getaddrinfo.c revision 1.18
1 /* $NetBSD: getaddrinfo.c,v 1.18 2000/01/17 08:34:04 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 * 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 *, const char *, 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 (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 (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 (0) 212 213 #define ERR(err) \ 214 do { \ 215 /* external reference: error, and label bad */ \ 216 error = (err); \ 217 goto bad; \ 218 } while (0) 219 220 #define MATCH_FAMILY(x, y, w) \ 221 ((x) == (y) || ((w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) 222 #define MATCH(x, y, w) \ 223 ((x) == (y) || ((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 char *q = (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 ai0 = *pai; 350 351 if (pai->ai_family == PF_UNSPEC) 352 pai->ai_family = PF_INET6; 353 error = get_portmatch(pai, servname); 354 if (error) 355 ERR(error); 356 357 *pai = ai0; 358 } 359 360 ai0 = *pai; 361 362 /* NULL hostname, or numeric hostname */ 363 for (ex = explore; ex->e_af >= 0; ex++) { 364 *pai = ai0; 365 366 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 367 continue; 368 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 369 continue; 370 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 371 continue; 372 373 if (pai->ai_family == PF_UNSPEC) 374 pai->ai_family = ex->e_af; 375 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 376 pai->ai_socktype = ex->e_socktype; 377 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 378 pai->ai_protocol = ex->e_protocol; 379 380 if (hostname == NULL) 381 error = explore_null(pai, hostname, servname, &cur->ai_next); 382 else 383 error = explore_numeric_scope(pai, hostname, servname, &cur->ai_next); 384 385 if (error) 386 goto free; 387 388 while (cur && cur->ai_next) 389 cur = cur->ai_next; 390 } 391 392 /* 393 * XXX 394 * If numreic representation of AF1 can be interpreted as FQDN 395 * representation of AF2, we need to think again about the code below. 396 */ 397 if (sentinel.ai_next) 398 goto good; 399 400 if (pai->ai_flags & AI_NUMERICHOST) 401 ERR(EAI_NONAME); 402 if (hostname == NULL) 403 ERR(EAI_NONAME); 404 405 /* 406 * hostname as alphabetical name. 407 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 408 * outer loop by AFs. 409 */ 410 for (afd = afdl; afd->a_af; afd++) { 411 *pai = ai0; 412 413 if (!MATCH_FAMILY(pai->ai_family, afd->a_af, 1)) 414 continue; 415 416 for (ex = explore; ex->e_af >= 0; ex++) { 417 *pai = ai0; 418 419 if (pai->ai_family == PF_UNSPEC) 420 pai->ai_family = afd->a_af; 421 422 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 423 continue; 424 if (!MATCH(pai->ai_socktype, ex->e_socktype, 425 WILD_SOCKTYPE(ex))) { 426 continue; 427 } 428 if (!MATCH(pai->ai_protocol, ex->e_protocol, 429 WILD_PROTOCOL(ex))) { 430 continue; 431 } 432 433 if (pai->ai_family == PF_UNSPEC) 434 pai->ai_family = ex->e_af; 435 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 436 pai->ai_socktype = ex->e_socktype; 437 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 438 pai->ai_protocol = ex->e_protocol; 439 440 error = explore_fqdn(pai, hostname, servname, 441 &cur->ai_next); 442 443 while (cur && cur->ai_next) 444 cur = cur->ai_next; 445 } 446 } 447 448 /* XXX */ 449 if (sentinel.ai_next) 450 error = 0; 451 452 if (error) 453 goto free; 454 if (error == 0) { 455 if (sentinel.ai_next) { 456 good: 457 *res = sentinel.ai_next; 458 return SUCCESS; 459 } else 460 error = EAI_FAIL; 461 } 462 free: 463 bad: 464 if (sentinel.ai_next) 465 