lib/libc/net/gethnamaddr.c

   1 /*      $NetBSD: gethnamaddr.c,v 1.79 2012/09/09 16:42:23 christos Exp $        */
   2
   3 /*
   4  * ++Copyright++ 1985, 1988, 1993
   5  * -
   6  * Copyright (c) 1985, 1988, 1993
   7  *    The Regents of the University of California.  All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  * -
  33  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
  34  *
  35  * Permission to use, copy, modify, and distribute this software for any
  36  * purpose with or without fee is hereby granted, provided that the above
  37  * copyright notice and this permission notice appear in all copies, and that
  38  * the name of Digital Equipment Corporation not be used in advertising or
  39  * publicity pertaining to distribution of the document or software without
  40  * specific, written prior permission.
  41  *
  42  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
  43  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
  44  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
  45  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  46  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  47  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  48  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  49  * SOFTWARE.
  50  * -
  51  * --Copyright--
  52  */
  53
  54 #include <sys/cdefs.h>
  55 #if defined(LIBC_SCCS) && !defined(lint)
  56 #if 0
  57 static char sccsid[] = "@(#)gethostnamadr.c     8.1 (Berkeley) 6/4/93";
  58 static char rcsid[] = "Id: gethnamaddr.c,v 8.21 1997/06/01 20:34:37 vixie Exp ";
  59 #else
  60 __RCSID("$NetBSD: gethnamaddr.c,v 1.79 2012/09/09 16:42:23 christos Exp $");
  61 #endif
  62 #endif /* LIBC_SCCS and not lint */
  63
  64 #if defined(_LIBC)
  65 #include "namespace.h"
  66 #endif
  67 #include <sys/param.h>
  68 #include <sys/socket.h>
  69 #include <netinet/in.h>
  70 #include <arpa/inet.h>
  71 #include <arpa/nameser.h>
  72
  73 #include <assert.h>
  74 #include <ctype.h>
  75 #include <errno.h>
  76 #include <netdb.h>
  77 #include <resolv.h>
  78 #include <stdarg.h>
  79 #include <stdio.h>
  80 #include <syslog.h>
  81
  82 #ifndef LOG_AUTH
  83 # define LOG_AUTH 0
  84 #endif
  85
  86 #define MULTI_PTRS_ARE_ALIASES 1        /* XXX - experimental */
  87
  88 #include <nsswitch.h>
  89 #include <stdlib.h>
  90 #include <string.h>
  91
  92 #ifdef YP
  93 #include <rpc/rpc.h>
  94 #include <rpcsvc/yp_prot.h>
  95 #include <rpcsvc/ypclnt.h>
  96 #endif
  97
  98 #if defined(_LIBC) && defined(__weak_alias)
  99 __weak_alias(gethostbyaddr,_gethostbyaddr)
 100 __weak_alias(gethostbyname,_gethostbyname)
 101 __weak_alias(gethostent,_gethostent)
 102 #endif
 103
 104 #define maybe_ok(res, nm, ok) (((res)->options & RES_NOCHECKNAME) != 0U || \
 105                                (ok)(nm) != 0)
 106 #define maybe_hnok(res, hn) maybe_ok((res), (hn), res_hnok)
 107 #define maybe_dnok(res, dn) maybe_ok((res), (dn), res_dnok)
 108
 109
 110 #define MAXALIASES      35
 111 #define MAXADDRS        35
 112
 113 static const char AskedForGot[] =
 114                           "gethostby*.getanswer: asked for \"%s\", got \"%s\"";
 115
 116 static char *h_addr_ptrs[MAXADDRS + 1];
 117
 118 #ifdef YP
 119 static char *__ypdomain;
 120 #endif
 121
 122 static struct hostent host;
 123 static char *host_aliases[MAXALIASES];
 124 static char hostbuf[8*1024];
 125 static u_int32_t host_addr[16 / sizeof(u_int32_t)];     /* IPv4 or IPv6 */
 126 static FILE *hostf = NULL;
 127 static int stayopen = 0;
 128
 129 #define MAXPACKET       (64*1024)
 130
 131 typedef union {
 132     HEADER hdr;
 133     u_char buf[MAXPACKET];
 134 } querybuf;
 135
 136 typedef union {
 137     int32_t al;
 138     char ac;
 139 } align;
 140
 141 #ifdef DEBUG
 142 static void debugprintf(const char *, res_state, ...)
