getaddrinfo.c revision 1.22
1 /* $NetBSD: getaddrinfo.c,v 1.22 2000/01/23 04:03:21 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 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 */ 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 /* call to get_portmatch() can conterminate *pai */ 350 ai0 = *pai; 351 352 if (pai->ai_family == PF_UNSPEC) 353 pai->ai_family = PF_INET6; 354 error = get_portmatch(pai, servname); 355 if (error) 356 ERR(error); 357 358 *pai = ai0; 359 } 360 361 ai0 = *pai; 362 363 /* NULL hostname, or numeric hostname */ 364 for (ex = explore; ex->e_af >= 0; ex++) { 365 *pai = ai0; 366 367 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 368 continue; 369 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) 370 continue; 371 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) 372 continue; 373 374 if (pai->ai_family == PF_UNSPEC) 375 pai->ai_family = ex->e_af; 376 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 377 pai->ai_socktype = ex->e_socktype; 378 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 379 pai->ai_protocol = ex->e_protocol; 380 381 if (hostname == NULL) 382 error = explore_null(pai, servname, &cur->ai_next); 383 else 384 error = explore_numeric_scope(pai, hostname, servname, &cur->ai_next); 385 386 if (error) 387 goto free; 388 389 while (cur && cur->ai_next) 390 cur = cur->ai_next; 391 } 392 393 /* 394 * XXX 395 * If numreic representation of AF1 can be interpreted as FQDN 396 * representation of AF2, we need to think again about the code below. 397 */ 398 if (sentinel.ai_next) 399 goto good; 400 401 if (pai->ai_flags & AI_NUMERICHOST) 402 ERR(EAI_NONAME); 403 if (hostname == NULL) 404 ERR(EAI_NONAME); 405 406 /* 407 * hostname as alphabetical name. 408 * we would like to prefer AF_INET6 than AF_INET, so we'll make a 409 * outer loop by AFs. 410 */ 411 for (afd = afdl; afd->a_af; afd++) { 412 *pai = ai0; 413 414 if (!MATCH_FAMILY(pai->ai_family, afd->a_af, 1)) 415 continue; 416 417 for (ex = explore; ex->e_af >= 0; ex++) { 418 *pai = ai0; 419 420 if (pai->ai_family == PF_UNSPEC) 421 pai->ai_family = afd->a_af; 422 423 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) 424 continue; 425 if (!MATCH(pai->ai_socktype, ex->e_socktype, 426 WILD_SOCKTYPE(ex))) { 427 continue; 428 } 429 if (!MATCH(pai->ai_protocol, ex->e_protocol, 430 WILD_PROTOCOL(ex))) { 431 continue; 432 } 433 434 if (pai->ai_family == PF_UNSPEC) 435 pai->ai_family = ex->e_af; 436 if (pai->ai_socktype == ANY && ex->e_socktype != ANY) 437 pai->ai_socktype = ex->e_socktype; 438 if (pai->ai_protocol == ANY && ex->e_protocol != ANY) 439 pai->ai_protocol = ex->e_protocol; 440 441 error = explore_fqdn(pai, hostname, servname, 442 &cur->ai_next); 443 444 while (cur && cur->ai_next) 445 cur = cur->ai_next; 446 } 447 } 448 449 /* XXX */ 450 if (sentinel.ai_next) 451 error = 0; 452 453 if (error) 454 goto free; 455 if (error == 0) { 456 if (sentinel.ai_next) { 457 good: 458 *res = sentinel.ai_next; 459 return SUCCESS; 460 } else 461 error = EAI_FAIL; 462 } 463 free: 464 bad: 465 if (sentinel.ai_next) 466 freeaddrinfo(sentinel.ai_next); 467 *res = NULL; 468 return error; 469 } 470 471 /* 472 * FQDN hostname, DNS lookup 473 */ 474 static int 475 explore_fqdn(pai, hostname, servname, res) 476 const struct addrinfo *pai; 477 const char *hostname; 478 const char *servname; 479 struct addrinfo **res; 480 { 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 * Do not filter unsupported AFs here. We need to honor content of 500 * databases (/etc/hosts, DNS and others). Otherwise we cannot 501 * replace gethostbyname() by getaddrinfo(). 