1 /*- 2 * Copyright (c) 1994, Garrett Wollman 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 * 25 * $FreeBSD: src/lib/libc/net/gethostnamadr.c,v 1.33 2006/05/21 11:27:28 ume Exp $ 26 */ 27 28 #include "namespace.h" 29 #include "reentrant.h" 30 #include <sys/param.h> 31 #include <sys/socket.h> 32 #include <netinet/in.h> 33 #include <arpa/inet.h> 34 #include <netdb.h> 35 #include <stdio.h> 36 #include <ctype.h> 37 #include <errno.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include <stdarg.h> 41 #include <nsswitch.h> 42 #include <arpa/nameser.h> /* XXX hack for _res */ 43 #include <resolv.h> /* XXX hack for _res */ 44 #include "un-namespace.h" 45 #include "netdb_private.h" 46 #ifdef NS_CACHING 47 #include "nscache.h" 48 #endif 49 50 static int gethostbyname_internal(const char *, int, struct hostent *, char *, 51 size_t, struct hostent **, int *, res_state); 52 53 /* Host lookup order if nsswitch.conf is broken or nonexistant */ 54 static const ns_src default_src[] = { 55 { NSSRC_FILES, NS_SUCCESS }, 56 { NSSRC_DNS, NS_SUCCESS }, 57 { 0 } 58 }; 59 #ifdef NS_CACHING 60 static int host_id_func(char *, size_t *, va_list, void *); 61 static int host_marshal_func(char *, size_t *, void *, va_list, void *); 62 static int host_unmarshal_func(char *, size_t, void *, va_list, void *); 63 #endif 64 65 NETDB_THREAD_ALLOC(hostent) 66 NETDB_THREAD_ALLOC(hostent_data) 67 NETDB_THREAD_ALLOC(hostdata) 68 69 static void 70 hostent_free(void *ptr) 71 { 72 free(ptr); 73 } 74 75 static void 76 hostent_data_free(void *ptr) 77 { 78 struct hostent_data *hed = ptr; 79 80 if (hed == NULL) 81 return; 82 hed->stayopen = 0; 83 _endhosthtent(hed); 84 free(hed); 85 } 86 87 static void 88 hostdata_free(void *ptr) 89 { 90 free(ptr); 91 } 92 93 int 94 __copy_hostent(struct hostent *he, struct hostent *hptr, char *buf, 95 size_t buflen) 96 { 97 char *cp; 98 char **ptr; 99 int i, n; 100 int nptr, len; 101 102 /* Find out the amount of space required to store the answer. */ 103 nptr = 2; /* NULL ptrs */ 104 len = (char *)ALIGN(buf) - buf; 105 for (i = 0; he->h_addr_list[i]; i++, nptr++) { 106 len += he->h_length; 107 } 108 for (i = 0; he->h_aliases[i]; i++, nptr++) { 109 len += strlen(he->h_aliases[i]) + 1; 110 } 111 len += strlen(he->h_name) + 1; 112 len += nptr * sizeof(char*); 113 114 if (len > buflen) { 115 errno = ERANGE; 116 return (-1); 117 } 118 119 /* copy address size and type */ 120 hptr->h_addrtype = he->h_addrtype; 121 n = hptr->h_length = he->h_length; 122 123 ptr = (char **)ALIGN(buf); 124 cp = (char *)ALIGN(buf) + nptr * sizeof(char *); 125 126 /* copy address list */ 127 hptr->h_addr_list = ptr; 128 for (i = 0; he->h_addr_list[i]; i++ , ptr++) { 129 memcpy(cp, he->h_addr_list[i], n); 130 hptr->h_addr_list[i] = cp; 131 cp += n; 132 } 133 hptr->h_addr_list[i] = NULL; 134 ptr++; 135 136 /* copy official name */ 137 n = strlen(he->h_name) + 1; 138 strcpy(cp, he->h_name); 139 hptr->h_name = cp; 140 cp += n; 141 142 /* copy aliases */ 