700 eom = answer->buf + anslen; 1701 switch (qtype) { 1702 case T_A: 1703 case T_AAAA: 1704 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1705 name_ok = res_hnok; 1706 break; 1707 default: 1708 return (NULL); /* XXX should be abort(); */ 1709 } 1710 /* 1711 * find first satisfactory answer 1712 */ 1713 hp = &answer->hdr; 1714 ancount = ntohs(hp->ancount); 1715 qdcount = ntohs(hp->qdcount); 1716 bp = hostbuf; 1717 ep = hostbuf + sizeof hostbuf; 1718 cp = answer->buf + HFIXEDSZ; 1719 if (qdcount != 1) { 1720 h_errno = NO_RECOVERY; 1721 return (NULL); 1722 } 1723 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1724 if ((n < 0) || !(*name_ok)(bp)) { 1725 h_errno = NO_RECOVERY; 1726 return (NULL); 1727 } 1728 cp += n + QFIXEDSZ; 1729 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1730 /* res_send() has already verified that the query name is the 1731 * same as the one we sent; this just gets the expanded name 1732 * (i.e., with the succeeding search-domain tacked on). 1733 */ 1734 n = strlen(bp) + 1; /* for the \0 */ 1735 if (n >= MAXHOSTNAMELEN) { 1736 h_errno = NO_RECOVERY; 1737 return (NULL); 1738 } 1739 canonname = bp; 1740 bp += n; 1741 /* The qname can be abbreviated, but h_name is now absolute. */ 1742 qname = canonname; 1743 } 1744 haveanswer = 0; 1745 had_error = 0; 1746 while (ancount-- > 0 && cp < eom && !had_error) { 1747 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1748 if ((n < 0) || !(*name_ok)(bp)) { 1749 had_error++; 1750 continue; 1751 } 1752 cp += n; /* name */ 1753 type = _getshort(cp); 1754 cp += INT16SZ; /* type */ 1755 class = _getshort(cp); 1756 cp += INT16SZ + INT32SZ; /* class, TTL */ 1757 n = _getshort(cp); 1758 cp += INT16SZ; /* len */ 1759 if (class != C_IN) { 1760 /* XXX - debug? syslog? */ 1761 cp += n; 1762 continue; /* XXX - had_error++ ? */ 1763 } 1764 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1765 type == T_CNAME) { 1766 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1767 if ((n < 0) || !(*name_ok)(tbuf)) { 1768 had_error++; 1769 continue; 1770 } 1771 cp += n; 1772 /* Get canonical name. */ 1773 n = strlen(tbuf) + 1; /* for the \0 */ 1774 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1775 had_error++; 1776 continue; 1777 } 1778 strlcpy(bp, tbuf, ep - bp); 1779 canonname = bp; 1780 bp += n; 1781 continue; 1782 } 1783 if (qtype == T_ANY) { 1784 if (!(type == T_A || type == T_AAAA)) { 1785 cp += n; 1786 continue; 1787 } 1788 } else if (type != qtype) { 1789#ifdef DEBUG 1790 if (type != T_KEY && type != T_SIG) 1791 syslog(LOG_NOTICE|LOG_AUTH, 1792 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1793 qname, p_class(C_IN), p_type(qtype), 1794 p_type(type)); 1795#endif 1796 cp += n; 1797 continue; /* XXX - had_error++ ? */ 1798 } 1799 switch (type) { 1800 case T_A: 1801 case T_AAAA: 1802 if (strcasecmp(canonname, bp) != 0) { 1803#ifdef DEBUG 1804 syslog(LOG_NOTICE|LOG_AUTH, 1805 AskedForGot, canonname, bp); 1806#endif 1807 cp += n; 1808 continue; /* XXX - had_error++ ? */ 1809 } 1810 if (type == T_A && n != INADDRSZ) { 1811 cp += n; 1812 continue; 1813 } 1814 if (type == T_AAAA && n != IN6ADDRSZ) { 1815 cp += n; 1816 continue; 1817 } 1818#ifdef FILTER_V4MAPPED 1819 if (type == T_AAAA) { 1820 struct in6_addr in6; 1821 memcpy(&in6, cp, sizeof(in6)); 1822 