getaddrinfo.c revision 1.20
1 /* $NetBSD: getaddrinfo.c,v 1.20 2000/01/22 23:54:20 mycroft 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 * Note: 41 * - We use getipnodebyname() just for thread-safeness. There's no intent 42 * to let it do PF_UNSPEC (actually we never pass PF_UNSPEC to 43 * getipnodebyname(). 44 * - The code filters out AFs that are not supported by the kernel, 45 * when resolving FQDNs and globbing NULL hostname. Is it the right 46 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG 47 * in ai_flags? 48 */ 49 50 #include <sys/types.h> 51 #include <sys/param.h> 52 #include <sys/socket.h> 53 #include <net/if.h> 54 #include <netinet/in.h> 55 #include <arpa/inet.h> 56 #include <arpa/nameser.h> 57 #include <netdb.h> 58 #include <resolv.h> 59 #include <string.h> 60 #include <stdlib.h> 61 #include <stddef.h> 62 #include <ctype.h> 63 #include <unistd.h> 64 #include <stdio.h> 65 #include <errno.h> 66 67 #define SUCCESS 0 68 #define ANY 0 69 #define YES 1 70 #define NO 0 71 72 #ifdef FAITH 73 static int translate = NO; 74 static struct in6_addr faith_prefix = IN6ADDR_ANY_INIT; 75 #endif 76 77 static const char in_addrany[] = { 0, 0, 0, 0 }; 78 static const char in6_addrany[] = { 79 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 80 }; 81 static const char in_loopback[] = { 127, 0, 0, 1 }; 82 static const char in6_loopback[] = { 83 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 84 }; 85 86 struct sockinet { 87 u_char si_len; 88 u_char si_family; 89 u_short si_port; 90 u_int32_t si_scope_id; 91 }; 92 93 static const struct afd { 94 int a_af; 95 int a_addrlen; 96 int a_socklen; 97 int a_off; 98 const char *a_addrany; 99 const char *a_loopback; 100 int a_scoped; 101 } afdl [] = { 102 #ifdef INET6 103 {PF_INET6, sizeof(struct in6_addr), 104 sizeof(struct sockaddr_in6), 105 offsetof(struct sockaddr_in6, sin6_addr), 106 in6_addrany, in6_loopback, 1}, 107 #endif 108 {PF_INET, sizeof(struct in_addr), 109 sizeof(struct sockaddr_in), 110 offsetof(struct sockaddr_in, sin_addr), 111 in_addrany, in_loopback, 0}, 112 {0, 0, 0, 0, NULL, NULL, 0}, 113 }; 114 115 struct explore { 116 int e_af; 117 int e_socktype; 118 int e_protocol; 119 const char *e_protostr; 120 int e_wild; 121 #define WILD_AF(ex) ((ex)->e_wild & 0x01) 122 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) 123 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) 124 }; 125 126 static const struct explore explore[] = { 127 #if 0 128 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, 129 #endif 130 #ifdef INET6 131 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 132 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 133 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, 134 #endif 135 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, 136 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, 137 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, 138 { -1, 0, 0, NULL, 0 }, 139 }; 140 141 #ifdef INET6 142 #define PTON_MAX 16 143 #else 144 #define PTON_MAX 4 145 #endif 146 147 148 static int str_isnumber __P((const char *)); 149 static int explore_fqdn __P((const struct addrinfo *, const char *, 150 const char *, struct