1 /* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * "#ifdef FAITH" part is local hack for supporting IPv4-v6 translator. 34 * 35 * Issues to be discussed: 36 * - Thread safe-ness must be checked. 37 * - Return values. There are nonstandard return values defined and used 38 * in the source code. This is because RFC2553 is silent about which error 39 * code must be returned for which situation. 40 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 41 * invalid. current code - SEGV on freeaddrinfo(NULL) 42 * 43 * Note: 44 * - The code filters out AFs that are not supported by the kernel, 45 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 46 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 47 * in ai_flags? 48 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 49 * (1) what should we do against numeric hostname (2) what should we do 50 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 51 * non-loopback address configured? global address configured? 52 * 53 * OS specific notes for netbsd/openbsd/freebsd4/bsdi4: 54 * - To avoid search order issue, we have a big amount of code duplicate 55 * from gethnamaddr.c and some other places. The issues that there's no 56 * lower layer function to lookup "IPv4 or IPv6" record. Calling 57 * gethostbyname2 from getaddrinfo will end up in wrong search order, as 58 * presented above. 59 * 60 * OS specific notes for freebsd4: 61 * - FreeBSD supported $GAI. The code does not. 62 * - FreeBSD allowed classful IPv4 numeric (127.1), the code does not. 63 */ 64 65 #include <sys/cdefs.h> 66 __FBSDID("$FreeBSD$"); 67 68 #include "namespace.h" 69 #include <sys/types.h> 70 #include <sys/param.h> 71 #include <sys/socket.h> 72 #include <net/if.h> 73 #include <netinet/in.h> 74 #include <sys/queue.h> 75 #ifdef INET6 76 #include <net/if_var.h> 77 #include <sys/sysctl.h> 78 #include <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 0 116 117 static const char in_addrany[] = { 0, 0, 0, 0 }; 118 static const char in_loopback[] = { 127, 0, 0, 1 }; 119 #ifdef INET6 120 static const char in6_addrany[] = { 121 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 122 }; 123 static const char in6_loopback[] = { 124 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 125 }; 126 #endif 127 128 struct policyqueue { 129 TAILQ_ENTRY(policyqueue) pc_entry; 130 #ifdef INET6 131 struct in6_addrpolicy pc_policy; 132 #endif 133 }; 134 TAILQ_HEAD(policyhead, policyqueue); 135 136 static 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 }; 161 162 struct 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 }; 172 173 static 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 198 199 struct 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 }; 213 214 static const ns_src default_dns_files[] = { 215 { NSSRC_FILES, NS_SUCCESS }, 216 { NSSRC_DNS, NS_SUCCESS }, 217 { 0 } 218 }; 219 220 struct 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) 230 231 typedef union { 232 HEADER hdr; 233 u_char buf[MAXPACKET]; 234 } querybuf; 235 236 static int str2number(const char *); 237 static int explore_null(const struct addrinfo *, 238 const char *, struct addrinfo **); 239 static int explore_numeric(const struct addrinfo *, const char *, 240 const char *, struct addrinfo **, const char *); 241 static int explore_numeric_scope(const struct addrinfo *, const char *, 242 const char *, struct addrinfo **); 243 static int get_canonname(const struct addrinfo *, 244 struct addrinfo *, const char *); 245 static struct addrinfo *get_ai(const struct addrinfo *, 246 const struct afd *, const char *); 247 static int get_portmatch(const struct addrinfo *, const char *); 248 static int get_port(struct addrinfo *, const char *, int); 249 static const struct afd *find_afd(int); 250 static int addrconfig(struct addrinfo *); 251 static void set_source(struct ai_order *, struct policyhead *); 252 static int comp_dst(const void *, const void *); 253 #ifdef INET6 254 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); 255 #endif 256 static int gai_addr2scopetype(struct sockaddr *); 257 258 static int explore_fqdn(const struct addrinfo *, const char *, 259 const char *, struct addrinfo **); 260 261 static int reorder(struct addrinfo *); 262 static int get_addrselectpolicy(struct policyhead *); 263 static void free_addrselectpolicy(struct policyhead *); 264 static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 265 struct policyhead *); 266 static int matchlen(struct sockaddr *, struct sockaddr *); 267 268 static struct addrinfo *getanswer(const querybuf *, int, const char *, int, 269 const struct addrinfo *); 270 #if defined(RESOLVSORT) 271 static int addr4sort(struct addrinfo *); 272 #endif 273 static int _dns_getaddrinfo(void *, void *, va_list); 274 static void _sethtent(void); 275 static void _endhtent(void); 276 static struct addrinfo *_gethtent(const char *, const struct addrinfo *); 277 static int _files_getaddrinfo(void *, void *, va_list); 278 #ifdef YP 279 static struct addrinfo *_yphostent(char *, const struct addrinfo *); 280 static int _yp_getaddrinfo(void *, void *, va_list); 281 #endif 282 283 static int res_queryN(const char *, struct res_target *); 284 static int res_searchN(const char *, struct res_target *); 285 static int res_querydomainN(const char *, const char *, 286 struct res_target *); 287 288 static 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 */ 316 pthread_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) \ 325 do { \ 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) \ 335 do { \ 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) \ 343 do { \ 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) \ 351 do { \ 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))) 362 363 char * 364 gai_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 } 375 376 void 377 freeaddrinfo(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 } 391 392 static int 393 str2number(p) 394 const char *p; 395 { 396 char *ep; 397 unsigned long v; 398 399 if (*p == '\0') 400 return -1; 401 ep = NULL; 402 errno = 0; 403 v = strtoul(p, &ep, 10); 404 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) 405 return v; 406 else 407 return -1; 408 } 409 410 int 411 getaddrinfo(hostname, servname, hints, res) 412 const char *hostname, *servname; 413 const struct addrinfo *hints; 414 struct addrinfo **res; 415 { 416 struct addrinfo sentinel; 417 struct addrinfo *cur; 418 int error = 0; 419 struct addrinfo ai; 420 struct addrinfo ai0; 421 struct addrinfo *pai; 422 const struct explore *ex; 423 int numeric = 0; 424 425 memset(&sentinel, 0, sizeof(sentinel)); 426 cur = &sentinel; 427 pai = &ai; 428 pai->ai_flags = 0; 429 pai->ai_family = PF_UNSPEC; 430 pai->ai_socktype = ANY; 431 pai->ai_protocol = ANY; 432 pai->ai_addrlen = 0; 433 pai->ai_canonname = NULL; 434 pai->ai_addr = NULL; 435 pai->ai_next = NULL; 436 437 if (hostname == NULL && servname == NULL) 438 return EAI_NONAME; 439 if (hints) { 440 /* error check for hints */ 441 if (hints->ai_addrlen || hints->ai_canonname || 442 hints->ai_addr || hints->ai_next) 443 ERR(EAI_BADHINTS); /* xxx */ 444 if (hints->ai_flags & ~AI_MASK) 445 ERR(EAI_BADFLAGS); 446 switch (hints->ai_family) { 447 case PF_UNSPEC: 448 case PF_INET: 449 #ifdef INET6 450 case PF_INET6: 451 #endif 452 break; 453 default: 454 ERR(EAI_FAMILY); 455 } 456 memcpy(pai, hints, sizeof(*pai)); 457 458 /* 459 * if both socktype/protocol are specified, check if they 460 * are meaningful combination. 