lib/libc/net/gethostnamadr.c

   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 }