 143         __attribute__((__format__(__printf__, 1, 3)));
 144 #endif
 145 static struct hostent *getanswer(const querybuf *, int, const char *, int,
 146     res_state);
 147 static void map_v4v6_address(const char *, char *);
 148 static void map_v4v6_hostent(struct hostent *, char **, char *);
 149 static void addrsort(char **, int, res_state);
 150
 151 void _sethtent(int);
 152 void _endhtent(void);
 153 struct hostent *_gethtent(void);
 154 void ht_sethostent(int);
 155 void ht_endhostent(void);
 156 struct hostent *ht_gethostbyname(char *);
 157 struct hostent *ht_gethostbyaddr(const char *, int, int);
 158 void dns_service(void);
 159 #undef dn_skipname
 160 int dn_skipname(const u_char *, const u_char *);
 161 int _gethtbyaddr(void *, void *, va_list);
 162 int _gethtbyname(void *, void *, va_list);
 163 struct hostent *_gethtbyname2(const char *, int);
 164 int _dns_gethtbyaddr(void *, void *, va_list);
 165 int _dns_gethtbyname(void *, void *, va_list);
 166 #ifdef YP
 167 struct hostent *_yphostent(char *, int);
 168 int _yp_gethtbyaddr(void *, void *, va_list);
 169 int _yp_gethtbyname(void *, void *, va_list);
 170 #endif
 171
 172 static struct hostent *gethostbyname_internal(const char *, int, res_state);
 173
 174 static const ns_src default_dns_files[] = {
 175         { NSSRC_FILES,  NS_SUCCESS },
 176         { NSSRC_DNS,    NS_SUCCESS },
 177         { 0, 0 }
 178 };
 179
 180
 181 #ifdef DEBUG
 182 static void
 183 debugprintf(const char *msg, res_state res, ...)
 184 {
 185         _DIAGASSERT(msg != NULL);
 186
 187         if (res->options & RES_DEBUG) {
 188                 int save = errno;
 189                 va_list ap;
 190
 191                 va_start (ap, res);
 192                 vprintf(msg, ap);
 193                 va_end (ap);
 194
 195                 errno = save;
 196         }
 197 }
 198 #else
 199 # define debugprintf(msg, res, num) /*nada*/
 200 #endif
 201
 202 #define BOUNDED_INCR(x) \
 203         do { \
 204                 cp += (x); \
 205                 if (cp > eom) { \
 206                         h_errno = NO_RECOVERY; \
 207                         return NULL; \
 208                 } \
 209         } while (/*CONSTCOND*/0)
 210
 211 #define BOUNDS_CHECK(ptr, count) \
 212         do { \
 213                 if ((ptr) + (count) > eom) { \
 214                         h_errno = NO_RECOVERY; \
 215                         return NULL; \
 216                 } \
 217         } while (/*CONSTCOND*/0)
 218
 219 static struct hostent *
 220 getanswer(const querybuf *answer, int anslen, const char *qname, int qtype,
 221     res_state res)
 222 {
 223         const HEADER *hp;
 224         const u_char *cp;
 225         int n;
 226         const u_char *eom, *erdata;
 227         char *bp, **ap, **hap, *ep;
 228         int type, class, ancount, qdcount;
 229         int haveanswer, had_error;
 230         int toobig = 0;
 231         char tbuf[MAXDNAME];
 232         const char *tname;
 233         int (*name_ok)(const char *);
 234
 235         _DIAGASSERT(answer != NULL);
 236         _DIAGASSERT(qname != NULL);
 237
 238         tname = qname;
 239         host.h_name = NULL;
 240         eom = answer->buf + anslen;
 241         switch (qtype) {
 242         case T_A:
 243         case T_AAAA:
 244                 name_ok = res_hnok;
 245                 break;
 246         case T_PTR:
 247                 name_ok = res_dnok;
 248                 break;
 249         default:
 250                 return NULL;    /* XXX should be abort(); */
 251         }
 252         /*
 253          * find first satisfactory answer
 254          */
 255         hp = &answer->hdr;
 256         ancount = ntohs(hp->ancount);
 257         qdcount = ntohs(hp->qdcount);
 258         bp = hostbuf;
 259         ep = hostbuf + sizeof hostbuf;
 260         cp = answer->buf;
 261         BOUNDED_INCR(HFIXEDSZ);
 262         if (qdcount != 1) {
 263                 h_errno = NO_RECOVERY;
 264                 return NULL;
 265         }
 266         n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp));
 267         if ((n < 0) || !maybe_ok(res, bp, name_ok)) {
 268                 h_errno = NO_RECOVERY;
 269                 return NULL;
 270         }
 271         BOUNDED_INCR(n + QFIXEDSZ);
 272         if (qtype == T_A || qtype == T_AAAA) {
 273                 /* res_send() has already verified that the query name is the
 274                  * same as the one we sent; this just gets the expanded name