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1823 cp += n; 1824 continue; 1825 } 1826 } 1827#endif 1828 if (!haveanswer) { 1829 int nn; 1830 1831 canonname = bp; 1832 nn = strlen(bp) + 1; /* for the \0 */ 1833 bp += nn; 1834 } 1835 1836 /* don't overwrite pai */ 1837 ai = *pai; 1838 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1839 afd = find_afd(ai.ai_family); 1840 if (afd == NULL) { 1841 cp += n; 1842 continue; 1843 } 1844 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1845 if (cur->ai_next == NULL) 1846 had_error++; 1847 while (cur && cur->ai_next) 1848 cur = cur->ai_next; 1849 cp += n; 1850 break; 1851 default: 1852 abort(); 1853 } 1854 if (!had_error) 1855 haveanswer++; 1856 } 1857 if (haveanswer) { 1858#if defined(RESOLVSORT) 1859 /* 1860 * We support only IPv4 address for backward 1861 * compatibility against gethostbyname(3). 1862 */ 1863 if (_res.nsort && qtype == T_A) { 1864 if (addr4sort(&sentinel) < 0) { 1865 freeaddrinfo(sentinel.ai_next); 1866 h_errno = NO_RECOVERY; 1867 return NULL; 1868 } 1869 } 1870#endif /*RESOLVSORT*/ 1871 if (!canonname) 1872 (void)get_canonname(pai, sentinel.ai_next, qname); 1873 else 1874 (void)get_canonname(pai, sentinel.ai_next, canonname); 1875 h_errno = NETDB_SUCCESS; 1876 return sentinel.ai_next; 1877 } 1878 1879 h_errno = NO_RECOVERY; 1880 return NULL; 1881} 1882 1883#ifdef RESOLVSORT 1884struct addr_ptr { 1885 struct addrinfo *ai; 1886 int aval; 1887}; 1888 1889static int 1890addr4sort(struct addrinfo *sentinel) 1891{ 1892 struct addrinfo *ai; 1893 struct addr_ptr *addrs, addr; 1894 struct sockaddr_in *sin; 1895 int naddrs, i, j; 1896 int needsort = 0; 1897 1898 if (!sentinel) 1899 return -1; 1900 naddrs = 0; 1901 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1902 naddrs++; 1903 if (naddrs < 2) 1904 return 0; /* We don't need sorting. */ 1905 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1906 return -1; 1907 i = 0; 1908 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1909 sin = (struct sockaddr_in *)ai->ai_addr; 1910 for (j = 0; (unsigned)j < _res.nsort; j++) { 1911 if (_res.sort_list[j].addr.s_addr == 1912 (sin->sin_addr.s_addr & _res.sort_list[j].mask)) 1913 break; 1914 } 1915 addrs[i].ai = ai; 1916 addrs[i].aval = j; 1917 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1918 needsort = i; 1919 i++; 1920 } 1921 if (!needsort) { 1922 free(addrs); 1923 return 0; 1924 } 1925 1926 while (needsort < naddrs) { 1927 for (j = needsort - 1; j >= 0; j--) { 1928 if (addrs[j].aval > addrs[j+1].aval) { 1929 addr = addrs[j]; 1930 addrs[j] = addrs[j + 1]; 1931 addrs[j + 1] = addr; 1932 } else 1933 break; 1934 } 1935 needsort++; 1936 } 1937 1938 ai = sentinel; 1939 for (i = 0; i < naddrs; ++i) { 1940 ai->ai_next = addrs[i].ai; 1941 ai = ai->ai_next; 1942 } 1943 ai->ai_next = NULL; 1944 free(addrs); 1945 return 0; 1946} 1947#endif /*RESOLVSORT*/ 1948 1949/*ARGSUSED*/ 1950static int 1951_dns_getaddrinfo(rv, cb_data, ap) 1952 void *rv; 1953 void *cb_data; 1954 va_list ap; 1955{ 1956 struct addrinfo *ai; 1957 querybuf *buf, *buf2; 1958 const char *hostname; 1959 const struct addrinfo *pai; 1960 struct addrinfo sentinel, *cur; 1961 struct res_target q, q2; 1962 1963 hostname = va_arg(ap, char *); 1964 pai = va_arg(ap, const struct addrinfo *); 1965 1966 memset(&q, 0, sizeof(q2)); 1967 memset(&q2, 