143 hptr->h_aliases = ptr; 144 for (i = 0 ; he->h_aliases[i]; i++) { 145 n = strlen(he->h_aliases[i]) + 1; 146 strcpy(cp, he->h_aliases[i]); 147 hptr->h_aliases[i] = cp; 148 cp += n; 149 } 150 hptr->h_aliases[i] = NULL; 151 152 return (0); 153 } 154 155 #ifdef NS_CACHING 156 static int 157 host_id_func(char *buffer, size_t *buffer_size, va_list ap, void *cache_mdata) 158 { 159 res_state statp; 160 u_long res_options; 161 162 const int op_id = 1; 163 char *str; 164 void *addr; 165 socklen_t len; 166 int type; 167 168 size_t desired_size, size; 169 enum nss_lookup_type lookup_type; 170 char *p; 171 int res = NS_UNAVAIL; 172 173 statp = __res_state(); 174 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES | 175 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6); 176 177 lookup_type = (enum nss_lookup_type)cache_mdata; 178 switch (lookup_type) { 179 case nss_lt_name: 180 str = va_arg(ap, char *); 181 type = va_arg(ap, int); 182 183 size = strlen(str); 184 desired_size = sizeof(res_options) + sizeof(int) + 185 sizeof(enum nss_lookup_type) + sizeof(int) + size + 1; 186 187 if (desired_size > *buffer_size) { 188 res = NS_RETURN; 189 goto fin; 190 } 191 192 p = buffer; 193 194 memcpy(p, &res_options, sizeof(res_options)); 195 p += sizeof(res_options); 196 197 memcpy(p, &op_id, sizeof(int)); 198 p += sizeof(int); 199 200 memcpy(p, &lookup_type, sizeof(enum nss_lookup_type)); 201 p += sizeof(int); 202 203 memcpy(p, &type, sizeof(int)); 204 p += sizeof(int); 205 206 memcpy(p, str, size + 1); 207 208 res = NS_SUCCESS; 209 break; 210 case nss_lt_id: 211 addr = va_arg(ap, void *); 212 len = va_arg(ap, socklen_t); 213 type = va_arg(ap, int); 214 215 desired_size = sizeof(res_options) + sizeof(int) + 216 sizeof(enum nss_lookup_type) + sizeof(int) + 217 sizeof(socklen_t) + len; 218 219 if (desired_size > *buffer_size) { 220 res = NS_RETURN; 221 goto fin; 222 } 223 224 p = buffer; 225 memcpy(p, &res_options, sizeof(res_options)); 226 p += sizeof(res_options); 227 228 memcpy(p, &op_id, sizeof(int)); 229 p += sizeof(int); 230 231 memcpy(p, &lookup_type, sizeof(enum nss_lookup_type)); 232 p += sizeof(int); 233 234 memcpy(p, &type, sizeof(int)); 235 p += sizeof(int); 236 237 memcpy(p, &len, sizeof(socklen_t)); 238 p += sizeof(socklen_t); 239 240 memcpy(p, addr, len); 241 242 res = NS_SUCCESS; 243 break; 244 default: 245 /* should be unreachable */ 246 return (NS_UNAVAIL); 247 } 248 249 fin: 250 *buffer_size = desired_size; 251 return (res); 252 } 253 254 static int 255 host_marshal_func(char *buffer, size_t *buffer_size, void *retval __unused, 256 va_list ap, void *cache_mdata) 257 { 258 char *str __unused; 259 void *addr __unused; 260 socklen_t len __unused; 261 int type __unused; 262 struct hostent *ht; 263 264 struct hostent new_ht; 265 size_t desired_size, aliases_size, addr_size, size; 266 char *p, **iter; 267 268 switch ((enum nss_lookup_type)cache_mdata) { 269 case nss_lt_name: 270 str = va_arg(ap, char *); 271 type = va_arg(ap, int); 