 275                  * (i.e., with the succeeding search-domain tacked on).
 276                  */
 277                 n = (int)strlen(bp) + 1;                /* for the \0 */
 278                 if (n >= MAXHOSTNAMELEN) {
 279                         h_errno = NO_RECOVERY;
 280                         return NULL;
 281                 }
 282                 host.h_name = bp;
 283                 bp += n;
 284                 /* The qname can be abbreviated, but h_name is now absolute. */
 285                 qname = host.h_name;
 286         }
 287         ap = host_aliases;
 288         *ap = NULL;
 289         host.h_aliases = host_aliases;
 290         hap = h_addr_ptrs;
 291         *hap = NULL;
 292         host.h_addr_list = h_addr_ptrs;
 293         haveanswer = 0;
 294         had_error = 0;
 295         while (ancount-- > 0 && cp < eom && !had_error) {
 296                 n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp));
 297                 if ((n < 0) || !maybe_ok(res, bp, name_ok)) {
 298                         had_error++;
 299                         continue;
 300                 }
 301                 cp += n;                        /* name */
 302                 BOUNDS_CHECK(cp, 3 * INT16SZ + INT32SZ);
 303                 type = _getshort(cp);
 304                 cp += INT16SZ;                  /* type */
 305                 class = _getshort(cp);
 306                 cp += INT16SZ + INT32SZ;        /* class, TTL */
 307                 n = _getshort(cp);
 308                 cp += INT16SZ;                  /* len */
 309                 BOUNDS_CHECK(cp, n);
 310                 erdata = cp + n;
 311                 if (class != C_IN) {
 312                         /* XXX - debug? syslog? */
 313                         cp += n;
 314                         continue;               /* XXX - had_error++ ? */
 315                 }
 316                 if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME) {
 317                         if (ap >= &host_aliases[MAXALIASES-1])
 318                                 continue;
 319                         n = dn_expand(answer->buf, eom, cp, tbuf, (int)sizeof tbuf);
 320                         if ((n < 0) || !maybe_ok(res, tbuf, name_ok)) {
 321                                 had_error++;
 322                                 continue;
 323                         }
 324                         cp += n;
 325                         if (cp != erdata) {
 326                                 h_errno = NO_RECOVERY;
 327                                 return NULL;
 328                         }
 329                         /* Store alias. */
 330                         *ap++ = bp;
 331                         n = (int)strlen(bp) + 1;        /* for the \0 */
 332                         if (n >= MAXHOSTNAMELEN) {
 333                                 had_error++;
 334                                 continue;
 335                         }
 336                         bp += n;
 337                         /* Get canonical name. */
 338                         n = (int)strlen(tbuf) + 1;      /* for the \0 */
 339                         if (n > ep - bp || n >= MAXHOSTNAMELEN) {
 340                                 had_error++;
 341                                 continue;
 342                         }
 343                         strlcpy(bp, tbuf, (size_t)(ep - bp));
 344                         host.h_name = bp;
 345                         bp += n;
 346                         continue;
 347                 }
 348                 if (qtype == T_PTR && type == T_CNAME) {
 349                         n = dn_expand(answer->buf, eom, cp, tbuf, (int)sizeof tbuf);
 350                         if (n < 0 || !maybe_dnok(res, tbuf)) {
 351                                 had_error++;
 352                                 continue;
 353                         }
 354                         cp += n;
 355                         if (cp != erdata) {
 356                                 h_errno = NO_RECOVERY;
 357                                 return NULL;
 358                         }
 359                         /* Get canonical name. */
 360                         n = (int)strlen(tbuf) + 1;      /* for the \0 */
 361                         if (n > ep - bp || n >= MAXHOSTNAMELEN) {
 362                                 had_error++;
 363                                 continue;
 364                         }
 365                         strlcpy(bp, tbuf, (size_t)(ep - bp));
 366                         tname = bp;
 367                         bp += n;