502 */ 503 504 /* 505 * if the servname does not match socktype/protocol, ignore it. 506 */ 507 if (get_portmatch(pai, servname) != 0) 508 return 0; 509 510 afd = find_afd(pai->ai_family); 511 512 /* 513 * post-RFC2553: should look at (pai->ai_flags & AI_ADDRCONFIG) 514 * rather than hardcoding it. we may need to add AI_ADDRCONFIG 515 * handling code by ourselves in case we don't have getipnodebyname(). 516 */ 517 #ifdef USE_GETIPNODEBY 518 hp = getipnodebyname(hostname, pai->ai_family, AI_ADDRCONFIG, &h_error); 519 #else 520 hp = gethostbyname2(hostname, pai->ai_family); 521 h_error = h_errno; 522 #endif 523 524 if (hp == NULL) { 525 switch (h_error) { 526 case HOST_NOT_FOUND: 527 case NO_DATA: 528 error = EAI_NODATA; 529 break; 530 case TRY_AGAIN: 531 error = EAI_AGAIN; 532 break; 533 case NO_RECOVERY: 534 case NETDB_INTERNAL: 535 default: 536 error = EAI_FAIL; 537 break; 538 } 539 } else if ((hp->h_name == NULL) || (hp->h_name[0] == 0) 540 || (hp->h_addr_list[0] == NULL)) { 541 #ifdef USE_GETIPNODEBY 542 freehostent(hp); 543 #endif 544 hp = NULL; 545 error = EAI_FAIL; 546 } 547 548 if (hp == NULL) 549 goto free; 550 551 #ifdef USE_GETIPNODEBY 552 aplist = hp->h_addr_list; 553 #else 554 /* 555 * hp will be overwritten if we use gethostbyname2(). 556 * always deep copy for simplification. 557 */ 558 for (naddrs = 0; hp->h_addr_list[naddrs] != NULL; naddrs++) 559 ; 560 naddrs++; 561 aplist = (char **)malloc(sizeof(aplist[0]) * naddrs); 562 apbuf = (char *)malloc((size_t)hp->h_length * naddrs); 563 if (aplist == NULL || apbuf == NULL) { 564 error = EAI_MEMORY; 565 goto free; 566 } 567 memset(aplist, 0, sizeof(aplist[0]) * naddrs); 568 for (i = 0; i < naddrs; i++) { 569 if (hp->h_addr_list[i] == NULL) { 570 aplist[i] = NULL; 571 continue; 572 } 573 memcpy(&apbuf[i * hp->h_length], hp->h_addr_list[i], 574 (size_t)hp->h_length); 575 aplist[i] = &apbuf[i * hp->h_length]; 576 } 577 #endif 578 579 for (i = 0; aplist[i] != NULL; i++) { 580 af = hp->h_addrtype; 581 ap = aplist[i]; 582 if (af == AF_INET6 583 && IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ap)) { 584 af = AF_INET; 585 ap = ap + sizeof(struct in6_addr) 586 - sizeof(struct in_addr); 587 } 588 589 if (af != pai->ai_family) 590 continue; 591 592 if ((pai->ai_flags & AI_CANONNAME) == 0) { 593 GET_AI(cur->ai_next, afd, ap); 594 GET_PORT(cur->ai_next, servname); 595 } else { 596 /* 597 * if AI_CANONNAME and if reverse lookup 598 * fail, return ai anyway to pacify 599 * calling application. 600 * 601 * XXX getaddrinfo() is a name->address 602 * translation function, and it looks 603 * strange that we do addr->name 604 * translation here. 605 */ 606 get_name(ap, afd, &cur->ai_next, 607 ap, pai, servname); 608 } 609 610 while (cur && cur->ai_next) 611 cur = cur->ai_next; 612 } 613 614 *res = sentinel.ai_next; 615 return 0; 616 617 free: 618 #ifdef USE_GETIPNODEBY 619 if (hp) 620 freehostent(hp); 621 #endif 622 if (aplist) 623 free(aplist); 624 if (apbuf) 625 free(apbuf); 626 if (sentinel.ai_next) 627 freeaddrinfo(sentinel.ai_next); 