461 */ 462 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 463 for (ex = explore; ex->e_af >= 0; ex++) { 464 if (pai->ai_family != ex->e_af) 465 continue; 466 if (ex->e_socktype == ANY) 467 continue; 468 if (ex->e_protocol == ANY) 469 continue; 470 if (pai->ai_socktype == ex->e_socktype && 471 pai->ai_protocol != ex->e_protocol) { 472 ERR(EAI_BADHINTS); 473 } 474 } 475 } 476 } 477 478 /* 479 * post-2553: AI_ALL and AI_V4MAPPED are effective only against 480 * AF_INET6 query. They need to be ignored if specified in other 481 * occassions. 482 */ 483 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { 484 case AI_V4MAPPED: 485 case AI_ALL | AI_V4MAPPED: 486 if (pai->ai_family != AF_INET6) 487 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 488 break; 489 case AI_ALL: 490 #if 1 491 /* illegal */ 492 ERR(EAI_BADFLAGS); 493 #else 494 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); 495 #endif 496 break; 497 } 498 499 /* 500 * check for special cases. (1) numeric servname is disallowed if 501 * socktype/protocol are left unspecified. (2) servname is disallowed 502 * for raw and other inet{,6} sockets. 503 */ 504 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 505 #ifdef PF_INET6 506 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 507 #endif 508 ) { 509 ai0 = *pai; /* backup *pai */ 510 511 if (pai->ai_family == PF_UNSPEC) { 512 #ifdef PF_INET6 513 pai->ai_family = PF_INET6; 514 #else 515 pai->ai_family = PF_INET; 516 #endif 517 } 518 error = get_portmatch(pai, servname); 519 if (error) 520 ERR(error); 521 522 *pai = ai0; 523 } 524 525 ai0 = *pai; 526 527 /* NULL hostname, or numeric hostname */ 528 for (ex = explore; ex->e_af >= 0; ex++) { 529 *pai = ai0; 530 531 /* PF_UNSPEC entries are prepared for DNS queries only */ 532 if (ex->e_af == PF_UNSPEC) 533 continue; 534 535 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 536 continue; 537 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 538 continue; 539 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 540 continue; 541 542 if (pai->ai_family == PF_UNSPEC) 543 pai->ai_family = ex->e_af; 544 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 545 pai->ai_socktype = ex->e_socktype; 546 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 547 pai->ai_protocol = ex->e_protocol; 548 549 if (hostname == NULL) 550 error = explore_null(pai, servname, &cur->ai_next); 551 else 552 error = explore_numeric_scope(pai, hostname, servname, 553 &cur->ai_next); 554 555 if (error) 556 goto free; 557 558 while (cur && cur->ai_next) 559 cur = cur->ai_next; 560 } 561 562 /* 563 * XXX 564 * If numreic representation of AF1 can be interpreted as FQDN 565 * representation of AF2, we need to think again about the code below. 566 */ 567 if (sentinel.ai_next) { 568 numeric = 1; 569 goto good; 570 } 571 572 if (hostname == NULL) 573 ERR(EAI_NONAME); /* used to be EAI_NODATA */ 574 if (pai->ai_flags & AI_NUMERICHOST) 575 ERR(EAI_NONAME); 576 577 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) 578 ERR(EAI_FAIL); 579 580 /* 581 * hostname as alphabetical name. 582 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 583 * outer loop by AFs. 584 */ 585 for (ex = explore; ex->e_af >= 0; ex++) { 586 *pai = ai0; 587 588 /* require exact match for family field */ 589 if (pai->ai_family != ex->e_af) 590 continue; 591 592 if (!MATCH(pai->ai_socktype, ex->e_socktype, 593 WILD_SOCKTYPE(ex))) { 594 continue; 595 } 596 if (!MATCH(pai->ai_protocol, ex->e_protocol, 597 WILD_PROTOCOL(ex))) { 598 continue; 599 } 600 601 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 602 pai->ai_socktype = ex->e_socktype; 603 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 604 pai->ai_protocol = ex->e_protocol; 605 606 error = explore_fqdn(pai, hostname, servname, 607 &cur->ai_next); 608 609 while (cur && cur->ai_next) 610 cur = cur->ai_next; 611 } 612 613 /* XXX inhibit errors if we have the result */ 614 if (sentinel.ai_next) 615 error = 0; 616 617 good: 618 /* 619 * ensure we return either: 620 * - error == 0, non-NULL *res 621 * - error != 0, NULL *res 622 */ 623 if (error == 0) { 624 if (sentinel.ai_next) { 625 /* 626 * If the returned entry is for an active connection, 627 * and the given name is not numeric, reorder the 628 * list, so that the application would try the list 629 * in the most efficient order. 630 */ 631 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { 632 if (!numeric) 633 (void)reorder(&sentinel); 634 } 635 *res = sentinel.ai_next; 636 return SUCCESS; 637 } else 638 error = EAI_FAIL; 639 } 640 free: 641 bad: 642 if (sentinel.ai_next) 643 freeaddrinfo(sentinel.ai_next); 644 *res = NULL; 645 return error; 646 } 647 648 static int 649 reorder(sentinel) 650 struct addrinfo *sentinel; 651 { 652 struct addrinfo *ai, **aip; 653 struct ai_order *aio; 654 int i, n; 655 struct policyhead policyhead; 656 657 /* count the number of addrinfo elements for sorting. */ 658 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) 659 ; 660 661 /* 662 * If the number is small enough, we can skip the reordering process. 663 */ 664 if (n <= 1) 665 return(n); 666 667 /* allocate a temporary array for sort and initialization of it. */ 668 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 669 return(n); /* give up reordering */ 670 memset(aio, 0, sizeof(*aio) * n); 671 672 /* retrieve address selection policy from the kernel */ 673 TAILQ_INIT(&policyhead); 674 if (!get_addrselectpolicy(&policyhead)) { 675 /* no policy is installed into kernel, we don't sort. */ 676 free(aio); 677 return (n); 678 } 679 680 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { 681 aio[i].aio_ai = ai; 682 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); 683 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, 684 &policyhead); 685 set_source(&aio[i], &policyhead); 686 } 687 688 /* perform sorting. */ 689 qsort(aio, n, sizeof(*aio), comp_dst); 690 691 /* reorder the addrinfo chain. */ 692 for (i = 0, aip = &sentinel->ai_next; i < n; i++) { 693 *aip = aio[i].aio_ai; 694 aip = &aio[i].aio_ai->ai_next; 695 } 696 *aip = NULL; 697 698 /* cleanup and return */ 699 free(aio); 700 free_addrselectpolicy(&policyhead); 701 return(n); 702 } 703 704 static int 705 get_addrselectpolicy(head) 706 struct policyhead *head; 707 { 708 #ifdef INET6 709 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 710 size_t l; 711 char *buf; 712 struct in6_addrpolicy *pol, *ep; 713 714 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 715 return (0); 716 if ((buf = malloc(l)) == NULL) 717 return (0); 718 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 719 free(buf); 720 return (0); 721 } 722 723 ep = (struct in6_addrpolicy *)(buf + l); 724 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 725 struct policyqueue *new; 726 727 if ((new = malloc(sizeof(*new))) == NULL) { 728 free_addrselectpolicy(head); /* make the list empty */ 729 break; 730 } 731 new->pc_policy = *pol; 732 TAILQ_INSERT_TAIL(head, new, pc_entry); 733 } 734 735 free(buf); 736 return (1); 737 #else 738 return (0); 739 #endif 740 } 741 742 static void 743 free_addrselectpolicy(head) 744 struct policyhead *head; 745 { 746 struct policyqueue *ent, *nent; 747 748 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 749 nent = TAILQ_NEXT(ent, pc_entry); 750 TAILQ_REMOVE(head, ent, pc_entry); 751 free(ent); 752 } 753 } 754 755 static struct policyqueue * 756 match_addrselectpolicy(addr, head) 757 struct sockaddr *addr; 758 struct