 368                         continue;
 369                 }
 370                 if (type != qtype) {
 371                         if (type != T_KEY && type != T_SIG)
 372                                 syslog(LOG_NOTICE|LOG_AUTH,
 373                "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
 374                                        qname, p_class(C_IN), p_type(qtype),
 375                                        p_type(type));
 376                         cp += n;
 377                         continue;               /* XXX - had_error++ ? */
 378                 }
 379                 switch (type) {
 380                 case T_PTR:
 381                         if (strcasecmp(tname, bp) != 0) {
 382                                 syslog(LOG_NOTICE|LOG_AUTH,
 383                                        AskedForGot, qname, bp);
 384                                 cp += n;
 385                                 continue;       /* XXX - had_error++ ? */
 386                         }
 387                         n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp));
 388                         if ((n < 0) || !maybe_hnok(res, bp)) {
 389                                 had_error++;
 390                                 break;
 391                         }
 392 #if MULTI_PTRS_ARE_ALIASES
 393                         cp += n;
 394                         if (cp != erdata) {
 395                                 h_errno = NO_RECOVERY;
 396                                 return NULL;
 397                         }
 398                         if (!haveanswer)
 399                                 host.h_name = bp;
 400                         else if (ap < &host_aliases[MAXALIASES-1])
 401                                 *ap++ = bp;
 402                         else
 403                                 n = -1;
 404                         if (n != -1) {
 405                                 n = (int)strlen(bp) + 1;        /* for the \0 */
 406                                 if (n >= MAXHOSTNAMELEN) {
 407                                         had_error++;
 408                                         break;
 409                                 }
 410                                 bp += n;
 411                         }
 412                         break;
 413 #else
 414                         host.h_name = bp;
 415                         if (res->options & RES_USE_INET6) {
 416                                 n = strlen(bp) + 1;     /* for the \0 */
 417                                 if (n >= MAXHOSTNAMELEN) {
 418                                         had_error++;
 419                                         break;
 420                                 }
 421                                 bp += n;
 422                                 map_v4v6_hostent(&host, &bp, ep);
 423                         }
 424                         h_errno = NETDB_SUCCESS;
 425                         return &host;
 426 #endif
 427                 case T_A:
 428                 case T_AAAA:
 429                         if (strcasecmp(host.h_name, bp) != 0) {
 430                                 syslog(LOG_NOTICE|LOG_AUTH,
 431                                        AskedForGot, host.h_name, bp);
 432                                 cp += n;
 433                                 continue;       /* XXX - had_error++ ? */
 434                         }
 435                         if (n != host.h_length) {
 436                                 cp += n;
 437                                 continue;
 438                         }
 439                         if (type == T_AAAA) {
 440                                 struct in6_addr in6;
 441                                 memcpy(&in6, cp, IN6ADDRSZ);
 442                                 if (IN6_IS_ADDR_V4MAPPED(&in6)) {
 443                                         cp += n;
 444                                         continue;
 445                                 }
 446                         }
 447                         if (!haveanswer) {
 448                                 int nn;
 449
 450                                 host.h_name = bp;
 451                                 nn = (int)strlen(bp) + 1;       /* for the \0 */
 452                                 bp += nn;
 453                         }
 454
 455                         bp += sizeof(align) -
 456                             (size_t)((u_long)bp % sizeof(align));
 457
 458                         if (bp + n >= &hostbuf[sizeof hostbuf]) {