628 return error; 629 } 630 631 /* 632 * hostname == NULL. 633 * passive socket -> anyaddr (0.0.0.0 or ::) 634 * non-passive socket -> localhost (127.0.0.1 or ::1) 635 */ 636 static int 637 explore_null(pai, servname, res) 638 const struct addrinfo *pai; 639 const char *servname; 640 struct addrinfo **res; 641 { 642 int s; 643 const struct afd *afd; 644 struct addrinfo *cur; 645 struct addrinfo sentinel; 646 int error; 647 648 *res = NULL; 649 sentinel.ai_next = NULL; 650 cur = &sentinel; 651 652 /* 653 * filter out AFs that are not supported by the kernel 654 * XXX errno? 655 */ 656 s = socket(pai->ai_family, SOCK_DGRAM, 0); 657 if (s < 0) { 658 if (errno != EMFILE) 659 return 0; 660 } else 661 close(s); 662 663 /* 664 * if the servname does not match socktype/protocol, ignore it. 665 */ 666 if (get_portmatch(pai, servname) != 0) 667 return 0; 668 669 afd = find_afd(pai->ai_family); 670 671 if (pai->ai_flags & AI_PASSIVE) { 672 GET_AI(cur->ai_next, afd, afd->a_addrany); 673 /* xxx meaningless? 674 * GET_CANONNAME(cur->ai_next, "anyaddr"); 675 */ 676 GET_PORT(cur->ai_next, servname); 677 } else { 678 GET_AI(cur->ai_next, afd, afd->a_loopback); 679 /* xxx meaningless? 680 * GET_CANONNAME(cur->ai_next, "localhost"); 681 */ 682 GET_PORT(cur->ai_next, servname); 683 } 684 cur = cur->ai_next; 685 686 *res = sentinel.ai_next; 687 return 0; 688 689 free: 690 if (sentinel.ai_next) 691 freeaddrinfo(sentinel.ai_next); 692 return error; 693 } 694 695 /* 696 * numeric hostname 697 */ 698 static int 699 explore_numeric(pai, hostname, servname, res) 700 const struct addrinfo *pai; 701 const char *hostname; 702 const char *servname; 703 struct addrinfo **res; 704 { 705 const struct afd *afd; 706 struct addrinfo *cur; 707 struct addrinfo sentinel; 708 int error; 709 char pton[PTON_MAX]; 710 int flags; 711 712 *res = NULL; 713 sentinel.ai_next = NULL; 714 cur = &sentinel; 715 716 /* 717 * if the servname does not match socktype/protocol, ignore it. 718 */ 719 if (get_portmatch(pai, servname) != 0) 720 return 0; 721 722 afd = find_afd(pai->ai_family); 723 flags = pai->ai_flags; 724 725 if (inet_pton(afd->a_af, hostname, pton) == 1) { 726 u_int32_t v4a; 727 #ifdef INET6 728 u_char pfx; 729 #endif 730 731 switch (afd->a_af) { 732 case AF_INET: 733 v4a = (u_int32_t)ntohl(((struct in_addr *)pton)->s_addr); 734 if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a)) 735 flags &= ~AI_CANONNAME; 736 v4a >>= IN_CLASSA_NSHIFT; 737 if (v4a == 0 || v4a == IN_LOOPBACKNET) 738 flags &= ~AI_CANONNAME; 739 break; 740 #ifdef INET6 741 case AF_INET6: 742 pfx = ((struct in6_addr *)pton)->s6_addr[0]; 743 if (pfx == 0 || pfx == 0xfe || pfx == 0xff) 744 flags &= ~AI_CANONNAME; 745 break; 746 #endif 747 } 748 749 if (pai->ai_family == afd->a_af || 750 pai->ai_family == PF_UNSPEC /*?*/) { 751 if ((flags & AI_CANONNAME) == 0) { 752 GET_AI(cur->ai_next, afd, pton); 753 GET_PORT(cur->ai_next, servname); 754 } else { 755 /* 756 * if AI_CANONNAME and if reverse lookup 757 * fail, return ai anyway to pacify 758 * calling application. 