addrinfo **)); 151 static int explore_null __P((const struct addrinfo *, 152 const char *, struct addrinfo **)); 153 static int explore_numeric __P((const struct addrinfo *, const char *, 154 const char *, struct addrinfo **)); 155 static int explore_numeric_scope __P((const struct addrinfo *, const char *, 156 const char *, struct addrinfo **)); 157 static int get_name __P((const char *, const struct afd *, struct addrinfo **, 158 char *, const struct addrinfo *, const char *)); 159 static int get_canonname __P((const struct addrinfo *, 160 struct addrinfo *, const char *)); 161 static struct addrinfo *get_ai __P((const struct addrinfo *, 162 const struct afd *, const char *)); 163 static int get_portmatch __P((const struct addrinfo *, const char *)); 164 static int get_port __P((struct addrinfo *, const char *, int)); 165 static const struct afd *find_afd __P((int)); 166 167 static char *ai_errlist[] = { 168 "Success", 169 "Address family for hostname not supported", /* EAI_ADDRFAMILY */ 170 "Temporary failure in name resolution", /* EAI_AGAIN */ 171 "Invalid value for ai_flags", /* EAI_BADFLAGS */ 172 "Non-recoverable failure in name resolution", /* EAI_FAIL */ 173 "ai_family not supported", /* EAI_FAMILY */ 174 "Memory allocation failure", /* EAI_MEMORY */ 175 "No address associated with hostname", /* EAI_NODATA */ 176 "hostname nor servname provided, or not known", /* EAI_NONAME */ 177 "servname not supported for ai_socktype", /* EAI_SERVICE */ 178 "ai_socktype not supported", /* EAI_SOCKTYPE */ 179 "System error returned in errno", /* EAI_SYSTEM */ 180 "Invalid value for hints", /* EAI_BADHINTS */ 181 "Resolved protocol is unknown", /* EAI_PROTOCOL */ 182 "Unknown error", /* EAI_MAX */ 183 }; 184 185 /* XXX macros that make external reference is BAD. */ 186 187 #define GET_AI(ai, afd, addr) \ 188 do { \ 189 /* external reference: pai, error, and label free */ \ 190 (ai) = get_ai(pai, (afd), (addr)); \ 191 if ((ai) == NULL) { \ 192 error = EAI_MEMORY; \ 193 goto free; \ 194 } \ 195 } while (/*CONSTCOND*/0) 196 197 #define GET_PORT(ai, serv) \ 198 do { \ 199 /* external reference: error and label free */ \ 200 error = get_port((ai), (serv), 0); \ 201 if (error != 0) \ 202 goto free; \ 203 } while (/*CONSTCOND*/0) 204 205 #define GET_CANONNAME(ai, str) \ 206 do { \ 207 /* external reference: pai, error and label free */ \ 208 error = get_canonname(pai, (ai), (str)); \ 209 if (error != 0) \ 210 goto free; \ 211 } while (/*CONSTCOND*/0) 212 213 #define ERR(err) \ 214 do { \ 215 /* external reference: error, and label bad */ \ 216 error = (err); \ 217 goto bad; \ 218 } while (/*CONSTCOND*/0) 219 220 #define MATCH_FAMILY(x, y, w) \ 221 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 222 #define MATCH(x, y, w) \ 223 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) 224 225 char * 226 gai_strerror(ecode) 227 int ecode; 228 { 229 if (ecode < 0 || ecode > EAI_MAX) 230 ecode = EAI_MAX; 231 return ai_errlist[ecode]; 232 } 233 234 void 235 freeaddrinfo(ai) 236 struct addrinfo *ai; 237 { 238 struct addrinfo *next; 239 240 do { 241 next = ai->ai_next; 242 if (ai->ai_canonname) 243 free(ai->ai_canonname); 244 /* no need to