policyhead *head; 759 { 760 #ifdef INET6 761 struct policyqueue *ent, *bestent = NULL; 762 struct in6_addrpolicy *pol; 763 int matchlen, bestmatchlen = -1; 764 u_char *mp, *ep, *k, *p, m; 765 struct sockaddr_in6 key; 766 767 switch(addr->sa_family) { 768 case AF_INET6: 769 key = *(struct sockaddr_in6 *)addr; 770 break; 771 case AF_INET: 772 /* convert the address into IPv4-mapped IPv6 address. */ 773 memset(&key, 0, sizeof(key)); 774 key.sin6_family = AF_INET6; 775 key.sin6_len = sizeof(key); 776 key.sin6_addr.s6_addr[10] = 0xff; 777 key.sin6_addr.s6_addr[11] = 0xff; 778 memcpy(&key.sin6_addr.s6_addr[12], 779 &((struct sockaddr_in *)addr)->sin_addr, 4); 780 break; 781 default: 782 return(NULL); 783 } 784 785 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 786 pol = &ent->pc_policy; 787 matchlen = 0; 788 789 mp = (u_char *)&pol->addrmask.sin6_addr; 790 ep = mp + 16; /* XXX: scope field? */ 791 k = (u_char *)&key.sin6_addr; 792 p = (u_char *)&pol->addr.sin6_addr; 793 for (; mp < ep && *mp; mp++, k++, p++) { 794 m = *mp; 795 if ((*k & m) != *p) 796 goto next; /* not match */ 797 if (m == 0xff) /* short cut for a typical case */ 798 matchlen += 8; 799 else { 800 while (m >= 0x80) { 801 matchlen++; 802 m <<= 1; 803 } 804 } 805 } 806 807 /* matched. check if this is better than the current best. */ 808 if (matchlen > bestmatchlen) { 809 bestent = ent; 810 bestmatchlen = matchlen; 811 } 812 813 next: 814 continue; 815 } 816 817 return(bestent); 818 #else 819 return(NULL); 820 #endif 821 822 } 823 824 static void 825 set_source(aio, ph) 826 struct ai_order *aio; 827 struct policyhead *ph; 828 { 829 struct addrinfo ai = *aio->aio_ai; 830 struct sockaddr_storage ss; 831 int s, srclen; 832 833 /* set unspec ("no source is available"), just in case */ 834 aio->aio_srcsa.sa_family = AF_UNSPEC; 835 aio->aio_srcscope = -1; 836 837 switch(ai.ai_family) { 838 case AF_INET: 839 #ifdef INET6 840 case AF_INET6: 841 #endif 842 break; 843 default: /* ignore unsupported AFs explicitly */ 844 return; 845 } 846 847 /* XXX: make a dummy addrinfo to call connect() */ 848 ai.ai_socktype = SOCK_DGRAM; 849 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ 850 ai.ai_next = NULL; 851 memset(&ss, 0, sizeof(ss)); 852 memcpy(&ss, ai.ai_addr, ai.ai_addrlen); 853 ai.ai_addr = (struct sockaddr *)&ss; 854 get_port(&ai, "1", 0); 855 856 /* open a socket to get the source address for the given dst */ 857 if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0) 858 return; /* give up */ 859 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) 860 goto cleanup; 861 srclen = ai.ai_addrlen; 862 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 863 aio->aio_srcsa.sa_family = AF_UNSPEC; 864 goto cleanup; 865 } 866 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 867 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 868 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); 869 #ifdef INET6 870 if (ai.ai_family == AF_INET6) { 871 struct in6_ifreq ifr6; 872 u_int32_t flags6; 873 874 /* XXX: interface name should not be hardcoded */ 875 strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name)); 876 memset(&ifr6, 0, sizeof(ifr6)); 877 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); 878 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 879 flags6 = ifr6.ifr_ifru.ifru_flags6; 880 if ((flags6 & IN6_IFF_DEPRECATED)) 881 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 882 } 883 } 884 #endif 885 886 cleanup: 887 _close(s); 888 return; 889 } 890 891 static int 892 matchlen(src, dst) 893 struct sockaddr *src, *dst; 894 { 895 int match = 0; 896 u_char *s, *d; 897 u_char *lim, r; 898 int addrlen; 899 900 switch (src->sa_family) { 901 #ifdef INET6 902 case AF_INET6: 903 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 904 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 905 addrlen = sizeof(struct in6_addr); 906 lim = s + addrlen; 907 break; 908 #endif 909 case AF_INET: 910 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 911 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 912 addrlen = sizeof(struct in_addr); 913 lim = s + addrlen; 914 break; 915 default: 916 return(0); 917 } 918 919 while (s < lim) 920 if ((r = (*d++ ^ *s++)) != 0) { 921 while (r < addrlen * 8) { 922 match++; 923 r <<= 1; 924 } 925 break; 926 } else 927 match += 8; 928 return(match); 929 } 930 931 static int 932 comp_dst(arg1, arg2) 933 const void *arg1, *arg2; 934 { 935 const struct ai_order *dst1 = arg1, *dst2 = arg2; 936 937 /* 938 * Rule 1: Avoid unusable destinations. 939 * XXX: we currently do not consider if an appropriate route exists. 940 */ 941 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 942 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 943 return(-1); 944 } 945 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 946 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 947 return(1); 948 } 949 950 /* Rule 2: Prefer matching scope. */ 951 if (dst1->aio_dstscope == dst1->aio_srcscope && 952 dst2->aio_dstscope != dst2->aio_srcscope) { 953 return(-1); 954 } 955 if (dst1->aio_dstscope != dst1->aio_srcscope && 956 dst2->aio_dstscope == dst2->aio_srcscope) { 957 return(1); 958 } 959 960 /* Rule 3: Avoid deprecated addresses. */ 961 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 962 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 963 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 964 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 965 return(-1); 966 } 967 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 968 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 969 return(1); 970 } 971 } 972 973 /* Rule 4: Prefer home addresses. */ 974 /* XXX: not implemented yet */ 975 976 /* Rule 5: Prefer matching label. */ 977 #ifdef INET6 978 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 979 dst1->aio_srcpolicy->pc_policy.label == 980 dst1->aio_dstpolicy->pc_policy.label && 981 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 982 dst2->aio_srcpolicy->pc_policy.label != 983 dst2->aio_dstpolicy->pc_policy.label)) { 984 return(-1); 985 } 986 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 987 dst2->aio_srcpolicy->pc_policy.label == 988 dst2->aio_dstpolicy->pc_policy.label && 989 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 990 dst1->aio_srcpolicy->pc_policy.label != 991 dst1->aio_dstpolicy->pc_policy.label)) { 992 return(1); 993 } 994 #endif 995 996 /* Rule 6: Prefer higher precedence. */ 997 #ifdef INET6 998 if (dst1->aio_dstpolicy && 999 (dst2->aio_dstpolicy == NULL || 1000 dst1->aio_dstpolicy->pc_policy.preced > 1001 dst2->aio_dstpolicy->pc_policy.preced)) { 1002 return(-1); 1003 } 1004 if (dst2->aio_dstpolicy && 1005 (dst1->aio_dstpolicy == NULL || 1006 dst2->aio_dstpolicy->pc_policy.preced > 1007 dst1->aio_dstpolicy->pc_policy.preced)) { 1008 return(1); 1009 } 1010 #endif 1011 1012 /* Rule 7: Prefer native transport. */ 1013 /* XXX: not implemented yet */ 1014 1015 /* Rule 8: Prefer smaller scope. */ 1016 if (dst1->aio_dstscope >= 0 && 1017 dst1->aio_dstscope < dst2->aio_dstscope) { 1018 return(-1); 1019 } 1020 if (dst2->aio_dstscope >= 0 && 1021 dst2->aio_dstscope < dst1->aio_dstscope) { 1022 return(1); 1023 } 1024 1025 /* 1026 * Rule 9: Use longest matching prefix. 