freeaddrinfo(sentinel.ai_next); 466 *res = NULL; 467 return error; 468 } 469 470 /* 471 * FQDN hostname, DNS lookup 472 */ 473 static int 474 explore_fqdn(pai, hostname, servname, res) 475 const struct addrinfo *pai; 476 const char *hostname; 477 const char *servname; 478 struct addrinfo **res; 479 { 480 int s; 481 struct hostent *hp; 482 int h_error; 483 int af; 484 char **aplist = NULL, *apbuf = NULL; 485 char *ap; 486 struct addrinfo sentinel, *cur; 487 int i; 488 #ifndef USE_GETIPNODEBY 489 int naddrs; 490 #endif 491 const struct afd *afd; 492 int error; 493 494 *res = NULL; 495 sentinel.ai_next = NULL; 496 cur = &sentinel; 497 498 /* 499 * filter out AFs that are not supported by the kernel 500 * XXX errno? 501 */ 502 s = socket(pai->ai_family, SOCK_DGRAM, 0); 503 if (s < 0) { 504 if (errno != EMFILE) 505 return 0; 506 } else 507 close(s); 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(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 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, hostname, servname, res) 643 const struct addrinfo *pai; 644 const char *hostname; 645 const char *servname; 646 struct addrinfo **res; 647 { 648 int s; 649 const struct afd *afd; 650 struct addrinfo *cur; 651 struct addrinfo sentinel; 652 int error; 653 654 *res = NULL; 655 sentinel.ai_next = NULL; 656 cur = &sentinel; 657 658 /* 659 * filter out AFs that are not supported by the kernel 660 * XXX errno? 661 */ 662 s = socket(pai->ai_family, SOCK_DGRAM, 0); 663 if (s < 0) { 664 if (errno != EMFILE) 665 return 0; 666 } else 667 close(s); 668 669 /* 670 * if the servname does not match socktype/protocol, ignore it. 671 */ 672 if (get_portmatch(pai, servname) != 0) 673 return 0; 674 675 afd = find_afd(pai->ai_family); 676 677 if (pai->ai_flags & AI_PASSIVE) { 678 GET_AI(cur->ai_next, afd, afd->a_addrany); 679 /* xxx meaningless? 680 * GET_CANONNAME(cur->ai_next, "anyaddr"); 681 */ 682 GET_PORT(cur->ai_next, servname); 683 } else { 684 GET_AI(cur->ai_next, afd, afd->a_loopback); 685 /* xxx meaningless? 686 * GET_CANONNAME(cur->ai_next, "localhost"); 687 */ 688 GET_PORT(cur->ai_next, servname); 689 } 690 cur = cur->ai_next; 691 692 *res = sentinel.ai_next; 693 return 0; 694 695 free: 696 if (sentinel.ai_next) 697 freeaddrinfo(sentinel.ai_next); 698 return error; 699 } 700 701 /* 702 * numeric hostname 703 */ 704 static int 705 explore_numeric(pai, hostname, servname, res) 706 const struct addrinfo *pai; 707 const char *hostname; 708 const char *servname; 709 struct addrinfo **res; 710 { 711 const struct afd *afd; 712 struct addrinfo *cur; 713 struct addrinfo sentinel; 714 int error; 715 char pton[PTON_MAX]; 716 int flags; 717 718 *res = NULL; 719 sentinel.ai_next = NULL; 720 cur = &sentinel; 721 722 /* 723 * if the servname does not match socktype/protocol, ignore it. 724 */ 725 if (get_portmatch(pai, servname) != 0) 726 return 0; 727 728 afd = find_afd(pai->ai_family); 729 flags = pai->ai_flags; 730 731 if (inet_pton(afd->a_af, hostname, pton) == 1) { 732 u_int32_t v4a; 733 #ifdef INET6 734 u_char pfx; 735 #endif 736 737 switch (afd->a_af) { 738 case AF_INET: 739 v4a = (u_int32_t)ntohl(((struct in_addr *)pton)->s_addr); 740 if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a)) 741 flags &= ~AI_CANONNAME; 742 v4a >>= IN_CLASSA_NSHIFT; 743 if (v4a == 0 || v4a == IN_LOOPBACKNET) 744 flags &= ~AI_CANONNAME; 745 break; 746 #ifdef INET6 747 case AF_INET6: 748 pfx = ((struct in6_addr *)pton)->s6_addr[0]; 749 if (pfx == 0 || pfx == 0xfe || pfx == 0xff) 750 flags &= ~AI_CANONNAME; 751 break; 752 #endif 753 } 754 755 if (pai->ai_family == afd->a_af || 756 pai->ai_family == PF_UNSPEC /*?