free(ai->ai_addr) */ 245 free(ai); 246 } while ((ai = next) != NULL); 247 } 248 249 static int 250 str_isnumber(p) 251 const char *p; 252 { 253 const char *q = (const char *)p; 254 while (*q) { 255 if (!isdigit(*q)) 256 return NO; 257 q++; 258 } 259 return YES; 260 } 261 262 int 263 getaddrinfo(hostname, servname, hints, res) 264 const char *hostname, *servname; 265 const struct addrinfo *hints; 266 struct addrinfo **res; 267 { 268 struct addrinfo sentinel; 269 struct addrinfo *cur; 270 int error = 0; 271 struct addrinfo ai; 272 struct addrinfo ai0; 273 struct addrinfo *pai; 274 const struct afd *afd; 275 const struct explore *ex; 276 277 #ifdef FAITH 278 static int firsttime = 1; 279 280 if (firsttime) { 281 /* translator hack */ 282 char *q = getenv("GAI"); 283 if (q && inet_pton(AF_INET6, q, &faith_prefix) == 1) 284 translate = YES; 285 firsttime = 0; 286 } 287 #endif 288 289 sentinel.ai_next = NULL; 290 cur = &sentinel; 291 pai = &ai; 292 pai->ai_flags = 0; 293 pai->ai_family = PF_UNSPEC; 294 pai->ai_socktype = ANY; 295 pai->ai_protocol = ANY; 296 pai->ai_addrlen = 0; 297 pai->ai_canonname = NULL; 298 pai->ai_addr = NULL; 299 pai->ai_next = NULL; 300 301 if (hostname == NULL && servname == NULL) 302 return EAI_NONAME; 303 if (hints) { 304 /* error check for hints */ 305 if (hints->ai_addrlen || hints->ai_canonname || 306 hints->ai_addr || hints->ai_next) 307 ERR(EAI_BADHINTS); /* xxx */ 308 if (hints->ai_flags & ~AI_MASK) 309 ERR(EAI_BADFLAGS); 310 switch (hints->ai_family) { 311 case PF_UNSPEC: 312 case PF_INET: 313 #ifdef INET6 314 case PF_INET6: 315 #endif 316 break; 317 default: 318 ERR(EAI_FAMILY); 319 } 320 memcpy(pai, hints, sizeof(*pai)); 321 322 /* 323 * if both socktype/protocol are specified, check if they 324 * are meaningful combination. 325 */ 326 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { 327 for (ex = explore; ex->e_af >= 0; ex++) { 328 if (pai->ai_family != ex->e_af) 329 continue; 330 if (ex->e_socktype == ANY) 331 continue; 332 if (ex->e_protocol == ANY) 333 continue; 334 if (pai->ai_socktype == ex->e_socktype 335 && pai->ai_protocol != ex->e_protocol) { 336 ERR(EAI_BADHINTS); 337 } 338 } 339 } 340 } 341 342 /* 343 * check for special cases. (1) numeric servname is disallowed if 344 * socktype/protocol are left unspecified. (2) servname is disallowed 345 * for raw and other inet{,6} sockets. 346 */ 347 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) 348 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1)) { 349 if (pai->ai_family == PF_UNSPEC) 350 pai->ai_family = PF_INET6; 351 error = get_portmatch(pai, servname); 352 if (error) 353 ERR(error); 354 } 355 356 ai0 = *pai; 357 358 /* NULL hostname, or numeric hostname */ 359 for (ex = explore; ex->e_af >= 0; ex++) { 360 *pai = ai0; 361 362 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 363 continue; 364 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 365 continue; 366 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 367 continue; 368 369 if (pai->ai_family == PF_UNSPEC) 370 pai->ai_family = ex->e_af; 371 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 372 pai->ai_socktype = ex->e_socktype; 373 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 