0, sizeof(q2)); 1968 memset(&sentinel, 0, sizeof(sentinel)); 1969 cur = &sentinel; 1970 1971 buf = malloc(sizeof(*buf)); 1972 if (!buf) { 1973 h_errno = NETDB_INTERNAL; 1974 return NS_NOTFOUND; 1975 } 1976 buf2 = malloc(sizeof(*buf2)); 1977 if (!buf2) { 1978 free(buf); 1979 h_errno = NETDB_INTERNAL; 1980 return NS_NOTFOUND; 1981 } 1982 1983 switch (pai->ai_family) { 1984 case AF_UNSPEC: 1985 q.name = hostname; 1986 q.qclass = C_IN; 1987 q.qtype = T_A; 1988 q.answer = buf->buf; 1989 q.anslen = sizeof(buf->buf); 1990 q.next = &q2; 1991 q2.name = hostname; 1992 q2.qclass = C_IN; 1993 q2.qtype = T_AAAA; 1994 q2.answer = buf2->buf; 1995 q2.anslen = sizeof(buf2->buf); 1996 break; 1997 case AF_INET: 1998 q.name = hostname; 1999 q.qclass = C_IN; 2000 q.qtype = T_A; 2001 q.answer = buf->buf; 2002 q.anslen = sizeof(buf->buf); 2003 break; 2004 case AF_INET6: 2005 q.name = hostname; 2006 q.qclass = C_IN; 2007 q.qtype = T_AAAA; 2008 q.answer = buf->buf; 2009 q.anslen = sizeof(buf->buf); 2010 break; 2011 default: 2012 free(buf); 2013 free(buf2); 2014 return NS_UNAVAIL; 2015 } 2016 if (res_searchN(hostname, &q) < 0) { 2017 free(buf); 2018 free(buf2); 2019 return NS_NOTFOUND; 2020 } 2021 /* prefer IPv6 */ 2022 if (q.next) { 2023 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai); 2024 if (ai) { 2025 cur->ai_next = ai; 2026 while (cur && cur->ai_next) 2027 cur = cur->ai_next; 2028 } 2029 } 2030 ai = getanswer(buf, q.n, q.name, q.qtype, pai); 2031 if (ai) 2032 cur->ai_next = ai; 2033 free(buf); 2034 free(buf2); 2035 if (sentinel.ai_next == NULL) 2036 switch (h_errno) { 2037 case HOST_NOT_FOUND: 2038 return NS_NOTFOUND; 2039 case TRY_AGAIN: 2040 return NS_TRYAGAIN; 2041 default: 2042 return NS_UNAVAIL; 2043 } 2044 *((struct addrinfo **)rv) = sentinel.ai_next; 2045 return NS_SUCCESS; 2046} 2047 2048static void 2049_sethtent() 2050{ 2051 if (!hostf) 2052 hostf = fopen(_PATH_HOSTS, "r" ); 2053 else 2054 rewind(hostf); 2055} 2056 2057static void 2058_endhtent() 2059{ 2060 if (hostf) { 2061 (void) fclose(hostf); 2062 hostf = NULL; 2063 } 2064} 2065 2066static struct addrinfo * 2067_gethtent(name, pai) 2068 const char *name; 2069 const struct addrinfo *pai; 2070{ 2071 char *p; 2072 char *cp, *tname, *cname; 2073 struct addrinfo hints, *res0, *res; 2074 int error; 2075 const char *addr; 2076 char hostbuf[8*1024]; 2077 2078 if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) 2079 return (NULL); 2080again: 2081 if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) 2082 return (NULL); 2083 if (*p == '#') 2084 goto again; 2085 cp = strpbrk(p, "#\n"); 2086 if (cp != NULL) 2087 *cp = '\0'; 2088 if (!(cp = strpbrk(p, " \t"))) 2089 goto again; 2090 *cp++ = '\0'; 2091 addr = p; 2092 cname = NULL; 2093 /* if this is not something we're looking for, skip it. */ 2094 while (cp && *cp) { 2095 if (*cp == ' ' || *cp == '\t') { 2096 cp++; 2097 continue; 2098 } 2099 tname = cp; 2100 if (cname == NULL) 2101 cname = cp; 2102 if ((cp = strpbrk(cp, " \t")) != NULL) 2103 *cp++ = '\0'; 2104 if (strcasecmp(name, tname) == 0) 2105 goto found; 2106 } 2107 goto again; 2108 2109found: 2110 /* we should not glob socktype/protocol here */ 2111 memset(&hints, 0, sizeof(hints)); 2112 hints.ai_family = pai->ai_family; 2113 hints.ai_socktype = SOCK_DGRAM; 2114 hints.ai_protocol = 0; 2115 