getaddrinfo.c revision 1.30
1 /* $NetBSD: getaddrinfo.c,v 1.30 2000/02/16 04:50:23 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 * Issues to be discussed: 34 * - Thread safe-ness must be checked. 35 * - Return values. There are nonstandard return values defined and used 36 * in the source code. This is because RFC2553 is silent about which error 37 * code must be returned for which situation. 38 * - IPv4 classful (shortened) form. RFC2553 is silent about it. XNET 5.2 39 * says to use inet_aton() to convert IPv4 numeric to binary (alows 40 * classful form as a result). 41 * current code - disallow classful form for IPv4 (due to use of inet_pton). 42 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is 43 * invalid. 44 * current code - SEGV on freeaddrinfo(NULL) 45 * Note: 46 * - We use getipnodebyname() just for thread-safeness. There's no intent 47 * to let it do PF_UNSPEC (actually we never pass PF_UNSPEC to 48 * getipnodebyname(). 49 * - The code filters out AFs that are not supported by the kernel, 50 * when globbing NULL hostname (to loopback, or wildcard). Is it the right 51 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 52 * in ai_flags? 53 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. 54 * (1) what should we do against numeric hostname (2) what should we do 55 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? 56 * non-loopback address configured? global address configured? 57 * - The code makes use of following calls when asked to resolver with 58 * ai_family = PF_UNSPEC: 59 * getipnodebyname(host, AF_INET6); 60 * getipnodebyname(host, AF_INET); 61 * This will result in the following queries if the node is configure to 62 * prefer /etc/hosts than DNS: 63 * lookup /etc/hosts for IPv6 address 64 * lookup DNS for IPv6 address 65 * lookup /etc/hosts for IPv4 address 66 * lookup DNS for IPv4 address 67 * which may not meet people's requirement. 68 * The right thing to happen is to have underlying layer which does 69 * PF_UNSPEC lookup (lookup both) and return chain of addrinfos. 70 * This would result in a bit of code duplicate with _dns_ghbyname() and 71 * friends. 72 */ 73 74 #include <sys/types.h> 75 #include <sys/param.h> 76 #include <sys/socket.h> 77 #include <net/if.h> 78 #include <netinet/in.h> 79 #include <arpa/inet.h> 80 #include <arpa/nameser.h> 81 #include <netdb.h> 82 #include <resolv.h> 83 #include <string.h> 84 #include <stdlib.h> 85 #include <stddef.h> 86 #include <ctype.h> 87 #include <unistd.h> 88 #include <stdio.h> 89 #include <errno.h> 90 91 #define SUCCESS 0 92 #define ANY 0 93 #define YES 1 94 #define NO 0 95 96 static const char in_addrany[] = { 0, 0, 0, 0 }; 97 static const char in6_addrany[] = { 98 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 99 }; 100 static const char in_loopback[] = { 127, 0, 0, 1 }; 101 static const char in6_loopback[] = { 102 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 103 }; 104 105 struct sockinet { 106 u_char si_len; 107 u_char si_family; 108 u_short si_port; 109 u_int32_t si_scope_id; 110 }; 111 112 static const struct afd { 113 int a_af; 114 int a_addrlen; 115 int a_socklen; 116 int a_off; 117 const char *a_addrany; 118 const char *a_loopback; 119 int a_scoped; 120 } afdl [] = { 121 #ifdef INET6 122 {PF_INET6, sizeof(struct in6_addr), 123 sizeof(struct sockaddr_in6), 124 offsetof(struct sockaddr_in6, sin6_addr), 125 in6_addrany, in6_loopback, 1}, 126 #endif 127 {PF_INET, sizeof(struct in_addr), 128 sizeof(struct sockaddr_in), 129 offsetof(struct sockaddr_in, sin_addr), 130 in_addrany, in_loopback, 0}, 131 {0, 0, 0, 0, NULL, NULL, 0}, 132 }; 133 134 struct explore { 135 int e_af; 136 int e_socktype; 137 int