374 pai->ai_protocol = ex->e_protocol; 375 376 if (hostname == NULL) 377 error = explore_null(pai, servname, &cur->ai_next); 378 else 379 error = explore_numeric_scope(pai, hostname, servname, &cur->ai_next); 380 381 if (error) 382 goto free; 383 384 while (cur && cur->ai_next) 385 cur = cur->ai_next; 386 } 387 388 /* 389 * XXX 390 * If numreic representation of AF1 can be interpreted as FQDN 391 * representation of AF2, we need to think again about the code below. 392 */ 393 if (sentinel.ai_next) 394 goto good; 395 396 if (pai->ai_flags & AI_NUMERICHOST) 397 ERR(EAI_NONAME); 398 if (hostname == NULL) 399 ERR(EAI_NONAME); 400 401 /* 402 * hostname as alphabetical name. 403 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 404 * outer loop by AFs. 405 */ 406 for (afd = afdl; afd->a_af; afd++) { 407 *pai = ai0; 408 409 if (!MATCH_FAMILY(pai->ai_family, afd->a_af, 1)) 410 continue; 411 412 for (ex = explore; ex->e_af >= 0; ex++) { 413 *pai = ai0; 414 415 if (pai->ai_family == PF_UNSPEC) 416 pai->ai_family = afd->a_af; 417 418 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 419 continue; 420 if (!MATCH(pai->ai_socktype, ex->e_socktype, 421 WILD_SOCKTYPE(ex))) { 422 continue; 423 } 424 if (!MATCH(pai->ai_protocol, ex->e_protocol, 425 WILD_PROTOCOL(ex))) { 426 continue; 427 } 428 429 if (pai->ai_family == PF_UNSPEC) 430 pai->ai_family = ex->e_af; 431 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 432 pai->ai_socktype = ex->e_socktype; 433 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 434 pai->ai_protocol = ex->e_protocol; 435 436 error = explore_fqdn(pai, hostname, servname, 437 &cur->ai_next); 438 439 while (cur && cur->ai_next) 440 cur = cur->ai_next; 441 } 442 } 443 444 /* XXX */ 445 if (sentinel.ai_next) 446 error = 0; 447 448 if (error) 449 goto free; 450 if (error == 0) { 451 if (sentinel.ai_next) { 452 good: 453 *res = sentinel.ai_next; 454 return SUCCESS; 455 } else 456 error = EAI_FAIL; 457 } 458 free: 459 bad: 460 if (sentinel.ai_next) 461 freeaddrinfo(sentinel.ai_next); 462 *res = NULL; 463 return error; 464 } 465 466 /* 467 * FQDN hostname, DNS lookup 468 */ 469 static int 470 explore_fqdn(pai, hostname, servname, res) 471 const struct addrinfo *pai; 472 const char *hostname; 473 const char *servname; 474 struct addrinfo **res; 475 { 476 #if 0 477 int s; 478 #endif 479 struct hostent *hp; 480 int h_error; 481 int af; 482 char **aplist = NULL, *apbuf = NULL; 483 char *ap; 484 struct addrinfo sentinel, *cur; 485 int i; 486 #ifndef USE_GETIPNODEBY 487 int naddrs; 488 #endif 489 const struct afd *afd; 490 int error; 491 492 *res = NULL; 493 sentinel.ai_next = NULL; 494 cur = &sentinel; 495 496 #if 0 497 /* 498 * filter out AFs that are not supported by the kernel 499 * XXX errno? 500 */ 501 s = socket(pai->ai_family, SOCK_DGRAM, 0); 502 if (s < 0) { 503 if (errno != EMFILE) 504 return 0; 505 } else 506 close(s); 507 #endif 508 509 /* 510 * if the servname does not match socktype/protocol, ignore it. 511 */ 512 if (get_portmatch(pai, servname) != 0) 513 return 0; 514 515 afd = find_afd(pai->ai_family); 516 517 /* 518 * post-RFC2553: should look at (pai->ai_flags & AI_ADDRCONFIG) 519 * rather than hardcoding it. we may need to add AI_ADDRCONFIG 520 * handling code by ourselves in case we don't have getipnodebyname(). 