hints.ai_flags = AI_NUMERICHOST; 2116 error = getaddrinfo(addr, "0", &hints, &res0); 2117 if (error) 2118 goto again; 2119#ifdef FILTER_V4MAPPED 2120 /* XXX should check all items in the chain */ 2121 if (res0->ai_family == AF_INET6 && 2122 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2123 freeaddrinfo(res0); 2124 goto again; 2125 } 2126#endif 2127 for (res = res0; res; res = res->ai_next) { 2128 /* cover it up */ 2129 res->ai_flags = pai->ai_flags; 2130 res->ai_socktype = pai->ai_socktype; 2131 res->ai_protocol = pai->ai_protocol; 2132 2133 if (pai->ai_flags & AI_CANONNAME) { 2134 if (get_canonname(pai, res, cname) != 0) { 2135 freeaddrinfo(res0); 2136 goto again; 2137 } 2138 } 2139 } 2140 return res0; 2141} 2142 2143/*ARGSUSED*/ 2144static int 2145_files_getaddrinfo(rv, cb_data, ap) 2146 void *rv; 2147 void *cb_data; 2148 va_list ap; 2149{ 2150 const char *name; 2151 const struct addrinfo *pai; 2152 struct addrinfo sentinel, *cur; 2153 struct addrinfo *p; 2154 2155 name = va_arg(ap, char *); 2156 pai = va_arg(ap, struct addrinfo *); 2157 2158 memset(&sentinel, 0, sizeof(sentinel)); 2159 cur = &sentinel; 2160 2161 THREAD_LOCK(); 2162 _sethtent(); 2163 while ((p = _gethtent(name, pai)) != NULL) { 2164 cur->ai_next = p; 2165 while (cur && cur->ai_next) 2166 cur = cur->ai_next; 2167 } 2168 _endhtent(); 2169 THREAD_UNLOCK(); 2170 2171 *((struct addrinfo **)rv) = sentinel.ai_next; 2172 if (sentinel.ai_next == NULL) 2173 return NS_NOTFOUND; 2174 return NS_SUCCESS; 2175} 2176 2177#ifdef YP 2178static char *__ypdomain; 2179 2180/*ARGSUSED*/ 2181static struct addrinfo * 2182_yphostent(line, pai) 2183 char *line; 2184 const struct addrinfo *pai; 2185{ 2186 struct addrinfo sentinel, *cur; 2187 struct addrinfo hints, *res, *res0; 2188 int error; 2189 char *p = line; 2190 const char *addr, *canonname; 2191 char *nextline; 2192 char *cp; 2193 2194 addr = canonname = NULL; 2195 2196 memset(&sentinel, 0, sizeof(sentinel)); 2197 cur = &sentinel; 2198 2199nextline: 2200 /* terminate line */ 2201 cp = strchr(p, '\n'); 2202 if (cp) { 2203 *cp++ = '\0'; 2204 nextline = cp; 2205 } else 2206 nextline = NULL; 2207 2208 cp = strpbrk(p, " \t"); 2209 if (cp == NULL) { 2210 if (canonname == NULL) 2211 return (NULL); 2212 else 2213 goto done; 2214 } 2215 *cp++ = '\0'; 2216 2217 addr = p; 2218 2219 while (cp && *cp) { 2220 if (*cp == ' ' || *cp == '\t') { 2221 cp++; 2222 continue; 2223 } 2224 if (!canonname) 2225 canonname = cp; 2226 if ((cp = strpbrk(cp, " \t")) != NULL) 2227 *cp++ = '\0'; 2228 } 2229 2230 hints = *pai; 2231 hints.ai_flags = AI_NUMERICHOST; 2232 error = getaddrinfo(addr, NULL, &hints, &res0); 2233 if (error == 0) { 2234 for (res = res0; res; res = res->ai_next) { 2235 /* cover it up */ 2236 res->ai_flags = pai->ai_flags; 2237 2238 if (pai->ai_flags & AI_CANONNAME) 2239 (void)get_canonname(pai, res, canonname); 2240 } 2241 } else 2242 res0 = NULL; 2243 if (res0) { 2244 cur->ai_next = res0; 2245 while (cur && cur->ai_next) 2246 cur = cur->ai_next; 2247 } 2248 2249 if (nextline) { 2250 p = nextline; 2251 goto nextline; 2252 } 2253 2254done: 2255 return sentinel.ai_next; 2256} 2257 2258/*ARGSUSED*/ 2259static int 2260_yp_getaddrinfo(rv, cb_data, ap) 2261 void *rv; 2262 void *cb_data; 2263 va_list ap; 2264{ 2265 struct addrinfo sentinel, *cur; 2266 struct addrinfo *ai = NULL; 2267 static char *__ypcurrent; 2268 int __ypcurrentlen, r; 2269 const char *name; 2270 const struct addrinfo *pai; 2271 2272 name = va_arg(ap, char *); 2273 pai = va_arg(ap, const struct addrinfo *); 2274 2275 memset(&sentinel, 0, sizeof(sentinel)); 2276 cur = &sentinel; 2277 2278 THREAD_LOCK(); 2279 if (!