1027 * We compare the match length in a same AF only. 1028 */ 1029 if (dst1->aio_ai->ai_addr->sa_family == 1030 dst2->aio_ai->ai_addr->sa_family) { 1031 if (dst1->aio_matchlen > dst2->aio_matchlen) { 1032 return(-1); 1033 } 1034 if (dst1->aio_matchlen < dst2->aio_matchlen) { 1035 return(1); 1036 } 1037 } 1038 1039 /* Rule 10: Otherwise, leave the order unchanged. */ 1040 return(-1); 1041 } 1042 1043 /* 1044 * Copy from scope.c. 1045 * XXX: we should standardize the functions and link them as standard 1046 * library. 1047 */ 1048 static int 1049 gai_addr2scopetype(sa) 1050 struct sockaddr *sa; 1051 { 1052 #ifdef INET6 1053 struct sockaddr_in6 *sa6; 1054 #endif 1055 struct sockaddr_in *sa4; 1056 1057 switch(sa->sa_family) { 1058 #ifdef INET6 1059 case AF_INET6: 1060 sa6 = (struct sockaddr_in6 *)sa; 1061 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1062 /* just use the scope field of the multicast address */ 1063 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1064 } 1065 /* 1066 * Unicast addresses: map scope type to corresponding scope 1067 * value defined for multcast addresses. 1068 * XXX: hardcoded scope type values are bad... 1069 */ 1070 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1071 return(1); /* node local scope */ 1072 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1073 return(2); /* link-local scope */ 1074 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1075 return(5); /* site-local scope */ 1076 return(14); /* global scope */ 1077 break; 1078 #endif 1079 case AF_INET: 1080 /* 1081 * IPv4 pseudo scoping according to RFC 3484. 1082 */ 1083 sa4 = (struct sockaddr_in *)sa; 1084 /* IPv4 autoconfiguration addresses have link-local scope. */ 1085 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1086 ((u_char *)&sa4->sin_addr)[1] == 254) 1087 return(2); 1088 /* Private addresses have site-local scope. */ 1089 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1090 (((u_char *)&sa4->sin_addr)[0] == 172 && 1091 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1092 (((u_char *)&sa4->sin_addr)[0] == 192 && 1093 ((u_char *)&sa4->sin_addr)[1] == 168)) 1094 return(14); /* XXX: It should be 5 unless NAT */ 1095 /* Loopback addresses have link-local scope. */ 1096 if (((u_char *)&sa4->sin_addr)[0] == 127) 1097 return(2); 1098 return(14); 1099 break; 1100 default: 1101 errno = EAFNOSUPPORT; /* is this a good error? */ 1102 return(-1); 1103 } 1104 } 1105 1106 /* 1107 * hostname == NULL. 1108 * passive socket -> anyaddr (0.0.0.0 or ::) 1109 * non-passive socket -> localhost (127.0.0.1 or ::1) 1110 */ 1111 static int 1112 explore_null(pai, servname, res) 1113 const struct addrinfo *pai; 1114 const char *servname; 1115 struct addrinfo **res; 1116 { 1117 int s; 1118 const struct afd *afd; 1119 struct addrinfo *cur; 1120 struct addrinfo sentinel; 1121 int error; 1122 1123 *res = NULL; 1124 sentinel.ai_next = NULL; 1125 cur = &sentinel; 1126 1127 /* 1128 * filter out AFs that are not supported by the kernel 1129 * XXX errno? 1130 */ 1131 s = _socket(pai->ai_family, SOCK_DGRAM, 0); 1132 if (s < 0) { 1133 if (errno != EMFILE) 1134 return 0; 1135 } else 1136 _close(s); 1137 1138 /* 1139 * if the servname does not match socktype/protocol, ignore it. 1140 */ 1141 if (get_portmatch(pai, servname) != 0) 1142 return 0; 1143 1144 afd = find_afd(pai->ai_family); 1145 if (afd == NULL) 1146 return 0; 1147 1148 if (pai->ai_flags & AI_PASSIVE) { 1149 GET_AI(cur->ai_next, afd, afd->a_addrany); 1150 /* xxx meaningless? 1151 * GET_CANONNAME(cur->ai_next, "anyaddr"); 1152 */ 1153 GET_PORT(cur->ai_next, servname); 1154 } else { 1155 GET_AI(cur->ai_next, afd, afd->a_loopback); 1156 /* xxx meaningless? 1157 * GET_CANONNAME(cur->ai_next, "localhost"); 1158 */ 1159 GET_PORT(cur->ai_next, servname); 1160 } 1161 cur = cur->ai_next; 1162 1163 *res = sentinel.ai_next; 1164 return 0; 1165 1166 free: 1167 if (sentinel.ai_next) 1168 freeaddrinfo(sentinel.ai_next); 1169 return error; 1170 } 1171 1172 /* 1173 * numeric hostname 1174 */ 1175 static int 1176 explore_numeric(pai, hostname, servname, res, canonname) 1177 const struct addrinfo *pai; 1178 const char *hostname; 1179 const char *servname; 1180 struct addrinfo **res; 1181 const char *canonname; 1182 { 1183 const struct afd *afd; 1184 struct addrinfo *cur; 1185 struct addrinfo sentinel; 1186 int error; 1187 char pton[PTON_MAX]; 1188 1189 *res = NULL; 1190 sentinel.ai_next = NULL; 1191 cur = &sentinel; 1192 1193 /* 1194 * if the servname does not match socktype/protocol, ignore it. 1195 */ 1196 if (get_portmatch(pai, servname) != 0) 1197 return 0; 1198 1199 afd = find_afd(pai->ai_family); 1200 if (afd == NULL) 1201 return 0; 1202 1203 switch (afd->a_af) { 1204 #if 1 /*X/Open spec*/ 1205 case AF_INET: 1206 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 1207 if (pai->ai_family == afd->a_af || 1208 pai->ai_family == PF_UNSPEC /*?*/) { 1209 GET_AI(cur->ai_next, afd, pton); 1210 GET_PORT(cur->ai_next, servname); 1211 if ((pai->ai_flags & AI_CANONNAME)) { 1212 /* 1213 * Set the numeric address itself as 1214 * the canonical name, based on a 1215 * clarification in rfc3493. 1216 */ 1217 GET_CANONNAME(cur->ai_next, canonname); 1218 } 1219 while (cur && cur->ai_next) 1220 cur = cur->ai_next; 1221 } else 1222 ERR(EAI_FAMILY); /*xxx*/ 1223 } 1224 break; 1225 #endif 1226 default: 1227 if (inet_pton(afd->a_af, hostname, pton) == 1) { 1228 if (pai->ai_family == afd->a_af || 1229 pai->ai_family == PF_UNSPEC /*?*/) { 1230 GET_AI(cur->ai_next, afd, pton); 1231 GET_PORT(cur->ai_next, servname); 1232 if ((pai->ai_flags & AI_CANONNAME)) { 1233 /* 1234 * Set the numeric address itself as 1235 * the canonical name, based on a 1236 * clarification in rfc3493. 1237 */ 1238 GET_CANONNAME(cur->ai_next, canonname); 1239 } 1240 while (cur && cur->ai_next) 1241 cur = cur->ai_next; 1242 } else 1243 ERR(EAI_FAMILY); /* XXX */ 1244 } 1245 break; 1246 } 1247 1248 *res = sentinel.ai_next; 1249 return 0; 1250 1251 free: 1252 bad: 1253 if (sentinel.ai_next) 1254 freeaddrinfo(sentinel.ai_next); 1255 return error; 1256 } 1257 1258 /* 1259 * numeric hostname with scope 1260 */ 1261 static int 1262 explore_numeric_scope(pai, hostname, servname, res) 1263 const struct addrinfo *pai; 1264 const char *hostname; 1265 const char *servname; 1266 struct addrinfo **res; 1267 { 1268 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 1269 return explore_numeric(pai, hostname, servname, res, hostname); 1270 #else 1271 const struct afd *afd; 1272 struct addrinfo *cur; 1273 int error; 1274 char *cp, *hostname2 = NULL, *scope, *addr; 1275 struct sockaddr_in6 *sin6; 1276 1277 /* 1278 * if the servname does not match socktype/protocol, ignore it. 1279 */ 1280 if (get_portmatch(pai, servname) != 0) 1281 return 0; 1282 1283 afd = find_afd(pai->ai_family); 1284 if (afd == NULL) 1285 return 0; 1286 1287 if (!afd->a_scoped) 1288 return explore_numeric(pai, hostname, servname, res, hostname); 1289 1290 cp = strchr(hostname, SCOPE_DELIMITER); 1291 if (cp == NULL) 1292 return explore_numeric(pai, hostname, servname, res, hostname); 1293 1294 /* 1295 * Handle special case of <scoped_address><delimiter><scope id> 1296 */ 1297 hostname2 = strdup(hostname); 1298 if (hostname2 == NULL) 1299 return EAI_MEMORY; 1300 /* terminate at the delimiter */ 1301 hostname2[cp - hostname] = '\0'; 1302 addr = hostname2; 1303 scope = cp + 1; 1304 1305 error = explore_numeric(pai, addr, servname, res, hostname); 1306 if (error == 0) { 1307 u_int32_t scopeid; 1308 1309 for (cur = *res; cur; cur = cur->ai_next) { 1310 if (cur->ai_family != AF_INET6) 1311 continue; 1312 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; 1313 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { 1314 free(hostname2); 1315 return(EAI_NONAME); /* XXX: is return OK? */ 1316 } 1317 sin6->sin6_scope_id = scopeid; 1318 } 1319 } 1320 1321 free(hostname2); 1322 1323 return error; 1324 #endif 1325 } 1326 1327 static int 1328 get_canonname(pai, ai, str) 1329 const struct addrinfo *pai; 1330 struct addrinfo *ai; 1331 const char *str; 1332 { 1333 if ((pai->ai_flags & AI_CANONNAME) != 0) { 1334 ai->ai_canonname = strdup(str); 1335 if (ai->ai_canonname == NULL) 1336 return EAI_MEMORY; 1337 } 1338 return 0; 1339 } 1340 1341 static struct addrinfo * 1342 get_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 1412 static int 1413 get_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 1423 static int 1424 get_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 port = str2number(servname); 1461 if (port >= 0) { 1462 if (!allownumeric) 1463 return EAI_SERVICE; 1464 if (port < 0 || port > 65535) 1465 return EAI_SERVICE; 1466 port = htons(port); 1467 } else { 1468 if (ai->ai_flags & AI_NUMERICSERV) 1469 return EAI_NONAME; 1470 switch (ai->ai_socktype) { 1471 case SOCK_DGRAM: 1472 proto = "udp"; 1473 break; 1474 case SOCK_STREAM: 1475 proto = "tcp"; 1476 break; 1477 default: 1478 proto = NULL; 1479 break; 1480 } 1481 1482 THREAD_LOCK(); 1483 if ((sp = getservbyname(servname, proto)) == NULL) { 1484 THREAD_UNLOCK(); 1485 return EAI_SERVICE; 1486 } 1487 port = sp->s_port; 1488 THREAD_UNLOCK(); 1489 } 1490 1491 if (!matchonly) { 1492 switch (ai->ai_family) { 1493 case AF_INET: 1494 ((struct sockaddr_in *)(void *) 1495 ai->ai_addr)->sin_port = port; 1496 break; 1497 #ifdef INET6 1498 case AF_INET6: 1499 ((struct sockaddr_in6 *)(void *) 1500 ai->ai_addr)->sin6_port = port; 1501 break; 1502 #endif 1503 } 1504 } 1505 1506 return 0; 1507 } 1508 1509 static const struct afd * 1510 find_afd(af) 1511 int af; 1512 { 1513 const struct afd *afd; 1514 1515 if (af == PF_UNSPEC) 1516 return NULL; 1517 for (afd = afdl; afd->a_af; afd++) { 1518 if (afd->a_af == af) 1519 return afd; 1520 } 1521 return NULL; 1522 } 1523 1524 /* 1525 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 1526 * will take care of it. 1527 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 1528 * if the code is right or not. 1529 * 1530 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with 1531 * _dns_getaddrinfo. 1532 */ 1533 static int 1534 addrconfig(pai) 1535 struct addrinfo *pai; 1536 { 1537 int s, af; 1538 1539 /* 1540 * TODO: 1541 * Note that implementation dependent test for address 1542 * configuration should be done everytime called 1543 * (or apropriate interval), 1544 * because addresses will be dynamically assigned or deleted. 1545 */ 1546 af = pai->ai_family; 1547 if (af == AF_UNSPEC) { 1548 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 1549 af = AF_INET; 1550 else { 1551 _close(s); 1552 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) 1553 af = AF_INET6; 1554 else 1555 _close(s); 1556 } 1557 } 1558 if (af != AF_UNSPEC) { 1559 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 1560 return 0; 1561 _close(s); 1562 } 1563 pai->ai_family = af; 1564 return 1; 1565 } 1566 1567 #ifdef INET6 1568 /* convert a string to a scope identifier. XXX: IPv6 specific */ 1569 static int 1570 ip6_str2scopeid(scope, sin6, scopeid) 1571 char *scope; 1572 struct sockaddr_in6 *sin6; 1573 u_int32_t *scopeid; 1574 { 1575 u_long lscopeid; 1576 struct in6_addr *a6; 1577 char *ep; 1578 1579 a6 = &sin6->sin6_addr; 1580 1581 /* empty scopeid portion is invalid */ 1582 if (*scope == '\0') 1583 return -1; 1584 1585 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1586 /* 1587 * We currently assume a one-to-one mapping between links 1588 * and interfaces, so we simply use interface indices for 1589 * like-local scopes. 1590 */ 1591 *scopeid = if_nametoindex(scope); 1592 if (*scopeid == 0) 1593 goto trynumeric; 1594 return 0; 1595 } 1596 1597 /* still unclear about literal, allow numeric only - placeholder */ 1598 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1599 goto trynumeric; 1600 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1601 goto trynumeric; 1602 else 1603 goto trynumeric; /* global */ 1604 1605 /* try to convert to a numeric id as a last resort */ 1606 trynumeric: 1607 errno = 0; 1608 lscopeid = strtoul(scope, &ep, 10); 1609 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); 1610 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) 1611 return 0; 1612 else 1613 return -1; 1614 } 1615 #endif 1616 1617 /* 1618 * FQDN hostname, DNS lookup 1619 */ 1620 static int 1621 explore_fqdn(pai, hostname, servname, res) 1622 const struct addrinfo *pai; 1623 const char *hostname; 1624 const char *servname; 1625 struct addrinfo **res; 1626 { 1627 struct addrinfo *result; 1628 struct addrinfo *cur; 1629 int error = 0; 1630 static const ns_dtab dtab[] = { 1631 NS_FILES_CB(_files_getaddrinfo, NULL) 1632 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ 1633 NS_NIS_CB(_yp_getaddrinfo, NULL) 1634 { 0 } 1635 }; 1636 1637 result = NULL; 1638 1639 /* 1640 * if the servname does not match socktype/protocol, ignore it. 1641 */ 1642 if (get_portmatch(pai, servname) != 0) 1643 return 0; 1644 1645 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", 1646 default_dns_files, hostname, pai)) { 1647 case NS_TRYAGAIN: 1648 error = EAI_AGAIN; 1649 goto free; 1650 case NS_UNAVAIL: 1651 error = EAI_FAIL; 1652 goto free; 1653 case NS_NOTFOUND: 1654 error = EAI_NONAME; 1655 goto free; 1656 case NS_SUCCESS: 1657 error = 0; 1658 for (cur = result; cur; cur = cur->ai_next) { 1659 GET_PORT(cur, servname); 1660 /* canonname should be filled already */ 1661 } 1662 break; 1663 } 1664 1665 *res = result; 1666 1667 return 0; 1668 1669 free: 1670 if (result) 1671 freeaddrinfo(result); 1672 return error; 1673 } 1674 1675 #ifdef DEBUG 1676 static const char AskedForGot[] = 1677 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 1678 #endif 1679 static FILE *hostf = NULL; 1680 1681 static struct addrinfo * 1682 getanswer(answer, anslen, qname, qtype, pai) 1683 const querybuf *answer; 1684 int anslen; 1685 const char *qname; 1686 int qtype; 1687 const struct addrinfo *pai; 1688 { 1689 struct addrinfo sentinel, *cur; 1690 struct addrinfo ai; 1691 const struct afd *afd; 1692 char *canonname; 1693 const HEADER *hp; 1694 const u_char *cp; 1695 int n; 1696 const u_char *eom; 1697 char *bp, *ep; 1698 int type, class, ancount, qdcount; 1699 int haveanswer, had_error; 1700 char tbuf[MAXDNAME]; 1701 int (*name_ok)(const char *); 1702 char hostbuf[8*1024]; 1703 1704 memset(&sentinel, 0, sizeof(sentinel)); 1705 cur = &sentinel; 1706 1707 canonname = NULL; 1708 eom = answer->buf + anslen; 1709 switch (qtype) { 1710 case T_A: 1711 case T_AAAA: 1712 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ 1713 name_ok = res_hnok; 1714 break; 1715 default: 1716 return (NULL); /* XXX should be abort(); */ 1717 } 1718 /* 1719 * find first satisfactory answer 1720 */ 1721 hp = &answer->hdr; 1722 ancount = ntohs(hp->ancount); 1723 qdcount = ntohs(hp->qdcount); 1724 bp = hostbuf; 1725 ep = hostbuf + sizeof hostbuf; 1726 cp = answer->buf + HFIXEDSZ; 1727 if (qdcount != 1) { 1728 h_errno = NO_RECOVERY; 1729 return (NULL); 1730 } 1731 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1732 if ((n < 0) || !(*name_ok)(bp)) { 1733 h_errno = NO_RECOVERY; 1734 return (NULL); 1735 } 1736 cp += n + QFIXEDSZ; 1737 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { 1738 /* res_send() has already verified that the query name is the 1739 * same as the one we sent; this just gets the expanded name 1740 * (i.e., with the succeeding search-domain tacked on). 