e_protocol; 138 const char *e_protostr; 139 int e_wild; 140 #define WILD_AF(ex) ((ex)->e_wild & 0x01) 141 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 142 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 143 }; 144 145 static const struct explore explore[] = { 146 #if 0 147 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 148 #endif 149 #ifdef INET6 150 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 151 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 152 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 153 #endif 154 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 155 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 156 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 157 { -1, 0, 0, NULL, 0 }, 158 }; 159 160 #ifdef INET6 161 #define PTON_MAX 16 162 #else 163 #define PTON_MAX 4 164 #endif 165 166 167 static int str_isnumber __P((const char *)); 168 static int explore_fqdn __P((const struct addrinfo *, const char *, 169 const char *, struct addrinfo **)); 170 static int explore_null __P((const struct addrinfo *, 171 const char *, struct addrinfo **)); 172 static int explore_numeric __P((const struct addrinfo *, const char *, 173 const char *, struct addrinfo **)); 174 static int explore_numeric_scope __P((const struct addrinfo *, const char *, 175 const char *, struct addrinfo **)); 176 static int get_canonname __P((const struct addrinfo *, 177 struct addrinfo *, const char *)); 178 static struct addrinfo *get_ai __P((const struct addrinfo *, 179 const struct afd *, const char *)); 180 static int get_portmatch __P((const struct addrinfo *, const char *)); 181 static int get_port __P((struct addrinfo *, const char *, int)); 182 static const struct afd *find_afd __P((int)); 183 static int addrconfig __P((const struct addrinfo *)); 184 #ifdef INET6 185 static int ip6_str2scopeid __P((char *, struct sockaddr_in6 *)); 186 #endif 187 188 static char *ai_errlist[] = { 189 "Success", 190 "Address family for hostname not supported", /* EAI_ADDRFAMILY */ 191 "Temporary failure in name resolution", /* EAI_AGAIN */ 192 "Invalid value for ai_flags", /* EAI_BADFLAGS */ 193 "Non-recoverable failure in name resolution", /* EAI_FAIL */ 194 "ai_family not supported", /* EAI_FAMILY */ 195 "Memory allocation failure", /* EAI_MEMORY */ 196 "No address associated with hostname", /* EAI_NODATA */ 197 "hostname nor servname provided, or not known", /* EAI_NONAME */ 198 "servname not supported for ai_socktype", /* EAI_SERVICE */ 199 "ai_socktype not supported", /* EAI_SOCKTYPE */ 200 "System error returned in errno", /* EAI_SYSTEM */ 201 "Invalid value for hints", /* EAI_BADHINTS */ 202 "Resolved protocol is unknown", /* EAI_PROTOCOL */ 203 "Unknown error", /* EAI_MAX */ 204 }; 205 206 /* XXX macros that make external reference is BAD. */ 207 208 #define GET_AI(ai, afd, addr) \ 209 do { \ 210 /* external reference: pai, error, and label free */ \ 211 (ai) = get_ai(pai, (afd), (addr)); \ 212 if ((ai) == NULL) { \ 213 error = EAI_MEMORY; \ 214 goto free; \ 215 } \ 216 } while (/*CONSTCOND*/0) 217 218 #define GET_PORT(ai, serv) \ 219 do { \ 220 /* external reference: error and label free */ \ 221 error = get_port((ai), (serv), 0); \ 222 if (error != 0) \ 223 goto free; \ 224 } while (/*CONSTCOND*/0) 225 226 #define GET_CANONNAME(ai, str) \ 227 do { \ 228 /* external reference: pai, error and label free */ \ 229 error = get_canonname(pai, (ai), (str)); \ 230 if (error != 0) \ 231 goto free; \ 232 } while (/*CONSTCOND*/0) 233 234 #define ERR(err) \ 235 do { \ 236 /* external reference: error, and label bad */ \ 237 error = (err); \ 238 goto bad; \ 239 } while (/*CONSTCOND*/0) 240 241 #define