*/) { 757 if ((flags & AI_CANONNAME) == 0) { 758 GET_AI(cur->ai_next, afd, pton); 759 GET_PORT(cur->ai_next, servname); 760 } else { 761 /* 762 * if AI_CANONNAME and if reverse lookup 763 * fail, return ai anyway to pacify 764 * calling application. 765 * 766 * XXX getaddrinfo() is a name->address 767 * translation function, and it looks 768 * strange that we do addr->name 769 * translation here. 770 */ 771 get_name(pton, afd, &cur->ai_next, 772 pton, pai, servname); 773 } 774 while (cur && cur->ai_next) 775 cur = cur->ai_next; 776 } else 777 ERR(EAI_FAMILY); /*xxx*/ 778 } 779 780 *res = sentinel.ai_next; 781 return 0; 782 783 free: 784 bad: 785 if (sentinel.ai_next) 786 freeaddrinfo(sentinel.ai_next); 787 return error; 788 } 789 790 /* 791 * numeric hostname with scope 792 */ 793 static int 794 explore_numeric_scope(pai, hostname, servname, res) 795 const struct addrinfo *pai; 796 const char *hostname; 797 const char *servname; 798 struct addrinfo **res; 799 { 800 #ifndef SCOPE_DELIMITER 801 return explore_numeric(pai, hostname, servname, res); 802 #else 803 const struct afd *afd; 804 struct addrinfo *cur; 805 int error; 806 char *cp, *hostname2 = NULL; 807 int scope; 808 struct sockaddr_in6 *sin6; 809 810 /* 811 * if the servname does not match socktype/protocol, ignore it. 812 */ 813 if (get_portmatch(pai, servname) != 0) 814 return 0; 815 816 afd = find_afd(pai->ai_family); 817 if (!afd->a_scoped) 818 return explore_numeric(pai, hostname, servname, res); 819 820 cp = strchr(hostname, SCOPE_DELIMITER); 821 if (cp == NULL) 822 return explore_numeric(pai, hostname, servname, res); 823 824 /* 825 * Handle special case of <scoped_address><delimiter><scope id> 826 */ 827 hostname2 = strdup(hostname); 828 if (hostname2 == NULL) 829 return EAI_MEMORY; 830 /* terminate at the delimiter */ 831 hostname2[cp - hostname] = '\0'; 832 833 cp++; 834 switch (pai->ai_family) { 835 #ifdef INET6 836 case AF_INET6: 837 scope = if_nametoindex(cp); 838 if (scope == 0) { 839 free(hostname2); 840 return (EAI_NONAME); 841 } 842 break; 843 #endif 844 } 845 846 error = explore_numeric(pai, hostname2, servname, res); 847 if (error == 0) { 848 for (cur = *res; cur; cur = cur->ai_next) { 849 if (cur->ai_family != AF_INET6) 850 continue; 851 sin6 = (struct sockaddr_in6 *)cur->ai_addr; 852 if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr) || 853 IN6_IS_ADDR_MC_LINKLOCAL(&sin6->sin6_addr)) 854 sin6->sin6_scope_id = scope; 855 } 856 } 857 858 free(hostname2); 859 860 return error; 861 #endif 862 } 863 864 static int 865 get_name(addr, afd, res, numaddr, pai, servname) 866 const char *addr; 867 const struct afd *afd; 868 struct addrinfo **res; 869 char *numaddr; 870 const struct addrinfo *pai; 871 const char *servname; 872 { 873 struct hostent *hp = NULL; 874 struct addrinfo *cur = NULL; 875 int error = 0; 876 char *ap = NULL, *cn = NULL; 877 #ifdef USE_GETIPNODEBY 878 int h_error; 879 880 hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error); 881 #else 882 hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af); 883 #endif 884 if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) { 885 #ifdef USE_GETIPNODEBY 886 GET_AI(cur, afd, hp->h_addr_list[0]); 887 GET_PORT(cur, servname); 888 GET_CANONNAME(cur, hp->h_name); 889 #else 890 /* hp will be damaged if we use gethostbyaddr() */ 891 if ((ap = (char *)malloc(hp->h_length)) == NULL) { 892 error = EAI_MEMORY; 893 goto free; 894 } 895 memcpy(ap, hp->h_addr_list[0], hp->h_length); 896 if ((cn = strdup(hp->h_name)) == NULL) { 897 error = EAI_MEMORY; 