1741 */ 1742 n = strlen(bp) + 1; /* for the \0 */ 1743 if (n >= MAXHOSTNAMELEN) { 1744 h_errno = NO_RECOVERY; 1745 return (NULL); 1746 } 1747 canonname = bp; 1748 bp += n; 1749 /* The qname can be abbreviated, but h_name is now absolute. */ 1750 qname = canonname; 1751 } 1752 haveanswer = 0; 1753 had_error = 0; 1754 while (ancount-- > 0 && cp < eom && !had_error) { 1755 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 1756 if ((n < 0) || !(*name_ok)(bp)) { 1757 had_error++; 1758 continue; 1759 } 1760 cp += n; /* name */ 1761 type = _getshort(cp); 1762 cp += INT16SZ; /* type */ 1763 class = _getshort(cp); 1764 cp += INT16SZ + INT32SZ; /* class, TTL */ 1765 n = _getshort(cp); 1766 cp += INT16SZ; /* len */ 1767 if (class != C_IN) { 1768 /* XXX - debug? syslog? */ 1769 cp += n; 1770 continue; /* XXX - had_error++ ? */ 1771 } 1772 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && 1773 type == T_CNAME) { 1774 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 1775 if ((n < 0) || !(*name_ok)(tbuf)) { 1776 had_error++; 1777 continue; 1778 } 1779 cp += n; 1780 /* Get canonical name. */ 1781 n = strlen(tbuf) + 1; /* for the \0 */ 1782 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 1783 had_error++; 1784 continue; 1785 } 1786 strlcpy(bp, tbuf, ep - bp); 1787 canonname = bp; 1788 bp += n; 1789 continue; 1790 } 1791 if (qtype == T_ANY) { 1792 if (!(type == T_A || type == T_AAAA)) { 1793 cp += n; 1794 continue; 1795 } 1796 } else if (type != qtype) { 1797 #ifdef DEBUG 1798 if (type != T_KEY && type != T_SIG) 1799 syslog(LOG_NOTICE|LOG_AUTH, 1800 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 1801 qname, p_class(C_IN), p_type(qtype), 1802 p_type(type)); 1803 #endif 1804 cp += n; 1805 continue; /* XXX - had_error++ ? */ 1806 } 1807 switch (type) { 1808 case T_A: 1809 case T_AAAA: 1810 if (strcasecmp(canonname, bp) != 0) { 1811 #ifdef DEBUG 1812 syslog(LOG_NOTICE|LOG_AUTH, 1813 AskedForGot, canonname, bp); 1814 #endif 1815 cp += n; 1816 continue; /* XXX - had_error++ ? */ 1817 } 1818 if (type == T_A && n != INADDRSZ) { 1819 cp += n; 1820 continue; 1821 } 1822 if (type == T_AAAA && n != IN6ADDRSZ) { 1823 cp += n; 1824 continue; 1825 } 1826 #ifdef FILTER_V4MAPPED 1827 if (type == T_AAAA) { 1828 struct in6_addr in6; 1829 memcpy(&in6, cp, sizeof(in6)); 1830 if (IN6_IS_ADDR_V4MAPPED(&in6)) { 1831 cp += n; 1832 continue; 1833 } 1834 } 1835 #endif 1836 if (!haveanswer) { 1837 int nn; 1838 1839 canonname = bp; 1840 nn = strlen(bp) + 1; /* for the \0 */ 1841 bp += nn; 1842 } 1843 1844 /* don't overwrite pai */ 1845 ai = *pai; 1846 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; 1847 afd = find_afd(ai.ai_family); 1848 if (afd == NULL) { 1849 cp += n; 1850 continue; 1851 } 1852 cur->ai_next = get_ai(&ai, afd, (const char *)cp); 1853 if (cur->ai_next == NULL) 1854 had_error++; 1855 while (cur && cur->ai_next) 1856 cur = cur->ai_next; 1857 cp += n; 1858 break; 1859 default: 1860 abort(); 1861 } 1862 if (!had_error) 1863 haveanswer++; 1864 } 1865 if (haveanswer) { 1866 #if defined(RESOLVSORT) 1867 /* 1868 * We support only IPv4 address for backward 1869 * compatibility against gethostbyname(3). 1870 */ 1871 if (_res.nsort && qtype == T_A) { 1872 if (addr4sort(&sentinel) < 0) { 1873 freeaddrinfo(sentinel.ai_next); 1874 h_errno = NO_RECOVERY; 1875 return NULL; 1876 } 1877 } 1878 #endif /*RESOLVSORT*/ 1879 if (!canonname) 1880 (void)get_canonname(pai, sentinel.ai_next, qname); 1881 else 1882 (void)get_canonname(pai, sentinel.ai_next, canonname); 1883 h_errno = NETDB_SUCCESS; 1884 return sentinel.ai_next; 1885 } 1886 1887 h_errno = NO_RECOVERY; 1888 return NULL; 1889 } 1890 1891 #ifdef RESOLVSORT 1892 struct addr_ptr { 1893 struct addrinfo *ai; 1894 int aval; 1895 }; 1896 1897 static int 1898 addr4sort(struct addrinfo *sentinel) 1899 { 1900 struct addrinfo *ai; 1901 struct addr_ptr *addrs, addr; 1902 struct sockaddr_in *sin; 1903 int naddrs, i, j; 1904 int needsort = 0; 1905 1906 if (!sentinel) 1907 return -1; 1908 naddrs = 0; 1909 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) 1910 naddrs++; 1911 if (naddrs < 2) 1912 return 0; /* We don't need sorting. */ 1913 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) 1914 return -1; 1915 i = 0; 1916 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { 1917 sin = (struct sockaddr_in *)ai->ai_addr; 1918 for (j = 0; (unsigned)j < _res.nsort; j++) { 1919 if (_res.sort_list[j].addr.s_addr == 1920 (sin->sin_addr.s_addr & _res.sort_list[j].mask)) 1921 break; 1922 } 1923 addrs[i].ai = ai; 1924 addrs[i].aval = j; 1925 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) 1926 needsort = i; 1927 i++; 1928 } 1929 if (!needsort) { 1930 free(addrs); 1931 return 0; 1932 } 1933 1934 while (needsort < naddrs) { 1935 for (j = needsort - 1; j >= 0; j--) { 1936 if (addrs[j].aval > addrs[j+1].aval) { 1937 addr = addrs[j]; 1938 addrs[j] = addrs[j + 1]; 1939 addrs[j + 1] = addr; 1940 } else 1941 break; 1942 } 1943 needsort++; 1944 } 1945 1946 ai = sentinel; 1947 for (i = 0; i < naddrs; ++i) { 1948 ai->ai_next = addrs[i].ai; 1949 ai = ai->ai_next; 1950 } 1951 ai->ai_next = NULL; 1952 free(addrs); 1953 return 0; 1954 } 1955 #endif /*RESOLVSORT*/ 1956 1957 /*ARGSUSED*/ 1958 static int 1959 _dns_getaddrinfo(rv, cb_data, ap) 1960 void *rv; 1961 void *cb_data; 1962 va_list ap; 1963 { 1964 struct addrinfo *ai; 1965 querybuf *buf, *buf2; 1966 const char *hostname; 1967 const struct addrinfo *pai; 1968 struct addrinfo sentinel, *cur; 1969 struct res_target q, q2; 1970 1971 hostname = va_arg(ap, char *); 1972 pai = va_arg(ap, const struct addrinfo *); 1973 1974 memset(&q, 0, sizeof(q2)); 1975 memset(&q2, 0, sizeof(q2)); 1976 memset(&sentinel, 0, sizeof(sentinel)); 1977 cur = &sentinel; 1978 1979 buf = malloc(sizeof(*buf)); 1980 if (!buf) { 1981 h_errno = NETDB_INTERNAL; 1982 return NS_NOTFOUND; 1983 } 1984 buf2 = malloc(sizeof(*buf2)); 1985 if (!buf2) { 1986 free(buf); 1987 h_errno = NETDB_INTERNAL; 1988 return NS_NOTFOUND; 1989 } 1990 1991 switch (pai->ai_family) { 1992 case AF_UNSPEC: 1993 q.name = hostname; 1994 q.qclass = C_IN; 1995 q.qtype = T_A; 1996 q.answer = buf->buf; 1997 q.anslen = sizeof(buf->buf); 1998 q.next = &q2; 1999 q2.name = hostname; 2000 q2.qclass = C_IN; 2001 q2.qtype = T_AAAA; 2002 q2.answer = buf2->buf; 2003 q2.anslen = sizeof(buf2->buf); 2004 break; 2005 case AF_INET: 2006 q.name = hostname; 2007 q.qclass = C_IN; 2008 q.qtype = T_A; 2009 q.answer = buf->buf; 2010 q.anslen = sizeof(buf->buf); 2011 break; 2012 case AF_INET6: 2013 q.name = hostname; 2014 q.qclass = C_IN; 2015 q.qtype = T_AAAA; 2016 q.answer = buf->buf; 2017 q.anslen = sizeof(buf->buf); 2018 break; 2019 default: 2020 free(buf); 2021 free(buf2); 2022 return NS_UNAVAIL; 2023 } 2024 if (res_searchN(hostname, &q) < 0) { 2025 free(buf); 2026 free(buf2); 2027 return NS_NOTFOUND; 2028 } 2029 /* prefer IPv6 */ 2030 if (q.next) { 2031 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai); 2032 if (ai) { 2033 cur->ai_next = ai; 2034 while (cur && cur->ai_next) 2035 cur = cur->ai_next; 2036 } 2037 } 2038 ai = getanswer(buf, q.n, q.name, q.qtype, pai); 2039 if (ai) 2040 cur->ai_next = ai; 2041 free(buf); 2042 free(buf2); 2043 if (sentinel.ai_next == NULL) 2044 switch (h_errno) { 2045 case HOST_NOT_FOUND: 2046 return NS_NOTFOUND; 2047 case TRY_AGAIN: 2048 return NS_TRYAGAIN; 2049 default: 2050 return NS_UNAVAIL; 2051 } 2052 *((struct addrinfo **)rv) = sentinel.ai_next; 2053 return NS_SUCCESS; 2054 } 2055 2056 static void 2057 _sethtent() 2058 { 2059 if (!hostf) 2060 hostf = fopen(_PATH_HOSTS, "r" ); 2061 else 2062 rewind(hostf); 2063 } 2064 2065 static void 2066 _endhtent() 2067 { 2068 if (hostf) { 2069 (void) fclose(hostf); 2070 hostf = NULL; 2071 } 2072 } 2073 2074 static struct addrinfo * 2075 _gethtent(name, pai) 2076 const char *name; 2077 const struct addrinfo *pai; 2078 { 2079 char *p; 2080 char *cp, *tname, *cname; 2081 struct addrinfo hints, *res0, *res; 2082 int error; 2083 const char *addr; 2084 char hostbuf[8*1024]; 2085 2086 if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) 2087 return (NULL); 2088 again: 2089 if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) 2090 return (NULL); 2091 if (*p == '#') 2092 goto again; 2093 cp = strpbrk(p, "#\n"); 2094 if (cp != NULL) 2095 *cp = '\0'; 2096 if (!