MATCH_FAMILY(x, y, w) \ 242 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 243 #define MATCH(x, y, w) \ 244 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 245 246 char * 247 gai_strerror(ecode) 248 int ecode; 249 { 250 if (ecode < 0 || ecode > EAI_MAX) 251 ecode = EAI_MAX; 252 return ai_errlist[ecode]; 253 } 254 255 void 256 freeaddrinfo(ai) 257 struct addrinfo *ai; 258 { 259 struct addrinfo *next; 260 261 do { 262 next = ai->ai_next; 263 if (ai->ai_canonname) 264 free(ai->ai_canonname); 265 /* no need to free(ai->ai_addr) */ 266 free(ai); 267 ai = next; 268 } while (ai); 269 } 270 271 static int 272 str_isnumber(p) 273 const char *p; 274 { 275 const char *q = (const char *)p; 276 while (*q) { 277 if (!isdigit(*q)) 278 return NO; 279 q++; 280 } 281 return YES; 282 } 283 284 int 285 getaddrinfo(hostname, servname, hints, res) 286 const char *hostname, *servname; 287 const struct addrinfo *hints; 288 struct addrinfo **res; 289 { 290 struct addrinfo sentinel; 291 struct addrinfo *cur; 292 int error = 0; 293 struct addrinfo ai; 294 struct addrinfo ai0; 295 struct addrinfo *pai; 296 const struct afd *afd; 297 const struct explore *ex; 298 299 sentinel.ai_next = NULL; 300 cur = &sentinel; 301 pai = &ai; 302 pai->ai_flags = 0; 303 pai->ai_family = PF_UNSPEC; 304 pai->ai_socktype = ANY; 305 pai->ai_protocol = ANY; 306 pai->ai_addrlen = 0; 307 pai->ai_canonname = NULL; 308 pai->ai_addr = NULL; 309 pai->ai_next = NULL; 310 311 if (hostname == NULL && servname == NULL) 312 return EAI_NONAME; 313 if (hints) { 314 /* error check for hints */ 315 if (hints->ai_addrlen || hints->ai_canonname || 316 hints->ai_addr || hints->ai_next) 317 ERR(EAI_BADHINTS); /* xxx */ 318 if (hints->ai_flags & ~AI_MASK) 319 ERR(EAI_BADFLAGS); 320 switch (hints->ai_family) { 321 case PF_UNSPEC: 322 case PF_INET: 323 #ifdef INET6 324 case PF_INET6: 325 #endif 326 break; 327 default: 328 ERR(EAI_FAMILY); 329 } 330 memcpy(pai, hints, sizeof(*pai)); 331 332 /* 333 * if both socktype/protocol are specified, check if they 334 * are meaningful combination. 335 */ 336 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 337 for (ex = explore; ex->e_af >= 0; ex++) { 338 if (pai->ai_family != ex->e_af) 339 continue; 340 if (ex->e_socktype == ANY) 341 continue; 342 if (ex->e_protocol == ANY) 343 continue; 344 if (pai->ai_socktype == ex->e_socktype 345 && pai->ai_protocol != ex->e_protocol) { 346 ERR(EAI_BADHINTS); 347 } 348 } 349 } 350 } 351 352 /* 353 * check for special cases. (1) numeric servname is disallowed if 354 * socktype/protocol are left unspecified. (2) servname is disallowed 355 * for raw and other inet{,6} sockets. 356 */ 357 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 358 #ifdef PF_INET6 359 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) 360 #endif 361 ) { 362 ai0 = *pai; /* backup *pai */ 363 364 if (pai->ai_family == PF_UNSPEC) { 365 #ifdef PF_INET6 366 pai->ai_family = PF_INET6; 367 #else 368 pai->ai_family = PF_INET; 369 #endif 370 } 371 error = get_portmatch(pai, servname); 372 if (error) 373 ERR(error); 374 375 *pai = ai0; 376 } 377 378 ai0 = *pai; 379 380 /* NULL hostname, or numeric hostname */ 381 for (ex = explore; ex->e_af >= 0; ex++) { 382 *pai = ai0; 383 384 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 385 continue; 386 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 387 continue; 388 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 389 continue; 390 391 if (pai->ai_family == PF_UNSPEC) 392 pai->ai_family = ex->e_af; 393 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 394 pai->ai_socktype = ex->e_socktype; 395 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 396 pai->ai_protocol = ex->e_protocol; 397 398 if (hostname == NULL) 399 error = explore_null(pai, servname, &cur->ai_next); 400 else 401 error = explore_numeric_scope(pai, hostname, servname, &cur->ai_next); 402 403 if (error) 404 goto free; 405 406 while (cur && cur->ai_next) 407 cur = cur->ai_next; 408 } 409 410 /* 411 * XXX 412 * If numreic representation of AF1 can be interpreted as FQDN 413 * representation of AF2, we need to think again about the code below. 