272 break; 273 case nss_lt_id: 274 addr = va_arg(ap, void *); 275 len = va_arg(ap, socklen_t); 276 type = va_arg(ap, int); 277 break; 278 default: 279 /* should be unreachable */ 280 return (NS_UNAVAIL); 281 } 282 ht = va_arg(ap, struct hostent *); 283 284 desired_size = _ALIGNBYTES + sizeof(struct hostent) + sizeof(char *); 285 if (ht->h_name != NULL) 286 desired_size += strlen(ht->h_name) + 1; 287 288 if (ht->h_aliases != NULL) { 289 aliases_size = 0; 290 for (iter = ht->h_aliases; *iter; ++iter) { 291 desired_size += strlen(*iter) + 1; 292 ++aliases_size; 293 } 294 295 desired_size += _ALIGNBYTES + 296 (aliases_size + 1) * sizeof(char *); 297 } 298 299 if (ht->h_addr_list != NULL) { 300 addr_size = 0; 301 for (iter = ht->h_addr_list; *iter; ++iter) 302 ++addr_size; 303 304 desired_size += addr_size * _ALIGN(ht->h_length); 305 desired_size += _ALIGNBYTES + (addr_size + 1) * sizeof(char *); 306 } 307 308 if (desired_size > *buffer_size) { 309 /* this assignment is here for future use */ 310 *buffer_size = desired_size; 311 return (NS_RETURN); 312 } 313 314 memcpy(&new_ht, ht, sizeof(struct hostent)); 315 memset(buffer, 0, desired_size); 316 317 *buffer_size = desired_size; 318 p = buffer + sizeof(struct hostent) + sizeof(char *); 319 memcpy(buffer + sizeof(struct hostent), &p, sizeof(char *)); 320 p = (char *)_ALIGN(p); 321 322 if (new_ht.h_name != NULL) { 323 size = strlen(new_ht.h_name); 324 memcpy(p, new_ht.h_name, size); 325 new_ht.h_name = p; 326 p += size + 1; 327 } 328 329 if (new_ht.h_aliases != NULL) { 330 p = (char *)_ALIGN(p); 331 memcpy(p, new_ht.h_aliases, sizeof(char *) * aliases_size); 332 new_ht.h_aliases = (char **)p; 333 p += sizeof(char *) * (aliases_size + 1); 334 335 for (iter = new_ht.h_aliases; *iter; ++iter) { 336 size = strlen(*iter); 337 memcpy(p, *iter, size); 338 *iter = p; 339 p += size + 1; 340 } 341 } 342 343 if (new_ht.h_addr_list != NULL) { 344 p = (char *)_ALIGN(p); 345 memcpy(p, new_ht.h_addr_list, sizeof(char *) * addr_size); 346 new_ht.h_addr_list = (char **)p; 347 p += sizeof(char *) * (addr_size + 1); 348 349 size = _ALIGN(new_ht.h_length); 350 for (iter = new_ht.h_addr_list; *iter; ++iter) { 351 memcpy(p, *iter, size); 352 *iter = p; 353 p += size + 1; 354 } 355 } 356 memcpy(buffer, &new_ht, sizeof(struct hostent)); 357 return (NS_SUCCESS); 358 } 359 360 static int 361 host_unmarshal_func(char *buffer, size_t buffer_size, void *retval, va_list ap, 362 void *cache_mdata) 363 { 364 char *str __unused; 365 void *addr __unused; 366 socklen_t len __unused; 367 int type __unused; 368 struct hostent *ht; 369 370 char *p; 371 char **iter; 372 char *orig_buf; 373 size_t orig_buf_size; 374 375 switch ((enum nss_lookup_type)cache_mdata) { 376 case nss_lt_name: 377 str = va_arg(ap, char *); 378 type = va_arg(ap, int); 379 break; 380 case nss_lt_id: 381 addr = va_arg(ap, void *); 382 len = va_arg(ap, socklen_t); 383 type = va_arg(ap, int); 384 break; 385 default: 386 /* should be unreachable */ 387 return (NS_UNAVAIL); 388 } 389 390 ht = va_arg(ap, struct hostent *); 391 orig_buf = va_arg(ap, char *); 392 orig_buf_size = va_arg(ap, size_t); 393 394 if (orig_buf_size < 395 buffer_size - sizeof(struct hostent) - sizeof(char *)) { 396 errno = ERANGE; 397 return (NS_RETURN); 398 } 399 400 memcpy(ht, buffer, sizeof(struct hostent)); 401 memcpy(&p, buffer + sizeof(struct hostent), sizeof(char *)); 402 403 orig_buf = (char *)_ALIGN(orig_buf); 404 memcpy(orig_buf, buffer + sizeof(struct hostent) + sizeof(char *) + 405 _ALIGN(p) - (size_t)p, 406 buffer_size - sizeof(struct hostent) - sizeof(char *) - 407 _ALIGN(p) + (size_t)p); 408 p = (char *)_ALIGN(p); 409 410 NS_APPLY_OFFSET(ht->h_name, orig_buf, p, char *); 411 if (ht->h_aliases != NULL) { 412 NS_APPLY_OFFSET(ht->h_aliases, orig_buf, p, char **); 413 414 for (iter = ht->h_aliases; *iter; ++iter) 415 NS_APPLY_OFFSET(*iter, orig_buf, p, char *); 416 } 417 418 if (ht->h_addr_list != NULL) { 419 NS_APPLY_OFFSET(ht->h_addr_list, orig_buf, p, char **); 420 421 for (iter = ht->h_addr_list; *iter; ++iter) 422 NS_APPLY_OFFSET(*iter, orig_buf, p, char *); 423 } 424 425 *((struct hostent **)retval) = ht; 426 return (NS_SUCCESS); 427 } 428 #endif /* NS_CACHING */ 429 430 static int 431 fakeaddr(const char *name, int af, struct hostent *hp, char *buf, 432 size_t buflen, res_state statp) 433 { 434 struct hostent_data *hed; 435 struct hostent he; 436 437 if ((hed = __hostent_data_init()) == NULL) { 438 errno = ENOMEM; 439 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 440 return (-1); 441 } 442 443 if ((af != AF_INET || 444 inet_aton(name, (struct in_addr *)hed->host_addr) != 1) && 445 inet_pton(af, name, hed->host_addr) != 1) { 446 RES_SET_H_ERRNO(statp, HOST_NOT_FOUND); 447 return (-1); 448 } 449 strncpy(hed->hostbuf, name, MAXDNAME); 450 hed->hostbuf[MAXDNAME] = '\0'; 451 if (af == AF_INET && (statp->options & RES_USE_INET6) != 0U) { 452 _map_v4v6_address((char *)hed->host_addr, 453 (char *)hed->host_addr); 454 af = AF_INET6; 455 } 456 he.h_addrtype = af; 457 switch(af) { 458 case AF_INET: 459 he.h_length = NS_INADDRSZ; 460 break; 461 case AF_INET6: 462 he.h_length = NS_IN6ADDRSZ; 463 break; 464 default: 465 errno = EAFNOSUPPORT; 466 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 467 return (-1); 468 } 469 he.h_name = hed->hostbuf; 470 he.h_aliases = hed->host_aliases; 471 hed->host_aliases[0] = NULL; 472 hed->h_addr_ptrs[0] = (char *)hed->host_addr; 473 hed->h_addr_ptrs[1] = NULL; 474 he.h_addr_list = hed->h_addr_ptrs; 475 RES_SET_H_ERRNO(statp, NETDB_SUCCESS); 476 return (__copy_hostent(&he, hp, buf, buflen)); 477 } 478 479 int 480 gethostbyname_r(const char *name, struct hostent *he, char *buffer, 481 size_t buflen, struct hostent **result, int *h_errnop) 482 { 483 res_state statp; 484 485 statp = __res_state(); 486 if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) { 487 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 488 return (-1); 489 } 490 if (statp->options & RES_USE_INET6) { 491 if (fakeaddr(name, AF_INET, he, buffer, buflen, statp) == 0) { 492 *result = he; 493 return (0); 494 } 495 if (gethostbyname_internal(name, AF_INET6, he, buffer, buflen, 496 result, h_errnop, statp) == 0) 497 return (0); 498 } 499 return (gethostbyname_internal(name, AF_INET, he, buffer, buflen, 500 result, h_errnop, statp)); 501 } 502 503 int 504 gethostbyname2_r(const char *name, int af, struct hostent *he, char *buffer, 505 size_t buflen, struct hostent **result, int *h_errnop) 506 { 507 res_state statp; 508 509 statp = __res_state(); 510 if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) { 511 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 512 return (-1); 513 } 514 return (gethostbyname_internal(name, af, he, buffer, buflen, result, 515 h_errnop, statp)); 516 } 517 518 static int 519 gethostbyname_internal(const char *name, int af, struct hostent *hp, char *buf, 520 size_t buflen, struct hostent **result, int *h_errnop, 521 res_state statp) 522 { 523 const char *cp; 524 int rval, ret_errno; 525 char abuf[MAXDNAME]; 526 527 #ifdef NS_CACHING 528 static const nss_cache_info cache_info = 529 NS_COMMON_CACHE_INFO_INITIALIZER( 530 hosts, (void *)nss_lt_name, 531 host_id_func, host_marshal_func, host_unmarshal_func); 532 #endif 533 static const ns_dtab dtab[] = { 534 NS_FILES_CB(_ht_gethostbyname, NULL) 535 { NSSRC_DNS, _dns_gethostbyname, NULL }, 536 NS_NIS_CB(_nis_gethostbyname, NULL) /* force -DHESIOD */ 537 #ifdef NS_CACHING 538 NS_CACHE_CB(&cache_info) 539 #endif 540 { 0 } 541 }; 542 543 switch (af) { 544 case AF_INET: 545 case AF_INET6: 546 break; 547 default: 548 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 549 *h_errnop = statp->res_h_errno; 550 errno = EAFNOSUPPORT; 551 return (-1); 552 } 553 554 /* 555 * if there aren't any dots, it could be a user-level alias. 556 * this is also done in res_query() since we are not the only 557 * function that looks up host names. 558 */ 559 if (!strchr(name, '.') && 560 (cp = res_hostalias(statp, name, abuf, sizeof abuf))) 561 name = cp; 562 563 if (fakeaddr(name, af, hp, buf, buflen, statp) == 0) { 564 *result = hp; 565 return (0); 566 } 567 568 rval = _nsdispatch((void *)result, dtab, NSDB_HOSTS, 569 "gethostbyname2_r", default_src, name, af, hp, buf, buflen, 570 &ret_errno, h_errnop); 571 572 return ((rval == NS_SUCCESS) ? 0 : -1); 573 } 574 575 int 576 gethostbyaddr_r(const void *addr, socklen_t len, int af, struct hostent *hp, 577 char *buf, size_t buflen, struct hostent **result, 578 int *h_errnop) 579 { 580 const u_char *uaddr = (const u_char *)addr; 581 const struct in6_addr *addr6; 582 socklen_t size; 583 int rval, ret_errno; 584 res_state statp; 585 586 #ifdef NS_CACHING 587 static const nss_cache_info cache_info = 588 NS_COMMON_CACHE_INFO_INITIALIZER( 589 hosts, (void *)nss_lt_id, 590 host_id_func, host_marshal_func, host_unmarshal_func); 591 #endif 592 static const ns_dtab dtab[] = { 593 NS_FILES_CB(_ht_gethostbyaddr, NULL) 