 459                                 debugprintf("size (%d) too big\n", res, n);
 460                                 had_error++;
 461                                 continue;
 462                         }
 463                         if (hap >= &h_addr_ptrs[MAXADDRS-1]) {
 464                                 if (!toobig++) {
 465                                         debugprintf("Too many addresses (%d)\n",
 466                                                 res, MAXADDRS);
 467                                 }
 468                                 cp += n;
 469                                 continue;
 470                         }
 471                         (void)memcpy(*hap++ = bp, cp, (size_t)n);
 472                         bp += n;
 473                         cp += n;
 474                         if (cp != erdata) {
 475                                 h_errno = NO_RECOVERY;
 476                                 return NULL;
 477                         }
 478                         break;
 479                 default:
 480                         abort();
 481                 }
 482                 if (!had_error)
 483                         haveanswer++;
 484         }
 485         if (haveanswer) {
 486                 *ap = NULL;
 487                 *hap = NULL;
 488                 /*
 489                  * Note: we sort even if host can take only one address
 490                  * in its return structures - should give it the "best"
 491                  * address in that case, not some random one
 492                  */
 493                 if (res->nsort && haveanswer > 1 && qtype == T_A)
 494                         addrsort(h_addr_ptrs, haveanswer, res);
 495                 if (!host.h_name) {
 496                         n = (int)strlen(qname) + 1;     /* for the \0 */
 497                         if (n > ep - bp || n >= MAXHOSTNAMELEN)
 498                                 goto no_recovery;
 499                         strlcpy(bp, qname, (size_t)(ep - bp));
 500                         host.h_name = bp;
 501                         bp += n;
 502                 }
 503                 if (res->options & RES_USE_INET6)
 504                         map_v4v6_hostent(&host, &bp, ep);
 505                 h_errno = NETDB_SUCCESS;
 506                 return &host;
 507         }
 508  no_recovery:
 509         h_errno = NO_RECOVERY;
 510         return NULL;
 511 }
 512
 513 struct hostent *
 514 gethostbyname(const char *name)
 515 {
 516         struct hostent *hp;
 517         res_state res = __res_get_state();
 518
 519         if (res == NULL)
 520                 return NULL;
 521
 522         _DIAGASSERT(name != NULL);
 523
 524         if (res->options & RES_USE_INET6) {
 525                 hp = gethostbyname_internal(name, AF_INET6, res);
 526                 if (hp) {
 527                         __res_put_state(res);
 528                         return hp;
 529                 }
 530         }
 531         hp = gethostbyname_internal(name, AF_INET, res);
 532         __res_put_state(res);
 533         return hp;
 534 }
 535
 536 struct hostent *
 537 gethostbyname2(const char *name, int af)
 538 {
 539         struct hostent *hp;
 540         res_state res = __res_get_state();
 541
 542         if (res == NULL)
 543                 return NULL;
 544         hp = gethostbyname_internal(name, af, res);
 545         __res_put_state(res);
 546         return hp;
 547 }
 548
 549 static struct hostent *
 550 gethostbyname_internal(const char *name, int af, res_state res)
 551 {
 552         const char *cp;
 553         char *bp, *ep;
 554         int size;
 555         struct hostent *hp;
 556         static const ns_dtab dtab[] = {
 557                 NS_FILES_CB(_gethtbyname, NULL)
 558                 { NSSRC_DNS, _dns_gethtbyname, NULL },  /* force -DHESIOD */
 559                 NS_NIS_CB(_yp_gethtbyname, NULL)
 560                 NS_NULL_CB
 561         };
 562
 563         _DIAGASSERT(name != NULL);
 564
 565         switch (af) {
 566         case AF_INET:
 567                 size = INADDRSZ;
 568                 break;
 569         case AF_INET6:
 570                 size = IN6ADDRSZ;
 571                 break;
 572         default:
 573                 h_errno = NETDB_INTERNAL;
 574                 errno = EAFNOSUPPORT;
 575                 return NULL;
 576         }
 577
 578         host.h_addrtype = af;
 579         host.h_length = size;
 580
 581         /*
 582          * if there aren't any dots, it could be a user-level alias.