521 */ 522 #ifdef USE_GETIPNODEBY 523 hp = getipnodebyname(hostname, pai->ai_family, AI_ADDRCONFIG, &h_error); 524 #else 525 hp = gethostbyname2(hostname, pai->ai_family); 526 h_error = h_errno; 527 #endif 528 529 if (hp == NULL) { 530 switch (h_error) { 531 case HOST_NOT_FOUND: 532 case NO_DATA: 533 error = EAI_NODATA; 534 break; 535 case TRY_AGAIN: 536 error = EAI_AGAIN; 537 break; 538 case NO_RECOVERY: 539 case NETDB_INTERNAL: 540 default: 541 error = EAI_FAIL; 542 break; 543 } 544 } else if ((hp->h_name == NULL) || (hp->h_name[0] == 0) 545 || (hp->h_addr_list[0] == NULL)) { 546 #ifdef USE_GETIPNODEBY 547 freehostent(hp); 548 #endif 549 hp = NULL; 550 error = EAI_FAIL; 551 } 552 553 if (hp == NULL) 554 goto free; 555 556 #ifdef USE_GETIPNODEBY 557 aplist = hp->h_addr_list; 558 #else 559 /* 560 * hp will be overwritten if we use gethostbyname2(). 561 * always deep copy for simplification. 562 */ 563 for (naddrs = 0; hp->h_addr_list[naddrs] != NULL; naddrs++) 564 ; 565 naddrs++; 566 aplist = (char **)malloc(sizeof(aplist[0]) * naddrs); 567 apbuf = (char *)malloc((size_t)hp->h_length * naddrs); 568 if (aplist == NULL || apbuf == NULL) { 569 error = EAI_MEMORY; 570 goto free; 571 } 572 memset(aplist, 0, sizeof(aplist[0]) * naddrs); 573 for (i = 0; i < naddrs; i++) { 574 if (hp->h_addr_list[i] == NULL) { 575 aplist[i] = NULL; 576 continue; 577 } 578 memcpy(&apbuf[i * hp->h_length], hp->h_addr_list[i], 579 (size_t)hp->h_length); 580 aplist[i] = &apbuf[i * hp->h_length]; 581 } 582 #endif 583 584 for (i = 0; aplist[i] != NULL; i++) { 585 af = hp->h_addrtype; 586 ap = aplist[i]; 587 if (af == AF_INET6 588 && IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ap)) { 589 af = AF_INET; 590 ap = ap + sizeof(struct in6_addr) 591 - sizeof(struct in_addr); 592 } 593 594 if (af != pai->ai_family) 595 continue; 596 597 if ((pai->ai_flags & AI_CANONNAME) == 0) { 598 GET_AI(cur->ai_next, afd, ap); 599 GET_PORT(cur->ai_next, servname); 600 } else { 601 /* 602 * if AI_CANONNAME and if reverse lookup 603 * fail, return ai anyway to pacify 604 * calling application. 605 * 606 * XXX getaddrinfo() is a name->address 607 * translation function, and it looks 608 * strange that we do addr->name 609 * translation here. 610 */ 611 get_name(ap, afd, &cur->ai_next, 612 ap, pai, servname); 613 } 614 615 while (cur && cur->ai_next) 616 cur = cur->ai_next; 617 } 618 619 *res = sentinel.ai_next; 620 return 0; 621 622 free: 623 #ifdef USE_GETIPNODEBY 624 if (hp) 625 freehostent(hp); 626 #endif 627 if (aplist) 628 free(aplist); 629 if (apbuf) 630 free(apbuf); 631 if (sentinel.ai_next) 632 freeaddrinfo(sentinel.ai_next); 633 return error; 634 } 635 636 /* 637 * hostname == NULL. 638 * passive socket -> anyaddr (0.0.0.0 or ::) 639 * non-passive socket -> localhost (127.0.0.1 or ::1) 640 */ 641 static int 642 explore_null(pai, servname, res) 643 const struct addrinfo *pai; 644 const char *servname; 645 struct addrinfo **res; 646 { 647 int s; 648 const struct afd *afd; 649 struct addrinfo *cur; 650 struct addrinfo sentinel; 651 int error; 652 653 *res = NULL; 654 sentinel.ai_next = NULL; 655 cur = &sentinel; 656 657 /* 658 * filter out AFs that are not supported by the kernel 659 * XXX errno? 