594 { NSSRC_DNS, _dns_gethostbyaddr, NULL }, 595 NS_NIS_CB(_nis_gethostbyaddr, NULL) /* force -DHESIOD */ 596 #ifdef NS_CACHING 597 NS_CACHE_CB(&cache_info) 598 #endif 599 { 0 } 600 }; 601 602 statp = __res_state(); 603 if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) { 604 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 605 *h_errnop = statp->res_h_errno; 606 return (-1); 607 } 608 609 if (af == AF_INET6 && len == NS_IN6ADDRSZ) { 610 addr6 = (const struct in6_addr *)addr; 611 if (IN6_IS_ADDR_LINKLOCAL(addr6)) { 612 RES_SET_H_ERRNO(statp, HOST_NOT_FOUND); 613 *h_errnop = statp->res_h_errno; 614 return (-1); 615 } 616 if (IN6_IS_ADDR_V4MAPPED(addr6) || 617 IN6_IS_ADDR_V4COMPAT(addr6)) { 618 /* Unmap. */ 619 uaddr += NS_IN6ADDRSZ - NS_INADDRSZ; 620 af = AF_INET; 621 len = NS_INADDRSZ; 622 } 623 } 624 switch (af) { 625 case AF_INET: 626 size = NS_INADDRSZ; 627 break; 628 case AF_INET6: 629 size = NS_IN6ADDRSZ; 630 break; 631 default: 632 errno = EAFNOSUPPORT; 633 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 634 *h_errnop = statp->res_h_errno; 635 return (-1); 636 } 637 if (size != len) { 638 errno = EINVAL; 639 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 640 *h_errnop = statp->res_h_errno; 641 return (-1); 642 } 643 644 rval = _nsdispatch((void *)result, dtab, NSDB_HOSTS, 645 "gethostbyaddr_r", default_src, uaddr, len, af, hp, buf, buflen, 646 &ret_errno, h_errnop); 647 648 return ((rval == NS_SUCCESS) ? 0 : -1); 649 } 650 651 struct hostent * 652 gethostbyname(const char *name) 653 { 654 struct hostdata *hd; 655 struct hostent *rval; 656 int ret_h_errno; 657 658 if ((hd = __hostdata_init()) == NULL) 659 return (NULL); 660 if (gethostbyname_r(name, &hd->host, hd->data, sizeof(hd->data), &rval, 661 &ret_h_errno) != 0) 662 return (NULL); 663 return (rval); 664 } 665 666 struct hostent * 667 gethostbyname2(const char *name, int af) 668 { 669 struct hostdata *hd; 670 struct hostent *rval; 671 int ret_h_errno; 672 673 if ((hd = __hostdata_init()) == NULL) 674 return (NULL); 675 if (gethostbyname2_r(name, af, &hd->host, hd->data, sizeof(hd->data), 676 &rval, &ret_h_errno) != 0) 677 return (NULL); 678 return (rval); 679 } 680 681 struct hostent * 682 gethostbyaddr(const void *addr, socklen_t len, int af) 683 { 684 struct hostdata *hd; 685 struct hostent *rval; 686 int ret_h_errno; 687 688 if ((hd = __hostdata_init()) == NULL) 689 return (NULL); 690 if (gethostbyaddr_r(addr, len, af, &hd->host, hd->data, 691 sizeof(hd->data), &rval, &ret_h_errno) != 0) 692 return (NULL); 693 return (rval); 694 } 695 696 void 697 sethostent(int stayopen) 698 { 699 struct hostent_data *hed; 700 701 if ((hed = __hostent_data_init()) == NULL) 702 return; 703 _sethosthtent(stayopen, hed); 704 _sethostdnsent(stayopen); 705 } 706 707 void 708 endhostent(void) 709 { 710 struct hostent_data *hed; 711 712 if ((hed = __hostent_data_init()) == NULL) 713 return; 714 _endhosthtent(hed); 715 _endhostdnsent(); 716 } 717