 583          * this is also done in res_nquery() since we are not the only
 584          * function that looks up host names.
 585          */
 586         if (!strchr(name, '.') && (cp = __hostalias(name)))
 587                 name = cp;
 588
 589         /*
 590          * disallow names consisting only of digits/dots, unless
 591          * they end in a dot.
 592          */
 593         if (isdigit((u_char) name[0]))
 594                 for (cp = name;; ++cp) {
 595                         if (!*cp) {
 596                                 if (*--cp == '.')
 597                                         break;
 598                                 /*
 599                                  * All-numeric, no dot at the end.
 600                                  * Fake up a hostent as if we'd actually
 601                                  * done a lookup.
 602                                  */
 603                                 if (inet_pton(af, name,
 604                                     (char *)(void *)host_addr) <= 0) {
 605                                         h_errno = HOST_NOT_FOUND;
 606                                         return NULL;
 607                                 }
 608                                 strncpy(hostbuf, name, MAXDNAME);
 609                                 hostbuf[MAXDNAME] = '\0';
 610                                 bp = hostbuf + MAXDNAME;
 611                                 ep = hostbuf + sizeof hostbuf;
 612                                 host.h_name = hostbuf;
 613                                 host.h_aliases = host_aliases;
 614                                 host_aliases[0] = NULL;
 615                                 h_addr_ptrs[0] = (char *)(void *)host_addr;
 616                                 h_addr_ptrs[1] = NULL;
 617                                 host.h_addr_list = h_addr_ptrs;
 618                                 if (res->options & RES_USE_INET6)
 619                                         map_v4v6_hostent(&host, &bp, ep);
 620                                 h_errno = NETDB_SUCCESS;
 621                                 return &host;
 622                         }
 623                         if (!isdigit((u_char) *cp) && *cp != '.')
 624                                 break;
 625                 }
 626         if ((isxdigit((u_char) name[0]) && strchr(name, ':') != NULL) ||
 627             name[0] == ':')
 628                 for (cp = name;; ++cp) {
 629                         if (!*cp) {
 630                                 if (*--cp == '.')
 631                                         break;
 632                                 /*
 633                                  * All-IPv6-legal, no dot at the end.
 634                                  * Fake up a hostent as if we'd actually
 635                                  * done a lookup.
 636                                  */
 637                                 if (inet_pton(af, name,
 638                                     (char *)(void *)host_addr) <= 0) {
 639                                         h_errno = HOST_NOT_FOUND;
 640                                         return NULL;
 641                                 }
 642                                 strncpy(hostbuf, name, MAXDNAME);
 643                                 hostbuf[MAXDNAME] = '\0';
 644                                 bp = hostbuf + MAXDNAME;
 645                                 ep = hostbuf + sizeof hostbuf;
 646                                 host.h_name = hostbuf;
 647                                 host.h_aliases = host_aliases;
 648                                 host_aliases[0] = NULL;
 649                                 h_addr_ptrs[0] = (char *)(void *)host_addr;
 650                                 h_addr_ptrs[1] = NULL;
 651                                 host.h_addr_list = h_addr_ptrs;
 652                                 h_errno = NETDB_SUCCESS;
 653                                 return &host;
 654                         }
 655                         if (!isxdigit((u_char) *cp) && *cp != ':' && *cp != '.')