898 goto free; 899 } 900 901 GET_AI(cur, afd, ap); 902 GET_PORT(cur, servname); 903 GET_CANONNAME(cur, cn); 904 free(ap); ap = NULL; 905 free(cn); cn = NULL; 906 #endif 907 } else { 908 GET_AI(cur, afd, numaddr); 909 GET_PORT(cur, servname); 910 } 911 912 #ifdef USE_GETIPNODEBY 913 if (hp) 914 freehostent(hp); 915 #endif 916 *res = cur; 917 return SUCCESS; 918 free: 919 if (cur) 920 freeaddrinfo(cur); 921 if (ap) 922 free(ap); 923 if (cn) 924 free(cn); 925 #ifdef USE_GETIPNODEBY 926 if (hp) 927 freehostent(hp); 928 #endif 929 *res = NULL; 930 return error; 931 } 932 933 static int 934 get_canonname(pai, ai, str) 935 const struct addrinfo *pai; 936 struct addrinfo *ai; 937 const char *str; 938 { 939 if ((pai->ai_flags & AI_CANONNAME) != 0) { 940 ai->ai_canonname = (char *)malloc(strlen(str) + 1); 941 if (ai->ai_canonname == NULL) 942 return EAI_MEMORY; 943 strcpy(ai->ai_canonname, str); 944 } 945 return 0; 946 } 947 948 static struct addrinfo * 949 get_ai(pai, afd, addr) 950 const struct addrinfo *pai; 951 const struct afd *afd; 952 const char *addr; 953 { 954 char *p; 955 struct addrinfo *ai; 956 957 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 958 + (afd->a_socklen)); 959 if (ai == NULL) 960 return NULL; 961 962 memcpy(ai, pai, sizeof(struct addrinfo)); 963 ai->ai_addr = (struct sockaddr *)(ai + 1); 964 memset(ai->ai_addr, 0, afd->a_socklen); 965 ai->ai_addr->sa_len = afd->a_socklen; 966 ai->ai_addrlen = afd->a_socklen; 967 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 968 p = (char *)(ai->ai_addr); 969 memcpy(p + afd->a_off, addr, afd->a_addrlen); 970 return ai; 971 } 972 973 static int 974 get_portmatch(ai, servname) 975 const struct addrinfo *ai; 976 const char *servname; 977 { 978 979 /* get_port does not touch first argument. when matchonly == 1. */ 980 return get_port((struct addrinfo *)ai, servname, 1); 981 } 982 983 static int 984 get_port(ai, servname, matchonly) 985 struct addrinfo *ai; 986 const char *servname; 987 int matchonly; 988 { 989 const char *proto; 990 struct servent *sp; 991 int port; 992 int allownumeric; 993 994 if (servname == NULL) 995 return 0; 996 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) 997 return 0; 998 999 switch (ai->ai_socktype) { 1000 case SOCK_RAW: 1001 return EAI_SERVICE; 1002 case SOCK_DGRAM: 1003 case SOCK_STREAM: 1004 allownumeric = 1; 1005 break; 1006 case ANY: 1007 allownumeric = 0; 1008 break; 1009 default: 1010 return EAI_SOCKTYPE; 1011 } 1012 1013 if (str_isnumber(servname)) { 1014 if (!allownumeric) 1015 return EAI_SERVICE; 1016 port = htons(atoi(servname)); 1017 if (port < 0 || port > 65535) 1018 return EAI_SERVICE; 1019 } else { 1020 switch (ai->ai_socktype) { 1021 case SOCK_DGRAM: 1022 proto = "udp"; 1023 break; 1024 case SOCK_STREAM: 1025 proto = "tcp"; 1026 break; 1027 default: 1028 proto = NULL; 1029 break; 1030 } 1031 1032 if ((sp = getservbyname(servname, proto)) == NULL) 1033 return EAI_SERVICE; 1034 port = sp->s_port; 1035 } 1036 1037 if (!matchonly) { 1038 switch (ai->ai_family) { 1039 case AF_INET: 1040 ((struct sockaddr_in *)ai->ai_addr)->sin_port = port; 1041 break; 1042 #ifdef INET6 1043 case AF_INET6: 1044 ((struct sockaddr_in6 *)ai->ai_addr)->sin6_port = port; 1045 break; 1046 #endif 1047 } 1048 } 1049 1050 return 0; 1051 } 1052 1053 static const struct afd * 1054 find_afd(af) 1055 int af; 1056 { 1057 const struct afd *afd; 1058 1059 if (af == PF_UNSPEC) 1060 return NULL; 1061 for (afd = afdl; afd->a_af; afd++) { 1062 if (afd->a_af == af) 1063 return afd; 1064 } 1065 return NULL; 1066 } 1067
Indexes created Tue Sep 30 07:10:03 GMT 2025