__ypdomain) { 2280 if (_yp_check(&__ypdomain) == 0) { 2281 THREAD_UNLOCK(); 2282 return NS_UNAVAIL; 2283 } 2284 } 2285 if (__ypcurrent) 2286 free(__ypcurrent); 2287 __ypcurrent = NULL; 2288 2289 /* hosts.byname is only for IPv4 (Solaris8) */ 2290 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2291 r = yp_match(__ypdomain, "hosts.byname", name, 2292 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 2293 if (r == 0) { 2294 struct addrinfo ai4; 2295 2296 ai4 = *pai; 2297 ai4.ai_family = AF_INET; 2298 ai = _yphostent(__ypcurrent, &ai4); 2299 if (ai) { 2300 cur->ai_next = ai; 2301 while (cur && cur->ai_next) 2302 cur = cur->ai_next; 2303 } 2304 } 2305 } 2306 2307 /* ipnodes.byname can hold both IPv4/v6 */ 2308 r = yp_match(__ypdomain, "ipnodes.byname", name, 2309 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 2310 if (r == 0) { 2311 ai = _yphostent(__ypcurrent, pai); 2312 if (ai) { 2313 cur->ai_next = ai; 2314 while (cur && cur->ai_next) 2315 cur = cur->ai_next; 2316 } 2317 } 2318 THREAD_UNLOCK(); 2319 2320 if (sentinel.ai_next == NULL) { 2321 h_errno = HOST_NOT_FOUND; 2322 return NS_NOTFOUND; 2323 } 2324 *((struct addrinfo **)rv) = sentinel.ai_next; 2325 return NS_SUCCESS; 2326} 2327#endif 2328 2329/* resolver logic */ 2330 2331extern const char *__hostalias(const char *); 2332 2333/* 2334 * Formulate a normal query, send, and await answer. 2335 * Returned answer is placed in supplied buffer "answer". 2336 * Perform preliminary check of answer, returning success only 2337 * if no error is indicated and the answer count is nonzero. 2338 * Return the size of the response on success, -1 on error. 2339 * Error number is left in h_errno. 2340 * 2341 * Caller must parse answer and determine whether it answers the question. 2342 */ 2343static int 2344res_queryN(name, target) 2345 const char *name; /* domain name */ 2346 struct res_target *target; 2347{ 2348 u_char *buf; 2349 HEADER *hp; 2350 int n; 2351 struct res_target *t; 2352 int rcode; 2353 int ancount; 2354 2355 rcode = NOERROR; 2356 ancount = 0; 2357 2358 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2359 h_errno = NETDB_INTERNAL; 2360 return (-1); 2361 } 2362 2363 buf = malloc(MAXPACKET); 2364 if (!buf) { 2365 h_errno = NETDB_INTERNAL; 2366 return -1; 2367 } 2368 2369 for (t = target; t; t = t->next) { 2370 int class, type; 2371 u_char *answer; 2372 int anslen; 2373 2374 hp = (HEADER *)(void *)t->answer; 2375 hp->rcode = NOERROR; /* default */ 2376 2377 /* make it easier... */ 2378 class = t->qclass; 2379 type = t->qtype; 2380 answer = t->answer; 2381 anslen = t->anslen; 2382#ifdef DEBUG 2383 if (_res.options & RES_DEBUG) 2384 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2385#endif 2386 2387 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, 2388 buf, MAXPACKET); 2389 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) 2390 n = res_opt(n, buf, MAXPACKET, anslen); 2391 if (n <= 0) { 2392#ifdef DEBUG 2393 if (_res.options & RES_DEBUG) 