 656                                 break;
 657                 }
 658
 659         hp = NULL;
 660         h_errno = NETDB_INTERNAL;
 661         if (nsdispatch(&hp, dtab, NSDB_HOSTS, "gethostbyname",
 662             default_dns_files, name, strlen(name), af) != NS_SUCCESS)
 663                 return NULL;
 664         h_errno = NETDB_SUCCESS;
 665         return hp;
 666 }
 667
 668 struct hostent *
 669 gethostbyaddr(const char *addr, /* XXX should have been def'd as u_char! */
 670     socklen_t len, int af)
 671 {
 672         const u_char *uaddr = (const u_char *)addr;
 673         socklen_t size;
 674         struct hostent *hp;
 675         static const ns_dtab dtab[] = {
 676                 NS_FILES_CB(_gethtbyaddr, NULL)
 677                 { NSSRC_DNS, _dns_gethtbyaddr, NULL },  /* force -DHESIOD */
 678                 NS_NIS_CB(_yp_gethtbyaddr, NULL)
 679                 NS_NULL_CB
 680         };
 681
 682         _DIAGASSERT(addr != NULL);
 683
 684         if (af == AF_INET6 && len == IN6ADDRSZ &&
 685             (IN6_IS_ADDR_LINKLOCAL((const struct in6_addr *)(const void *)uaddr) ||
 686              IN6_IS_ADDR_SITELOCAL((const struct in6_addr *)(const void *)uaddr))) {
 687                 h_errno = HOST_NOT_FOUND;
 688                 return NULL;
 689         }
 690         if (af == AF_INET6 && len == IN6ADDRSZ &&
 691             (IN6_IS_ADDR_V4MAPPED((const struct in6_addr *)(const void *)uaddr) ||
 692              IN6_IS_ADDR_V4COMPAT((const struct in6_addr *)(const void *)uaddr))) {
 693                 /* Unmap. */
 694                 addr += IN6ADDRSZ - INADDRSZ;
 695                 uaddr += IN6ADDRSZ - INADDRSZ;
 696                 af = AF_INET;
 697                 len = INADDRSZ;
 698         }
 699         switch (af) {
 700         case AF_INET:
 701                 size = INADDRSZ;
 702                 break;
 703         case AF_INET6:
 704                 size = IN6ADDRSZ;
 705                 break;
 706         default:
 707                 errno = EAFNOSUPPORT;
 708                 h_errno = NETDB_INTERNAL;
 709                 return NULL;
 710         }
 711         if (size != len) {
 712                 errno = EINVAL;
 713                 h_errno = NETDB_INTERNAL;
 714                 return NULL;
 715         }
 716         hp = NULL;
 717         h_errno = NETDB_INTERNAL;
 718         if (nsdispatch(&hp, dtab, NSDB_HOSTS, "gethostbyaddr",
 719             default_dns_files, uaddr, len, af) != NS_SUCCESS)
 720                 return NULL;
 721         h_errno = NETDB_SUCCESS;
 722         return hp;
 723 }
 724
 725 void
 726 _sethtent(int f)
 727 {
 728         if (!hostf)
 729                 hostf = fopen(_PATH_HOSTS, "re");
 730         else
 731                 rewind(hostf);
 732         stayopen = f;
 733 }
 734
 735 void
 736 _endhtent(void)
 737 {
 738         if (hostf && !stayopen) {
 739                 (void) fclose(hostf);
 740                 hostf = NULL;
 741         }
 742 }
 743
 744 struct hostent *
 745 _gethtent(void)
 746 {
 747         char *p;
 748         char *cp, **q;
 749         int af, len;
 750
 751         if (!hostf && !(hostf = fopen(_PATH_HOSTS, "re"))) {
 752                 h_errno = NETDB_INTERNAL;
 753                 return NULL;
 754         }
 755  again:
 756         if (!(p = fgets(hostbuf, (int)sizeof hostbuf, hostf))) {
 757                 h_errno = HOST_NOT_FOUND;
 758                 return NULL;
 759         }
 760         if (*p == '#')
 761                 goto again;
 762         if (!(cp = strpbrk(p, "#\n")))
 763                 goto again;
 764         *cp = '\0';
 765         if (!(cp = strpbrk(p, " \t")))
 766                 goto again;
 767         *cp++ = '\0';
 768         if (inet_pton(AF_INET6, p, (char *)(void *)host_addr) > 0) {
 769                 af = AF_INET6;
 770                 len = IN6ADDRSZ;