414 */ 415 if (sentinel.ai_next) 416 goto good; 417 418 if (pai->ai_flags & AI_NUMERICHOST) 419 ERR(EAI_NONAME); 420 if (hostname == NULL) 421 ERR(EAI_NONAME); 422 423 /* 424 * hostname as alphabetical name. 425 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 426 * outer loop by AFs. 427 */ 428 for (afd = afdl; afd->a_af; afd++) { 429 *pai = ai0; 430 431 if (!MATCH_FAMILY(pai->ai_family, afd->a_af, 1)) 432 continue; 433 434 for (ex = explore; ex->e_af >= 0; ex++) { 435 *pai = ai0; 436 437 if (pai->ai_family == PF_UNSPEC) 438 pai->ai_family = afd->a_af; 439 440 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 441 continue; 442 if (!MATCH(pai->ai_socktype, ex->e_socktype, 443 WILD_SOCKTYPE(ex))) { 444 continue; 445 } 446 if (!MATCH(pai->ai_protocol, ex->e_protocol, 447 WILD_PROTOCOL(ex))) { 448 continue; 449 } 450 451 if (pai->ai_family == PF_UNSPEC) 452 pai->ai_family = ex->e_af; 453 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 454 pai->ai_socktype = ex->e_socktype; 455 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 456 pai->ai_protocol = ex->e_protocol; 457 458 error = explore_fqdn(pai, hostname, servname, 459 &cur->ai_next); 460 461 while (cur && cur->ai_next) 462 cur = cur->ai_next; 463 } 464 } 465 466 /* XXX */ 467 if (sentinel.ai_next) 468 error = 0; 469 470 if (error) 471 goto free; 472 if (error == 0) { 473 if (sentinel.ai_next) { 474 good: 475 *res = sentinel.ai_next; 476 return SUCCESS; 477 } else 478 error = EAI_FAIL; 479 } 480 free: 481 bad: 482 if (sentinel.ai_next) 483 freeaddrinfo(sentinel.ai_next); 484 *res = NULL; 485 return error; 486 } 487 488 /* 489 * FQDN hostname, DNS lookup 490 */ 491 static int 492 explore_fqdn(pai, hostname, servname, res) 493 const struct addrinfo *pai; 494 const char *hostname; 495 const char *servname; 496 struct addrinfo **res; 497 { 498 struct hostent *hp; 499 int h_error; 500 int af; 501 char **aplist = NULL, *apbuf = NULL; 502 char *ap; 503 struct addrinfo sentinel, *cur; 504 int i; 505 int naddrs; 506 const struct afd *afd; 507 int error = 0; 508 509 *res = NULL; 510 sentinel.ai_next = NULL; 511 cur = &sentinel; 512 513 /* 514 * If AI_ADDRCONFIG is specified, check if we are expected to 515 * return the address family or not. 516 */ 517 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(pai)) 518 return 0; 519 520 /* 521 * if the servname does not match socktype/protocol, ignore it. 522 */ 523 if (get_portmatch(pai, servname) != 0) 524 return 0; 525 526 afd = find_afd(pai->ai_family); 527 528 hp = gethostbyname2(hostname, pai->ai_family); 529 h_error = h_errno; 530 531 if (hp == NULL) { 532 switch (h_error) { 533 case HOST_NOT_FOUND: 534 case NO_DATA: 535 error = EAI_NODATA; 536 break; 537 case TRY_AGAIN: 538 error = EAI_AGAIN; 539 break; 540 case NO_RECOVERY: 541 case NETDB_INTERNAL: 542 default: 543 error = EAI_FAIL; 544 break; 545 } 546 } else if ((hp->h_name == NULL) || (hp->h_name[0] == 0) 547 || (hp->h_addr_list[0] == NULL)) { 548 hp = NULL; 549 error = EAI_FAIL; 550 } 551 552 if (hp == NULL) 553 goto free; 554 555 /* 556 * hp will be overwritten if we use gethostbyname2(). 557 * always deep copy for simplification. 