2394 printf(";; res_query: mkquery failed\n"); 2395#endif 2396 free(buf); 2397 h_errno = NO_RECOVERY; 2398 return (n); 2399 } 2400 n = res_send(buf, n, answer, anslen); 2401#if 0 2402 if (n < 0) { 2403#ifdef DEBUG 2404 if (_res.options & RES_DEBUG) 2405 printf(";; res_query: send error\n"); 2406#endif 2407 free(buf); 2408 h_errno = TRY_AGAIN; 2409 return (n); 2410 } 2411#endif 2412 2413 if (n < 0 || n > anslen) 2414 hp->rcode = FORMERR; /* XXX not very informative */ 2415 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2416 rcode = hp->rcode; /* record most recent error */ 2417#ifdef DEBUG 2418 if (_res.options & RES_DEBUG) 2419 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2420 ntohs(hp->ancount)); 2421#endif 2422 continue; 2423 } 2424 2425 ancount += ntohs(hp->ancount); 2426 2427 t->n = n; 2428 } 2429 2430 free(buf); 2431 2432 if (ancount == 0) { 2433 switch (rcode) { 2434 case NXDOMAIN: 2435 h_errno = HOST_NOT_FOUND; 2436 break; 2437 case SERVFAIL: 2438 h_errno = TRY_AGAIN; 2439 break; 2440 case NOERROR: 2441 h_errno = NO_DATA; 2442 break; 2443 case FORMERR: 2444 case NOTIMP: 2445 case REFUSED: 2446 default: 2447 h_errno = NO_RECOVERY; 2448 break; 2449 } 2450 return (-1); 2451 } 2452 return (ancount); 2453} 2454 2455/* 2456 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2457 * Return the size of the response on success, -1 on error. 2458 * If enabled, implement search rules until answer or unrecoverable failure 2459 * is detected. Error code, if any, is left in h_errno. 2460 */ 2461static int 2462res_searchN(name, target) 2463 const char *name; /* domain name */ 2464 struct res_target *target; 2465{ 2466 const char *cp, * const *domain; 2467 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2468 u_int dots; 2469 int trailing_dot, ret, saved_herrno; 2470 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 2471 2472 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2473 h_errno = NETDB_INTERNAL; 2474 return (-1); 2475 } 2476 2477 errno = 0; 2478 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 2479 dots = 0; 2480 for (cp = name; *cp; cp++) 2481 dots += (*cp == '.'); 2482 trailing_dot = 0; 2483 if (cp > name && *--cp == '.') 2484 trailing_dot++; 2485 2486 /* 2487 * if there aren't any dots, it could be a user-level alias 2488 */ 2489 if (!dots && (cp = __hostalias(name)) != NULL) 2490 return (res_queryN(cp, target)); 2491 2492 /* 2493 * If there are dots in the name already, let's just give it a try 2494 * 'as is'. The threshold can be set with the "ndots" option. 2495 */ 2496 saved_herrno = -1; 2497 if (dots >= _res.ndots) { 2498 ret = res_querydomainN(name, NULL, target); 2499 if (ret > 0) 2500 return (ret); 2501 saved_herrno = h_errno; 2502 tried_as_is++; 2503 } 2504 2505 /* 2506 * We do at least one level of search if 2507 * - there is no dot and RES_DEFNAME is set, or 2508 * - there is at least one dot, there is no trailing dot, 2509 * and RES_DNSRCH is set. 2510 */ 2511 if ((!dots && (_res.options & RES_DEFNAMES)) || 2512 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { 2513 int done = 0; 2514 2515 for (domain = (const char * const *)_res.dnsrch; 2516 *domain && !done; 2517 domain++) { 2518 2519 ret = res_querydomainN(name, *domain, target); 2520 if (ret > 0) 2521 return (ret); 2522 2523 /* 2524 * If no server present, give up. 2525 * If name isn't found in this domain, 2526 * keep trying higher domains in the search list 2527 * (if that's enabled). 