660 */ 661 s = socket(pai->ai_family, SOCK_DGRAM, 0); 662 if (s < 0) { 663 if (errno != EMFILE) 664 return 0; 665 } else 666 close(s); 667 668 /* 669 * if the servname does not match socktype/protocol, ignore it. 670 */ 671 if (get_portmatch(pai, servname) != 0) 672 return 0; 673 674 afd = find_afd(pai->ai_family); 675 676 if (pai->ai_flags & AI_PASSIVE) { 677 GET_AI(cur->ai_next, afd, afd->a_addrany); 678 /* xxx meaningless? 679 * GET_CANONNAME(cur->ai_next, "anyaddr"); 680 */ 681 GET_PORT(cur->ai_next, servname); 682 } else { 683 GET_AI(cur->ai_next, afd, afd->a_loopback); 684 /* xxx meaningless? 685 * GET_CANONNAME(cur->ai_next, "localhost"); 686 */ 687 GET_PORT(cur->ai_next, servname); 688 } 689 cur = cur->ai_next; 690 691 *res = sentinel.ai_next; 692 return 0; 693 694 free: 695 if (sentinel.ai_next) 696 freeaddrinfo(sentinel.ai_next); 697 return error; 698 } 699 700 /* 701 * numeric hostname 702 */ 703 static int 704 explore_numeric(pai, hostname, servname, res) 705 const struct addrinfo *pai; 706 const char *hostname; 707 const char *servname; 708 struct addrinfo **res; 709 { 710 const struct afd *afd; 711 struct addrinfo *cur; 712 struct addrinfo sentinel; 713 int error; 714 char pton[PTON_MAX]; 715 int flags; 716 717 *res = NULL; 718 sentinel.ai_next = NULL; 719 cur = &sentinel; 720 721 /* 722 * if the servname does not match socktype/protocol, ignore it. 723 */ 724 if (get_portmatch(pai, servname) != 0) 725 return 0; 726 727 afd = find_afd(pai->ai_family); 728 flags = pai->ai_flags; 729 730 if (inet_pton(afd->a_af, hostname, pton) == 1) { 731 u_int32_t v4a; 732 #ifdef INET6 733 u_char pfx; 734 #endif 735 736 switch (afd->a_af) { 737 case AF_INET: 738 v4a = (u_int32_t)ntohl(((struct in_addr *)pton)->s_addr); 739 if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a)) 740 flags &= ~AI_CANONNAME; 741 v4a >>= IN_CLASSA_NSHIFT; 742 if (v4a == 0 || v4a == IN_LOOPBACKNET) 743 flags &= ~AI_CANONNAME; 744 break; 745 #ifdef INET6 746 case AF_INET6: 747 pfx = ((struct in6_addr *)pton)->s6_addr[0]; 748 if (pfx == 0 || pfx == 0xfe || pfx == 0xff) 749 flags &= ~AI_CANONNAME; 750 break; 751 #endif 752 } 753 754 if (pai->ai_family == afd->a_af || 755 pai->ai_family == PF_UNSPEC /*?*/) { 756 if ((flags & AI_CANONNAME) == 0) { 757 GET_AI(cur->ai_next, afd, pton); 758 GET_PORT(cur->ai_next, servname); 759 } else { 760 /* 761 * if AI_CANONNAME and if reverse lookup 762 * fail, return ai anyway to pacify 763 * calling application. 764 * 765 * XXX getaddrinfo() is a name->address 766 * translation function, and it looks 767 * strange that we do addr->name 768 * translation here. 769 */ 770 get_name(pton, afd, &cur->ai_next, 771 pton, pai, servname); 772 } 773 while (cur && cur->ai_next) 774 cur = cur->ai_next; 775 } else 776 ERR(EAI_FAMILY); /*xxx*/ 777 } 778 779 *res = sentinel.ai_next; 780 return 0; 781 782 free: 783 bad: 784 if (sentinel.ai_next) 785 freeaddrinfo(sentinel.ai_next); 786 return error; 787 } 788 789 /* 790 * numeric hostname with scope 791 */ 792 static int 