759 * 760 * XXX getaddrinfo() is a name->address 761 * translation function, and it looks 762 * strange that we do addr->name 763 * translation here. 764 */ 765 get_name(pton, afd, &cur->ai_next, 766 pton, pai, servname); 767 } 768 while (cur && cur->ai_next) 769 cur = cur->ai_next; 770 } else 771 ERR(EAI_FAMILY); /*xxx*/ 772 } 773 774 *res = sentinel.ai_next; 775 return 0; 776 777 free: 778 bad: 779 if (sentinel.ai_next) 780 freeaddrinfo(sentinel.ai_next); 781 return error; 782 } 783 784 /* 785 * numeric hostname with scope 786 */ 787 static int 788 explore_numeric_scope(pai, hostname, servname, res) 789 const struct addrinfo *pai; 790 const char *hostname; 791 const char *servname; 792 struct addrinfo **res; 793 { 794 #ifndef SCOPE_DELIMITER 795 return explore_numeric(pai, hostname, servname, res); 796 #else 797 const struct afd *afd; 798 struct addrinfo *cur; 799 int error; 800 char *cp, *hostname2 = NULL; 801 int scope; 802 struct sockaddr_in6 *sin6; 803 804 /* 805 * if the servname does not match socktype/protocol, ignore it. 806 */ 807 if (get_portmatch(pai, servname) != 0) 808 return 0; 809 810 afd = find_afd(pai->ai_family); 811 if (!afd->a_scoped) 812 return explore_numeric(pai, hostname, servname, res); 813 814 cp = strchr(hostname, SCOPE_DELIMITER); 815 if (cp == NULL) 816 return explore_numeric(pai, hostname, servname, res); 817 818 /* 819 * Handle special case of <scoped_address><delimiter><scope id> 820 */ 821 hostname2 = strdup(hostname); 822 if (hostname2 == NULL) 823 return EAI_MEMORY; 824 /* terminate at the delimiter */ 825 hostname2[cp - hostname] = '\0'; 826 827 cp++; 828 switch (pai->ai_family) { 829 #ifdef INET6 830 case AF_INET6: 831 scope = if_nametoindex(cp); 832 if (scope == 0) { 833 free(hostname2); 834 return (EAI_NONAME); 835 } 836 break; 837 #endif 838 } 839 840 error = explore_numeric(pai, hostname2, servname, res); 841 if (error == 0) { 842 for (cur = *res; cur; cur = cur->ai_next) { 843 if (cur->ai_family != AF_INET6) 844 continue; 845 sin6 = (struct sockaddr_in6 *)cur->ai_addr; 846 if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr) || 847 IN6_IS_ADDR_MC_LINKLOCAL(&sin6->sin6_addr)) 848 sin6->sin6_scope_id = scope; 849 } 850 } 851 852 free(hostname2); 853 854 return error; 855 #endif 856 } 857 858 static int 859 get_name(addr, afd, res, numaddr, pai, servname) 860 const char *addr; 861 const struct afd *afd; 862 struct addrinfo **res; 863 char *numaddr; 864 const struct addrinfo *pai; 865 const char *servname; 866 { 867 struct hostent *hp = NULL; 868 struct addrinfo *cur = NULL; 869 int error = 0; 870 char *ap = NULL, *cn = NULL; 871 #ifdef USE_GETIPNODEBY 872 int h_error; 873 874 hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error); 875 #else 876 hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af); 877 #endif 878 if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) { 879 #ifdef USE_GETIPNODEBY 880 GET_AI(cur, afd, hp->h_addr_list[0]); 881 GET_PORT(cur, servname); 882 GET_CANONNAME(cur, hp->h_name); 883 #else 884 /* hp will be damaged if we use gethostbyaddr() */ 885 if ((ap = (char *)malloc((size_t)hp->h_length)) == NULL) { 886 error = EAI_MEMORY; 887 goto free; 888 } 889 memcpy(ap, hp->h_addr_list[0], (size_t)hp->h_length); 890 if ((cn = strdup(hp->h_name)) == NULL) { 891 error = EAI_MEMORY; 892 goto free; 893 } 894 895 GET_AI(cur, afd, ap); 896 GET_PORT(cur, servname); 897 GET_CANONNAME(cur, cn); 898 free(ap); ap = NULL; 899 free(cn); cn = NULL; 900 #endif 901 } else { 902 GET_AI(cur, afd, numaddr); 903 GET_PORT(cur, servname); 904 } 905 906 #ifdef USE_GETIPNODEBY 