(cp = strpbrk(p, " \t"))) 2097 goto again; 2098 *cp++ = '\0'; 2099 addr = p; 2100 cname = NULL; 2101 /* if this is not something we're looking for, skip it. */ 2102 while (cp && *cp) { 2103 if (*cp == ' ' || *cp == '\t') { 2104 cp++; 2105 continue; 2106 } 2107 tname = cp; 2108 if (cname == NULL) 2109 cname = cp; 2110 if ((cp = strpbrk(cp, " \t")) != NULL) 2111 *cp++ = '\0'; 2112 if (strcasecmp(name, tname) == 0) 2113 goto found; 2114 } 2115 goto again; 2116 2117 found: 2118 /* we should not glob socktype/protocol here */ 2119 memset(&hints, 0, sizeof(hints)); 2120 hints.ai_family = pai->ai_family; 2121 hints.ai_socktype = SOCK_DGRAM; 2122 hints.ai_protocol = 0; 2123 hints.ai_flags = AI_NUMERICHOST; 2124 error = getaddrinfo(addr, "0", &hints, &res0); 2125 if (error) 2126 goto again; 2127 #ifdef FILTER_V4MAPPED 2128 /* XXX should check all items in the chain */ 2129 if (res0->ai_family == AF_INET6 && 2130 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { 2131 freeaddrinfo(res0); 2132 goto again; 2133 } 2134 #endif 2135 for (res = res0; res; res = res->ai_next) { 2136 /* cover it up */ 2137 res->ai_flags = pai->ai_flags; 2138 res->ai_socktype = pai->ai_socktype; 2139 res->ai_protocol = pai->ai_protocol; 2140 2141 if (pai->ai_flags & AI_CANONNAME) { 2142 if (get_canonname(pai, res, cname) != 0) { 2143 freeaddrinfo(res0); 2144 goto again; 2145 } 2146 } 2147 } 2148 return res0; 2149 } 2150 2151 /*ARGSUSED*/ 2152 static int 2153 _files_getaddrinfo(rv, cb_data, ap) 2154 void *rv; 2155 void *cb_data; 2156 va_list ap; 2157 { 2158 const char *name; 2159 const struct addrinfo *pai; 2160 struct addrinfo sentinel, *cur; 2161 struct addrinfo *p; 2162 2163 name = va_arg(ap, char *); 2164 pai = va_arg(ap, struct addrinfo *); 2165 2166 memset(&sentinel, 0, sizeof(sentinel)); 2167 cur = &sentinel; 2168 2169 THREAD_LOCK(); 2170 _sethtent(); 2171 while ((p = _gethtent(name, pai)) != NULL) { 2172 cur->ai_next = p; 2173 while (cur && cur->ai_next) 2174 cur = cur->ai_next; 2175 } 2176 _endhtent(); 2177 THREAD_UNLOCK(); 2178 2179 *((struct addrinfo **)rv) = sentinel.ai_next; 2180 if (sentinel.ai_next == NULL) 2181 return NS_NOTFOUND; 2182 return NS_SUCCESS; 2183 } 2184 2185 #ifdef YP 2186 static char *__ypdomain; 2187 2188 /*ARGSUSED*/ 2189 static struct addrinfo * 2190 _yphostent(line, pai) 2191 char *line; 2192 const struct addrinfo *pai; 2193 { 2194 struct addrinfo sentinel, *cur; 2195 struct addrinfo hints, *res, *res0; 2196 int error; 2197 char *p = line; 2198 const char *addr, *canonname; 2199 char *nextline; 2200 char *cp; 2201 2202 addr = canonname = NULL; 2203 2204 memset(&sentinel, 0, sizeof(sentinel)); 2205 cur = &sentinel; 2206 2207 nextline: 2208 /* terminate line */ 2209 cp = strchr(p, '\n'); 2210 if (cp) { 2211 *cp++ = '\0'; 2212 nextline = cp; 2213 } else 2214 nextline = NULL; 2215 2216 cp = strpbrk(p, " \t"); 2217 if (cp == NULL) { 2218 if (canonname == NULL) 2219 return (NULL); 2220 else 2221 goto done; 2222 } 2223 *cp++ = '\0'; 2224 2225 addr = p; 2226 2227 while (cp && *cp) { 2228 if (*cp == ' ' || *cp == '\t') { 2229 cp++; 2230 continue; 2231 } 2232 if (!canonname) 2233 canonname = cp; 2234 if ((cp = strpbrk(cp, " \t")) != NULL) 2235 *cp++ = '\0'; 2236 } 2237 2238 hints = *pai; 2239 hints.ai_flags = AI_NUMERICHOST; 2240 error = getaddrinfo(addr, NULL, &hints, &res0); 2241 if (error == 0) { 2242 for (res = res0; res; res = res->ai_next) { 2243 /* cover it up */ 2244 res->ai_flags = pai->ai_flags; 2245 2246 if (pai->ai_flags & AI_CANONNAME) 2247 (void)get_canonname(pai, res, canonname); 2248 } 2249 } else 2250 res0 = NULL; 2251 if (res0) { 2252 cur->ai_next = res0; 2253 while (cur && cur->ai_next) 2254 cur = cur->ai_next; 2255 } 2256 2257 if (nextline) { 2258 p = nextline; 2259 goto nextline; 2260 } 2261 2262 done: 2263 return sentinel.ai_next; 2264 } 2265 2266 /*ARGSUSED*/ 2267 static int 2268 _yp_getaddrinfo(rv, cb_data, ap) 2269 void *rv; 2270 void *cb_data; 2271 va_list ap; 2272 { 2273 struct addrinfo sentinel, *cur; 2274 struct addrinfo *ai = NULL; 2275 static char *__ypcurrent; 2276 int __ypcurrentlen, r; 2277 const char *name; 2278 const struct addrinfo *pai; 2279 2280 name = va_arg(ap, char *); 2281 pai = va_arg(ap, const struct addrinfo *); 2282 2283 memset(&sentinel, 0, sizeof(sentinel)); 2284 cur = &sentinel; 2285 2286 THREAD_LOCK(); 2287 if (!__ypdomain) { 2288 if (_yp_check(&__ypdomain) == 0) { 2289 THREAD_UNLOCK(); 2290 return NS_UNAVAIL; 2291 } 2292 } 2293 if (__ypcurrent) 2294 free(__ypcurrent); 2295 __ypcurrent = NULL; 2296 2297 /* hosts.byname is only for IPv4 (Solaris8) */ 2298 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { 2299 r = yp_match(__ypdomain, "hosts.byname", name, 2300 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 2301 if (r == 0) { 2302 struct addrinfo ai4; 2303 2304 ai4 = *pai; 2305 ai4.ai_family = AF_INET; 2306 ai = _yphostent(__ypcurrent, &ai4); 2307 if (ai) { 2308 cur->ai_next = ai; 2309 while (cur && cur->ai_next) 2310 cur = cur->ai_next; 2311 } 2312 } 2313 } 2314 2315 /* ipnodes.byname can hold both IPv4/v6 */ 2316 r = yp_match(__ypdomain, "ipnodes.byname", name, 2317 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 2318 if (r == 0) { 2319 ai = _yphostent(__ypcurrent, pai); 2320 if (ai) { 2321 cur->ai_next = ai; 2322 while (cur && cur->ai_next) 2323 cur = cur->ai_next; 2324 } 2325 } 2326 THREAD_UNLOCK(); 2327 2328 if (sentinel.ai_next == NULL) { 2329 h_errno = HOST_NOT_FOUND; 2330 return NS_NOTFOUND; 2331 } 2332 *((struct addrinfo **)rv) = sentinel.ai_next; 2333 return NS_SUCCESS; 2334 } 2335 #endif 2336 2337 /* resolver logic */ 2338 2339 extern const char *__hostalias(const char *); 2340 2341 /* 2342 * Formulate a normal query, send, and await answer. 2343 * Returned answer is placed in supplied buffer "answer". 2344 * Perform preliminary check of answer, returning success only 2345 * if no error is indicated and the answer count is nonzero. 2346 * Return the size of the response on success, -1 on error. 2347 * Error number is left in h_errno. 2348 * 2349 * Caller must parse answer and determine whether it answers the question. 