793 explore_numeric_scope(pai, hostname, servname, res) 794 const struct addrinfo *pai; 795 const char *hostname; 796 const char *servname; 797 struct addrinfo **res; 798 { 799 #ifndef SCOPE_DELIMITER 800 return explore_numeric(pai, hostname, servname, res); 801 #else 802 const struct afd *afd; 803 struct addrinfo *cur; 804 int error; 805 char *cp, *hostname2 = NULL; 806 int scope; 807 struct sockaddr_in6 *sin6; 808 809 /* 810 * if the servname does not match socktype/protocol, ignore it. 811 */ 812 if (get_portmatch(pai, servname) != 0) 813 return 0; 814 815 afd = find_afd(pai->ai_family); 816 if (!afd->a_scoped) 817 return explore_numeric(pai, hostname, servname, res); 818 819 cp = strchr(hostname, SCOPE_DELIMITER); 820 if (cp == NULL) 821 return explore_numeric(pai, hostname, servname, res); 822 823 /* 824 * Handle special case of <scoped_address><delimiter><scope id> 825 */ 826 hostname2 = strdup(hostname); 827 if (hostname2 == NULL) 828 return EAI_MEMORY; 829 /* terminate at the delimiter */ 830 hostname2[cp - hostname] = '\0'; 831 832 cp++; 833 switch (pai->ai_family) { 834 #ifdef INET6 835 case AF_INET6: 836 scope = if_nametoindex(cp); 837 if (scope == 0) { 838 free(hostname2); 839 return (EAI_NONAME); 840 } 841 break; 842 #endif 843 } 844 845 error = explore_numeric(pai, hostname2, servname, res); 846 if (error == 0) { 847 for (cur = *res; cur; cur = cur->ai_next) { 848 if (cur->ai_family != AF_INET6) 849 continue; 850 sin6 = (struct sockaddr_in6 *)cur->ai_addr; 851 if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr) || 852 IN6_IS_ADDR_MC_LINKLOCAL(&sin6->sin6_addr)) 853 sin6->sin6_scope_id = scope; 854 } 855 } 856 857 free(hostname2); 858 859 return error; 860 #endif 861 } 862 863 static int 864 get_name(addr, afd, res, numaddr, pai, servname) 865 const char *addr; 866 const struct afd *afd; 867 struct addrinfo **res; 868 char *numaddr; 869 const struct addrinfo *pai; 870 const char *servname; 871 { 872 struct hostent *hp = NULL; 873 struct addrinfo *cur = NULL; 874 int error = 0; 875 char *ap = NULL, *cn = NULL; 876 #ifdef USE_GETIPNODEBY 877 int h_error; 878 879 hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error); 880 #else 881 hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af); 882 #endif 883 if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) { 884 #ifdef USE_GETIPNODEBY 885 GET_AI(cur, afd, hp->h_addr_list[0]); 886 GET_PORT(cur, servname); 887 GET_CANONNAME(cur, hp->h_name); 888 #else 889 /* hp will be damaged if we use gethostbyaddr() */ 890 if ((ap = (char *)malloc((size_t)hp->h_length)) == NULL) { 891 error = EAI_MEMORY; 892 goto free; 893 } 894 memcpy(ap, hp->h_addr_list[0], (size_t)hp->h_length); 895 if ((cn = strdup(hp->h_name)) == NULL) { 896 error = EAI_MEMORY; 897 goto free; 898 } 899 900 GET_AI(cur, afd, ap); 901 GET_PORT(cur, servname); 902 GET_CANONNAME(cur, cn); 903 free(ap); ap = NULL; 904 free(cn); cn = NULL; 905 #endif 906 } else { 907 GET_AI(cur, afd, numaddr); 908 GET_PORT(cur, servname); 909 } 910 911 #ifdef USE_GETIPNODEBY 912 if (hp) 913 freehostent(hp); 914 #endif 915 *res = cur; 916 return SUCCESS; 917 free: 918 if (cur) 919 freeaddrinfo(cur); 920 if (ap) 921 free(ap); 