558 */ 559 for (naddrs = 0; hp->h_addr_list[naddrs] != NULL; naddrs++) 560 ; 561 naddrs++; 562 aplist = (char **)malloc(sizeof(aplist[0]) * naddrs); 563 apbuf = (char *)malloc((size_t)hp->h_length * naddrs); 564 if (aplist == NULL || apbuf == NULL) { 565 error = EAI_MEMORY; 566 goto free; 567 } 568 memset(aplist, 0, sizeof(aplist[0]) * naddrs); 569 for (i = 0; i < naddrs; i++) { 570 if (hp->h_addr_list[i] == NULL) { 571 aplist[i] = NULL; 572 continue; 573 } 574 memcpy(&apbuf[i * hp->h_length], hp->h_addr_list[i], 575 (size_t)hp->h_length); 576 aplist[i] = &apbuf[i * hp->h_length]; 577 } 578 579 for (i = 0; aplist[i] != NULL; i++) { 580 af = hp->h_addrtype; 581 ap = aplist[i]; 582 #ifdef AF_INET6 583 if (af == AF_INET6 584 && IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ap)) { 585 af = AF_INET; 586 ap = ap + sizeof(struct in6_addr) 587 - sizeof(struct in_addr); 588 } 589 #endif 590 591 if (af != pai->ai_family) 592 continue; 593 594 GET_AI(cur->ai_next, afd, ap); 595 GET_PORT(cur->ai_next, servname); 596 if ((pai->ai_flags & AI_CANONNAME) != 0) { 597 /* 598 * RFC2553 says that ai_canonname will be set only for 599 * the first element. we do it for all the elements, 600 * just for convenience. 601 */ 602 GET_CANONNAME(cur->ai_next, hp->h_name); 603 } 604 605 while (cur && cur->ai_next) 606 cur = cur->ai_next; 607 } 608 609 *res = sentinel.ai_next; 610 return 0; 611 612 free: 613 if (aplist) 614 free(aplist); 615 if (apbuf) 616 free(apbuf); 617 if (sentinel.ai_next) 618 freeaddrinfo(sentinel.ai_next); 619 return error; 620 } 621 622 /* 623 * hostname == NULL. 624 * passive socket -> anyaddr (0.0.0.0 or ::) 625 * non-passive socket -> localhost (127.0.0.1 or ::1) 626 */ 627 static int 628 explore_null(pai, servname, res) 629 const struct addrinfo *pai; 630 const char *servname; 631 struct addrinfo **res; 632 { 633 int s; 634 const struct afd *afd; 635 struct addrinfo *cur; 636 struct addrinfo sentinel; 637 int error; 638 639 *res = NULL; 640 sentinel.ai_next = NULL; 641 cur = &sentinel; 642 643 /* 644 * filter out AFs that are not supported by the kernel 645 * XXX errno? 646 */ 647 s = socket(pai->ai_family, SOCK_DGRAM, 0); 648 if (s < 0) { 649 if (errno != EMFILE) 650 return 0; 651 } else 652 close(s); 653 654 /* 655 * if the servname does not match socktype/protocol, ignore it. 656 */ 657 if (get_portmatch(pai, servname) != 0) 658 return 0; 659 660 afd = find_afd(pai->ai_family); 661 662 if (pai->ai_flags & AI_PASSIVE) { 663 GET_AI(cur->ai_next, afd, afd->a_addrany); 664 /* xxx meaningless? 665 * GET_CANONNAME(cur->ai_next, "anyaddr"); 666 */ 667 GET_PORT(cur->ai_next, servname); 668 } else { 669 GET_AI(cur->ai_next, afd, afd->a_loopback); 670 /* xxx meaningless? 671 * GET_CANONNAME(cur->ai_next, "localhost"); 672 */ 673 GET_PORT(cur->ai_next, servname); 674 } 675 cur = cur->ai_next; 676 677 *res = sentinel.ai_next; 678 return 0; 679 680 free: 681 if (sentinel.ai_next) 682 freeaddrinfo(sentinel.ai_next); 683 return error; 684 } 685 686 /* 687 * numeric hostname 688 */ 689 static int 690 explore_numeric(pai, hostname, servname, res) 691 const struct addrinfo *pai; 692 const char *hostname; 693 const char *servname; 694 struct addrinfo **res; 695 { 696 const struct afd *afd; 697 struct addrinfo *cur; 698 struct addrinfo sentinel; 699 int error; 700 char pton[PTON_MAX]; 701 int flags; 702 703 *res = NULL; 704 sentinel.ai_next = NULL; 705 cur = &sentinel; 706 707 /* 708 * if the servname does not match socktype/protocol, ignore it. 709 */ 710 if (get_portmatch(pai, servname) != 0) 711 return 0; 712 713 afd = find_afd(pai->ai_family); 714 flags = pai->ai_flags; 715 716 switch (afd->a_af) { 717 #if 0 /*X/Open spec*/ 718 case AF_INET: 719 if (inet_aton(hostname, (struct in_addr *)pton) == 1) { 720 if (pai->ai_family == afd->a_af || 721 pai->ai_family == PF_UNSPEC /*?