907 if (hp) 908 freehostent(hp); 909 #endif 910 *res = cur; 911 return SUCCESS; 912 free: 913 if (cur) 914 freeaddrinfo(cur); 915 if (ap) 916 free(ap); 917 if (cn) 918 free(cn); 919 #ifdef USE_GETIPNODEBY 920 if (hp) 921 freehostent(hp); 922 #endif 923 *res = NULL; 924 return error; 925 } 926 927 static int 928 get_canonname(pai, ai, str) 929 const struct addrinfo *pai; 930 struct addrinfo *ai; 931 const char *str; 932 { 933 if ((pai->ai_flags & AI_CANONNAME) != 0) { 934 ai->ai_canonname = (char *)malloc(strlen(str) + 1); 935 if (ai->ai_canonname == NULL) 936 return EAI_MEMORY; 937 strcpy(ai->ai_canonname, str); 938 } 939 return 0; 940 } 941 942 static struct addrinfo * 943 get_ai(pai, afd, addr) 944 const struct addrinfo *pai; 945 const struct afd *afd; 946 const char *addr; 947 { 948 char *p; 949 struct addrinfo *ai; 950 951 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) 952 + (afd->a_socklen)); 953 if (ai == NULL) 954 return NULL; 955 956 memcpy(ai, pai, sizeof(struct addrinfo)); 957 ai->ai_addr = (struct sockaddr *)(ai + 1); 958 memset(ai->ai_addr, 0, (size_t)afd->a_socklen); 959 ai->ai_addr->sa_len = afd->a_socklen; 960 ai->ai_addrlen = afd->a_socklen; 961 ai->ai_addr->sa_family = ai->ai_family = afd->a_af; 962 p = (char *)(ai->ai_addr); 963 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); 964 return ai; 965 } 966 967 static int 968 get_portmatch(ai, servname) 969 const struct addrinfo *ai; 970 const char *servname; 971 { 972 973 /* get_port does not touch first argument. when matchonly == 1. */ 974 return get_port((struct addrinfo *)ai, servname, 1); 975 } 976 977 static int 978 get_port(ai, servname, matchonly) 979 struct addrinfo *ai; 980 const char *servname; 981 int matchonly; 982 { 983 const char *proto; 984 struct servent *sp; 985 int port; 986 int allownumeric; 987 988 if (servname == NULL) 989 return 0; 990 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) 991 return 0; 992 993 switch (ai->ai_socktype) { 994 case SOCK_RAW: 995 return EAI_SERVICE; 996 case SOCK_DGRAM: 997 case SOCK_STREAM: 998 allownumeric = 1; 999 break; 1000 case ANY: 1001 allownumeric = 0; 1002 break; 1003 default: 1004 return EAI_SOCKTYPE; 1005 } 1006 1007 if (str_isnumber(servname)) { 1008 if (!allownumeric) 1009 return EAI_SERVICE; 1010 port = htons(atoi(servname)); 1011 if (port < 0 || port > 65535) 1012 return EAI_SERVICE; 1013 } else { 1014 switch (ai->ai_socktype) { 1015 case SOCK_DGRAM: 1016 proto = "udp"; 1017 break; 1018 case SOCK_STREAM: 1019 proto = "tcp"; 1020 break; 1021 default: 1022 proto = NULL; 1023 break; 1024 } 1025 1026 if ((sp = getservbyname(servname, proto)) == NULL) 1027 return EAI_SERVICE; 1028 port = sp->s_port; 1029 } 1030 1031 if (!matchonly) { 1032 switch (ai->ai_family) { 1033 case AF_INET: 1034 ((struct sockaddr_in *)ai->ai_addr)->sin_port = port; 1035 break; 1036 #ifdef INET6 1037 case AF_INET6: 1038 ((struct sockaddr_in6 *)ai->ai_addr)->sin6_port = port; 1039 break; 1040 #endif 1041 } 1042 } 1043 1044 return 0; 1045 } 1046 1047 static const struct afd * 1048 find_afd(af) 1049 int af; 1050 { 1051 const struct afd *afd; 1052 1053 if (af == PF_UNSPEC) 1054 return NULL; 1055 for (afd = afdl; afd->a_af; afd++) { 1056 if (afd->a_af == af) 1057 return afd; 1058 } 1059 return NULL; 1060 } 1061
Indexes created Tue Sep 30 07:10:03 GMT 2025