2528 * On a NO_DATA error, keep trying, otherwise 2529 * a wildcard entry of another type could keep us 2530 * from finding this entry higher in the domain. 2531 * If we get some other error (negative answer or 2532 * server failure), then stop searching up, 2533 * but try the input name below in case it's 2534 * fully-qualified. 2535 */ 2536 if (errno == ECONNREFUSED) { 2537 h_errno = TRY_AGAIN; 2538 return (-1); 2539 } 2540 2541 switch (h_errno) { 2542 case NO_DATA: 2543 got_nodata++; 2544 /* FALLTHROUGH */ 2545 case HOST_NOT_FOUND: 2546 /* keep trying */ 2547 break; 2548 case TRY_AGAIN: 2549 if (hp->rcode == SERVFAIL) { 2550 /* try next search element, if any */ 2551 got_servfail++; 2552 break; 2553 } 2554 /* FALLTHROUGH */ 2555 default: 2556 /* anything else implies that we're done */ 2557 done++; 2558 } 2559 /* 2560 * if we got here for some reason other than DNSRCH, 2561 * we only wanted one iteration of the loop, so stop. 2562 */ 2563 if (!(_res.options & RES_DNSRCH)) 2564 done++; 2565 } 2566 } 2567 2568 /* 2569 * if we have not already tried the name "as is", do that now. 2570 * note that we do this regardless of how many dots were in the 2571 * name or whether it ends with a dot. 2572 */ 2573 if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) { 2574 ret = res_querydomainN(name, NULL, target); 2575 if (ret > 0) 2576 return (ret); 2577 } 2578 2579 /* 2580 * if we got here, we didn't satisfy the search. 2581 * if we did an initial full query, return that query's h_errno 2582 * (note that we wouldn't be here if that query had succeeded). 2583 * else if we ever got a nodata, send that back as the reason. 2584 * else send back meaningless h_errno, that being the one from 2585 * the last DNSRCH we did. 2586 */ 2587 if (saved_herrno != -1) 2588 h_errno = saved_herrno; 2589 else if (got_nodata) 2590 h_errno = NO_DATA; 2591 else if (got_servfail) 2592 h_errno = TRY_AGAIN; 2593 return (-1); 2594} 2595 2596/* 2597 * Perform a call on res_query on the concatenation of name and domain, 2598 * removing a trailing dot from name if domain is NULL. 2599 */ 2600static int 2601res_querydomainN(name, domain, target) 2602 const char *name, *domain; 2603 struct res_target *target; 2604{ 2605 char nbuf[MAXDNAME]; 2606 const char *longname = nbuf; 2607 size_t n, d; 2608 2609 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2610 h_errno = NETDB_INTERNAL; 2611 return (-1); 2612 } 2613#ifdef DEBUG 2614 if (_res.options & RES_DEBUG) 2615 printf(";; res_querydomain(%s, %s)\n", 2616 name, domain?domain:"<Nil>"); 2617#endif 2618 if (domain == NULL) { 2619 /* 2620 * Check for trailing '.'; 2621 * copy without '.' if present. 2622 */ 2623 n = strlen(name); 2624 if (n >= MAXDNAME) { 2625 h_errno = NO_RECOVERY; 2626 return (-1); 2627 } 2628 if (n > 0 && name[--n] == '.') { 2629 strncpy(nbuf, name, n); 2630 nbuf[n] = '\0'; 2631 } else 2632 longname = name; 2633 } else { 2634 n = strlen(name); 2635 d = strlen(domain); 2636 if (n + d + 1 >= MAXDNAME) { 2637 h_errno = NO_RECOVERY; 2638 return (-1); 2639 } 2640 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2641 } 2642 return (res_queryN(longname, target)); 2643} 2644