*/) { 722 GET_AI(cur->ai_next, afd, pton); 723 GET_PORT(cur->ai_next, servname); 724 while (cur && cur->ai_next) 725 cur = cur->ai_next; 726 } else 727 ERR(EAI_FAMILY); /*xxx*/ 728 } 729 break; 730 #endif 731 default: 732 if (inet_pton(afd->a_af, hostname, pton) == 1) { 733 if (pai->ai_family == afd->a_af || 734 pai->ai_family == PF_UNSPEC /*?*/) { 735 GET_AI(cur->ai_next, afd, pton); 736 GET_PORT(cur->ai_next, servname); 737 while (cur && cur->ai_next) 738 cur = cur->ai_next; 739 } else 740 ERR(EAI_FAMILY); /*xxx*/ 741 } 742 break; 743 } 744 745 *res = sentinel.ai_next; 746 return 0; 747 748 free: 749 bad: 750 if (sentinel.ai_next) 751 freeaddrinfo(sentinel.ai_next); 752 return error; 753 } 754 755 /* 756 * numeric hostname with scope 757 */ 758 static int 759 explore_numeric_scope(pai, hostname, servname, res) 760 const struct addrinfo *pai; 761 const char *hostname; 762 const char *servname; 763 struct addrinfo **res; 764 { 765 #if !defined(SCOPE_DELIMITER) || !defined(INET6) 766 return explore_numeric(pai, hostname, servname, res); 767 #else 768 const struct afd *afd; 769 struct addrinfo *cur; 770 int error; 771 char *cp, *hostname2 = NULL, *scope, *addr; 772 struct sockaddr_in6 *sin6; 773 774 /* 775 * if the servname does not match socktype/protocol, ignore it. 776 */ 777 if (get_portmatch(pai, servname) != 0) 778 return 0; 779 780 afd = find_afd(pai->ai_family); 781 if (!afd->a_scoped) 782 return explore_numeric(pai, hostname, servname, res); 783 784 cp = strchr(hostname, SCOPE_DELIMITER); 785 if (cp == NULL) 786 return explore_numeric(pai, hostname, servname, res); 787 788 #if 1 789 /* 790 * Handle special case of <scope id><delimiter><scoped_address> 791 */ 792 hostname2 = strdup(hostname); 793 if (hostname2 == NULL) 794 return EAI_MEMORY; 795 /* terminate at the delimiter */ 796 hostname2[cp - hostname] = '\0'; 797 scope = hostname2; 798 addr = cp + 1; 799 #else 800 /* 801 * Handle special case of <scoped_address><delimiter><scope id> 802 */ 803 hostname2 = strdup(hostname); 804 if (hostname2 == NULL) 805 return EAI_MEMORY; 806 /* terminate at the delimiter */ 807 hostname2[cp - hostname] = '\0'; 808 addr = hostname2; 809 scope = cp + 1; 810 #endif 811 812 error = explore_numeric(pai, addr, servname, res); 813 if (error == 0) { 814 int scopeid; 815 816 for (cur = *res; cur; cur = cur->ai_next) { 817 if (cur->ai_family != AF_INET6) 818 continue; 819 sin6 = (struct sockaddr_in6 *)cur->ai_addr; 820 if ((scopeid = ip6_str2scopeid(scope, sin6)) == -1) { 821 free(hostname2); 822 return(EAI_NONAME); /* XXX: is return OK? */ 823 } 824 sin6->sin6_scope_id = scopeid; 825 } 826 } 827 828 free(hostname2); 829 830 return error; 831 #endif 832 } 833 834 static int 835 get_canonname(pai, ai, str) 836 const struct addrinfo *pai; 837 struct addrinfo *ai; 838 const char *str; 839 { 840 if ((pai->ai_flags & AI_CANONNAME) != 0) { 841 ai->ai_canonname = (char *)malloc(strlen(str) + 1); 842 if (ai->ai_canonname == NULL) 843 return EAI_MEMORY; 844 strcpy(ai->ai_canonname, str); 845 } 846 return 0; 847 } 848 849 static struct addrinfo * 850 get_ai(pai, afd, addr) 851 const struct addrinfo *pai; 852 const struct afd *afd; 853 const char *addr; 854 { 855 char *p; 856 struct addrinfo *ai; 857 858 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 859 + (afd->a_socklen)); 860 if (ai == NULL) 861 return NULL; 862 863 memcpy(ai, pai, sizeof(struct addrinfo)); 864 ai->ai_addr = (struct sockaddr *)(ai + 1); 865 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 866 ai->ai_addr->sa_len = afd->a_socklen; 867 ai->ai_addrlen = afd->a_socklen; 868 