2350 */ 2351 static int 2352 res_queryN(name, target) 2353 const char *name; /* domain name */ 2354 struct res_target *target; 2355 { 2356 u_char *buf; 2357 HEADER *hp; 2358 int n; 2359 struct res_target *t; 2360 int rcode; 2361 int ancount; 2362 2363 rcode = NOERROR; 2364 ancount = 0; 2365 2366 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2367 h_errno = NETDB_INTERNAL; 2368 return (-1); 2369 } 2370 2371 buf = malloc(MAXPACKET); 2372 if (!buf) { 2373 h_errno = NETDB_INTERNAL; 2374 return -1; 2375 } 2376 2377 for (t = target; t; t = t->next) { 2378 int class, type; 2379 u_char *answer; 2380 int anslen; 2381 2382 hp = (HEADER *)(void *)t->answer; 2383 hp->rcode = NOERROR; /* default */ 2384 2385 /* make it easier... */ 2386 class = t->qclass; 2387 type = t->qtype; 2388 answer = t->answer; 2389 anslen = t->anslen; 2390 #ifdef DEBUG 2391 if (_res.options & RES_DEBUG) 2392 printf(";; res_query(%s, %d, %d)\n", name, class, type); 2393 #endif 2394 2395 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, 2396 buf, MAXPACKET); 2397 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) 2398 n = res_opt(n, buf, MAXPACKET, anslen); 2399 if (n <= 0) { 2400 #ifdef DEBUG 2401 if (_res.options & RES_DEBUG) 2402 printf(";; res_query: mkquery failed\n"); 2403 #endif 2404 free(buf); 2405 h_errno = NO_RECOVERY; 2406 return (n); 2407 } 2408 n = res_send(buf, n, answer, anslen); 2409 #if 0 2410 if (n < 0) { 2411 #ifdef DEBUG 2412 if (_res.options & RES_DEBUG) 2413 printf(";; res_query: send error\n"); 2414 #endif 2415 free(buf); 2416 h_errno = TRY_AGAIN; 2417 return (n); 2418 } 2419 #endif 2420 2421 if (n < 0 || n > anslen) 2422 hp->rcode = FORMERR; /* XXX not very informative */ 2423 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { 2424 rcode = hp->rcode; /* record most recent error */ 2425 #ifdef DEBUG 2426 if (_res.options & RES_DEBUG) 2427 printf(";; rcode = %u, ancount=%u\n", hp->rcode, 2428 ntohs(hp->ancount)); 2429 #endif 2430 continue; 2431 } 2432 2433 ancount += ntohs(hp->ancount); 2434 2435 t->n = n; 2436 } 2437 2438 free(buf); 2439 2440 if (ancount == 0) { 2441 switch (rcode) { 2442 case NXDOMAIN: 2443 h_errno = HOST_NOT_FOUND; 2444 break; 2445 case SERVFAIL: 2446 h_errno = TRY_AGAIN; 2447 break; 2448 case NOERROR: 2449 h_errno = NO_DATA; 2450 break; 2451 case FORMERR: 2452 case NOTIMP: 2453 case REFUSED: 2454 default: 2455 h_errno = NO_RECOVERY; 2456 break; 2457 } 2458 return (-1); 2459 } 2460 return (ancount); 2461 } 2462 2463 /* 2464 * Formulate a normal query, send, and retrieve answer in supplied buffer. 2465 * Return the size of the response on success, -1 on error. 2466 * If enabled, implement search rules until answer or unrecoverable failure 2467 * is detected. Error code, if any, is left in h_errno. 2468 */ 2469 static int 2470 res_searchN(name, target) 2471 const char *name; /* domain name */ 2472 struct res_target *target; 2473 { 2474 const char *cp, * const *domain; 2475 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ 2476 u_int dots; 2477 int trailing_dot, ret, saved_herrno; 2478 int got_nodata = 0, got_servfail = 0, tried_as_is = 0; 2479 2480 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2481 h_errno = NETDB_INTERNAL; 2482 return (-1); 2483 } 2484 2485 errno = 0; 2486 h_errno = HOST_NOT_FOUND; /* default, if we never query */ 2487 dots = 0; 2488 for (cp = name; *cp; cp++) 2489 dots += (*cp == '.'); 2490 trailing_dot = 0; 2491 if (cp > name && *--cp == '.') 2492 trailing_dot++; 2493 2494 /* 2495 * if there aren't any dots, it could be a user-level alias 2496 */ 2497 if (!dots && (cp = __hostalias(name)) != NULL) 2498 return (res_queryN(cp, target)); 2499 2500 /* 2501 * If there are dots in the name already, let's just give it a try 2502 * 'as is'. The threshold can be set with the "ndots" option. 2503 */ 2504 saved_herrno = -1; 2505 if (dots >= _res.ndots) { 2506 ret = res_querydomainN(name, NULL, target); 2507 if (ret > 0) 2508 return (ret); 2509 saved_herrno = h_errno; 2510 tried_as_is++; 2511 } 2512 2513 /* 2514 * We do at least one level of search if 2515 * - there is no dot and RES_DEFNAME is set, or 2516 * - there is at least one dot, there is no trailing dot, 2517 * and RES_DNSRCH is set. 2518 */ 2519 if ((!dots && (_res.options & RES_DEFNAMES)) || 2520 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { 2521 int done = 0; 2522 2523 for (domain = (const char * const *)_res.dnsrch; 2524 *domain && !done; 2525 domain++) { 2526 2527 ret = res_querydomainN(name, *domain, target); 2528 if (ret > 0) 2529 return (ret); 2530 2531 /* 2532 * If no server present, give up. 2533 * If name isn't found in this domain, 2534 * keep trying higher domains in the search list 2535 * (if that's enabled). 2536 * On a NO_DATA error, keep trying, otherwise 2537 * a wildcard entry of another type could keep us 2538 * from finding this entry higher in the domain. 2539 * If we get some other error (negative answer or 2540 * server failure), then stop searching up, 2541 * but try the input name below in case it's 2542 * fully-qualified. 2543 */ 2544 if (errno == ECONNREFUSED) { 2545 h_errno = TRY_AGAIN; 2546 return (-1); 2547 } 2548 2549 switch (h_errno) { 2550 case NO_DATA: 2551 got_nodata++; 2552 /* FALLTHROUGH */ 2553 case HOST_NOT_FOUND: 2554 /* keep trying */ 2555 break; 2556 case TRY_AGAIN: 2557 if (hp->rcode == SERVFAIL) { 2558 /* try next search element, if any */ 2559 got_servfail++; 2560 break; 2561 } 2562 /* FALLTHROUGH */ 2563 default: 2564 /* anything else implies that we're done */ 2565 done++; 2566 } 2567 /* 2568 * if we got here for some reason other than DNSRCH, 2569 * we only wanted one iteration of the loop, so stop. 2570 */ 2571 if (!(_res.options & RES_DNSRCH)) 2572 done++; 2573 } 2574 } 2575 2576 /* 2577 * if we have not already tried the name "as is", do that now. 2578 * note that we do this regardless of how many dots were in the 2579 * name or whether it ends with a dot. 2580 */ 2581 if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) { 2582 ret = res_querydomainN(name, NULL, target); 2583 if (ret > 0) 2584 return (ret); 2585 } 2586 2587 /* 2588 * if we got here, we didn't satisfy the search. 2589 * if we did an initial full query, return that query's h_errno 2590 * (note that we wouldn't be here if that query had succeeded). 2591 * else if we ever got a nodata, send that back as the reason. 2592 * else send back meaningless h_errno, that being the one from 2593 * the last DNSRCH we did. 2594 */ 2595 if (saved_herrno != -1) 2596 h_errno = saved_herrno; 2597 else if (got_nodata) 2598 h_errno = NO_DATA; 2599 else if (got_servfail) 2600 h_errno = TRY_AGAIN; 2601 return (-1); 2602 } 2603 2604 /* 2605 * Perform a call on res_query on the concatenation of name and domain, 2606 * removing a trailing dot from name if domain is NULL. 2607 */ 2608 static int 2609 res_querydomainN(name, domain, target) 2610 const char *name, *domain; 2611 struct res_target *target; 2612 { 2613 char nbuf[MAXDNAME]; 2614 const char *longname = nbuf; 2615 size_t n, d; 2616 2617 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 2618 h_errno = NETDB_INTERNAL; 2619 return (-1); 2620 } 2621 #ifdef DEBUG 2622 if (_res.options & RES_DEBUG) 2623 printf(";; res_querydomain(%s, %s)\n", 2624 name, domain?domain:"<Nil>"); 2625 #endif 2626 if (domain == NULL) { 2627 /* 2628 * Check for trailing '.'; 2629 * copy without '.' if present. 2630 */ 2631 n = strlen(name); 2632 if (n >= MAXDNAME) { 2633 h_errno = NO_RECOVERY; 2634 return (-1); 2635 } 2636 if (n > 0 && name[--n] == '.') { 2637 strncpy(nbuf, name, n); 2638 nbuf[n] = '\0'; 2639 } else 2640 longname = name; 2641 } else { 2642 n = strlen(name); 2643 d = strlen(domain); 2644 if (n + d + 1 >= MAXDNAME) { 2645 h_errno = NO_RECOVERY; 2646 return (-1); 2647 } 2648 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); 2649 } 2650 return (res_queryN(longname, target)); 2651 } 2652