922 if (cn) 923 free(cn); 924 #ifdef USE_GETIPNODEBY 925 if (hp) 926 freehostent(hp); 927 #endif 928 *res = NULL; 929 return error; 930 } 931 932 static int 933 get_canonname(pai, ai, str) 934 const struct addrinfo *pai; 935 struct addrinfo *ai; 936 const char *str; 937 { 938 if ((pai->ai_flags & AI_CANONNAME) != 0) { 939 ai->ai_canonname = (char *)malloc(strlen(str) + 1); 940 if (ai->ai_canonname == NULL) 941 return EAI_MEMORY; 942 strcpy(ai->ai_canonname, str); 943 } 944 return 0; 945 } 946 947 static struct addrinfo * 948 get_ai(pai, afd, addr) 949 const struct addrinfo *pai; 950 const struct afd *afd; 951 const char *addr; 952 { 953 char *p; 954 struct addrinfo *ai; 955 956 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 957 + (afd->a_socklen)); 958 if (ai == NULL) 959 return NULL; 960 961 memcpy(ai, pai, sizeof(struct addrinfo)); 962 ai->ai_addr = (struct sockaddr *)(ai + 1); 963 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 964 ai->ai_addr->sa_len = afd->a_socklen; 965 ai->ai_addrlen = afd->a_socklen; 966 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 967 p = (char *)(ai->ai_addr); 968 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 969 return ai; 970 } 971 972 static int 973 get_portmatch(ai, servname) 974 const struct addrinfo *ai; 975 const char *servname; 976 { 977 978 /* get_port does not touch first argument. when matchonly == 1. */ 979 return get_port((struct addrinfo *)ai, servname, 1); 980 } 981 982 static int 983 get_port(ai, servname, matchonly) 984 struct addrinfo *ai; 985 const char *servname; 986 int matchonly; 987 { 988 const char *proto; 989 struct servent *sp; 990 int port; 991 int allownumeric; 992 993 if (servname == NULL) 994 return 0; 995 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) 996 return 0; 997 998 switch (ai->ai_socktype) { 999 case SOCK_RAW: 1000 return EAI_SERVICE; 1001 case SOCK_DGRAM: 1002 case SOCK_STREAM: 1003 allownumeric = 1; 1004 break; 1005 case ANY: 1006 allownumeric = 0; 1007 break; 1008 default: 1009 return EAI_SOCKTYPE; 1010 } 1011 1012 if (str_isnumber(servname)) { 1013 if (!allownumeric) 1014 return EAI_SERVICE; 1015 port = htons(atoi(servname)); 1016 if (port < 0 || port > 65535) 1017 return EAI_SERVICE; 1018 } else { 1019 switch (ai->ai_socktype) { 1020 case SOCK_DGRAM: 1021 proto = "udp"; 1022 break; 1023 case SOCK_STREAM: 1024 proto = "tcp"; 1025 break; 1026 default: 1027 proto = NULL; 1028 break; 1029 } 1030 1031 if ((sp = getservbyname(servname, proto)) == NULL) 1032 return EAI_SERVICE; 1033 port = sp->s_port; 1034 } 1035 1036 if (!matchonly) { 1037 switch (ai->ai_family) { 1038 case AF_INET: 1039 ((struct sockaddr_in *)ai->ai_addr)->sin_port = port; 1040 break; 1041 #ifdef INET6 1042 case AF_INET6: 1043 ((struct sockaddr_in6 *)ai->ai_addr)->sin6_port = port; 1044 break; 1045 #endif 1046 } 1047 } 1048 1049 return 0; 1050 } 1051 1052 static const struct afd * 1053 find_afd(af) 1054 int af; 1055 { 1056 const struct afd *afd; 1057 1058 if (af == PF_UNSPEC) 1059 return NULL; 1060 for (afd = afdl; afd->a_af; afd++) { 1061 if (afd->a_af == af) 1062 return afd; 1063 } 1064 return NULL; 1065 } 1066
Indexes created Tue Sep 30 11:09:46 GMT 2025