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 869 p = (char *)(ai->ai_addr); 870 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 871 return ai; 872 } 873 874 static int 875 get_portmatch(ai, servname) 876 const struct addrinfo *ai; 877 const char *servname; 878 { 879 880 /* get_port does not touch first argument. when matchonly == 1. */ 881 return get_port((struct addrinfo *)ai, servname, 1); 882 } 883 884 static int 885 get_port(ai, servname, matchonly) 886 struct addrinfo *ai; 887 const char *servname; 888 int matchonly; 889 { 890 const char *proto; 891 struct servent *sp; 892 int port; 893 int allownumeric; 894 895 if (servname == NULL) 896 return 0; 897 switch (ai->ai_family) { 898 case AF_INET: 899 #ifdef AF_INET6 900 case AF_INET6: 901 #endif 902 break; 903 default: 904 return 0; 905 } 906 907 switch (ai->ai_socktype) { 908 case SOCK_RAW: 909 return EAI_SERVICE; 910 case SOCK_DGRAM: 911 case SOCK_STREAM: 912 allownumeric = 1; 913 break; 914 case ANY: 915 allownumeric = 0; 916 break; 917 default: 918 return EAI_SOCKTYPE; 919 } 920 921 if (str_isnumber(servname)) { 922 if (!allownumeric) 923 return EAI_SERVICE; 924 port = htons(atoi(servname)); 925 if (port < 0 || port > 65535) 926 return EAI_SERVICE; 927 } else { 928 switch (ai->ai_socktype) { 929 case SOCK_DGRAM: 930 proto = "udp"; 931 break; 932 case SOCK_STREAM: 933 proto = "tcp"; 934 break; 935 default: 936 proto = NULL; 937 break; 938 } 939 940 if ((sp = getservbyname(servname, proto)) == NULL) 941 return EAI_SERVICE; 942 port = sp->s_port; 943 } 944 945 if (!matchonly) { 946 switch (ai->ai_family) { 947 case AF_INET: 948 ((struct sockaddr_in *)ai->ai_addr)->sin_port = port; 949 break; 950 #ifdef INET6 951 case AF_INET6: 952 ((struct sockaddr_in6 *)ai->ai_addr)->sin6_port = port; 953 break; 954 #endif 955 } 956 } 957 958 return 0; 959 } 960 961 static const struct afd * 962 find_afd(af) 963 int af; 964 { 965 const struct afd *afd; 966 967 if (af == PF_UNSPEC) 968 return NULL; 969 for (afd = afdl; afd->a_af; afd++) { 970 if (afd->a_af == af) 971 return afd; 972 } 973 return NULL; 974 } 975 976 /* 977 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend 978 * will take care of it. 979 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure 980 * if the code is right or not. 981 */ 982 static int 983 addrconfig(pai) 984 const struct addrinfo *pai; 985 { 986 int s; 987 988 /* XXX errno */ 989 s = socket(pai->ai_family, SOCK_DGRAM, 0); 990 if (s < 0) 991 return 0; 992 close(s); 993 return 1; 994 } 995 996 #ifdef INET6 997 /* convert a string to a scope identifier. XXX: IPv6 specific */ 998 static int 999 ip6_str2scopeid(scope, sin6) 1000 char *scope; 1001 struct sockaddr_in6 *sin6; 1002 { 1003 int scopeid; 1004 struct in6_addr *a6 = &sin6->sin6_addr; 1005 char *ep; 1006 1007 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { 1008 /* 1009 * We currently assume a one-to-one mapping between links 1010 * and interfaces, so we simply use interface indices for 1011 * like-local scopes. 1012 */ 1013 scopeid = if_nametoindex(scope); 1014 if (scopeid == 0) 1015 goto trynumeric; 1016 return(scopeid); 1017 } 1018 1019 /* still unclear about literal, allow numeric only - placeholder */ 1020 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) 1021 goto trynumeric; 1022 if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) 1023 goto trynumeric; 1024 else 1025 goto trynumeric; /* global */ 1026 1027 /* try to convert to a numeric id as a last resort */ 1028 trynumeric: 1029 scopeid = (int)strtoul(scope, &ep, 10); 1030 if (*ep == '\0') 1031 return scopeid; 1032 else 1033 return -1; 1034 } 1035 #endif 1036
Indexes created Tue Sep 30 11:09:46 GMT 2025