 771         } else if (inet_pton(AF_INET, p, (char *)(void *)host_addr) > 0) {
 772                 res_state res = __res_get_state();
 773                 if (res == NULL)
 774                         return NULL;
 775                 if (res->options & RES_USE_INET6) {
 776                         map_v4v6_address((char *)(void *)host_addr,
 777                             (char *)(void *)host_addr);
 778                         af = AF_INET6;
 779                         len = IN6ADDRSZ;
 780                 } else {
 781                         af = AF_INET;
 782                         len = INADDRSZ;
 783                 }
 784                 __res_put_state(res);
 785         } else {
 786                 goto again;
 787         }
 788         /* if this is not something we're looking for, skip it. */
 789         if (host.h_addrtype != 0 && host.h_addrtype != af)
 790                 goto again;
 791         if (host.h_length != 0 && host.h_length != len)
 792                 goto again;
 793         h_addr_ptrs[0] = (char *)(void *)host_addr;
 794         h_addr_ptrs[1] = NULL;
 795         host.h_addr_list = h_addr_ptrs;
 796         host.h_length = len;
 797         host.h_addrtype = af;
 798         while (*cp == ' ' || *cp == '\t')
 799                 cp++;
 800         host.h_name = cp;
 801         q = host.h_aliases = host_aliases;
 802         if ((cp = strpbrk(cp, " \t")) != NULL)
 803                 *cp++ = '\0';
 804         while (cp && *cp) {
 805                 if (*cp == ' ' || *cp == '\t') {
 806                         cp++;
 807                         continue;
 808                 }
 809                 if (q < &host_aliases[MAXALIASES - 1])
 810                         *q++ = cp;
 811                 if ((cp = strpbrk(cp, " \t")) != NULL)
 812                         *cp++ = '\0';
 813         }
 814         *q = NULL;
 815         h_errno = NETDB_SUCCESS;
 816         return &host;
 817 }
 818
 819 /*ARGSUSED*/
 820 int
 821 _gethtbyname(void *rv, void *cb_data, va_list ap)
 822 {
 823         struct hostent *hp;
 824         const char *name;
 825         int af;
 826
 827         _DIAGASSERT(rv != NULL);
 828
 829         name = va_arg(ap, char *);
 830         /* NOSTRICT skip len */(void)va_arg(ap, int);
 831         af = va_arg(ap, int);
 832
 833         hp = NULL;
 834 #if 0
 835         {
 836                 res_state res = __res_get_state();
 837                 if (res == NULL)
 838                         return NS_NOTFOUND;
 839                 if (res->options & RES_USE_INET6)
 840                         hp = _gethtbyname2(name, AF_INET6);
 841                 if (hp==NULL)
 842                         hp = _gethtbyname2(name, AF_INET);
 843                 __res_put_state(res);
 844         }
 845 #else
 846         hp = _gethtbyname2(name, af);
 847 #endif
 848         *((struct hostent **)rv) = hp;
 849         if (hp == NULL) {
 850                 h_errno = HOST_NOT_FOUND;
 851                 return NS_NOTFOUND;
 852         }
 853         return NS_SUCCESS;
 854 }
 855
 856 struct hostent *
 857 _gethtbyname2(const char *name, int af)
 858 {
 859         struct hostent *p;
 860         char *tmpbuf, *ptr, **cp;
 861         int num;
 862         size_t len;
 863
 864         _DIAGASSERT(name != NULL);
 865
 866         _sethtent(stayopen);
 867         ptr = tmpbuf = NULL;
 868         num = 0;
 869         while ((p = _gethtent()) != NULL && num < MAXADDRS) {
 870                 if (p->h_addrtype != af)
 871                         continue;
 872                 if (strcasecmp(p->h_name, name) != 0) {
 873                         for (cp = p->h_aliases; *cp != NULL; cp++)
 874                                 if (strcasecmp(*cp, name) == 0)
 875                                         break;
 876                         if (*cp == NULL) continue;
 877                 }
 878
 879                 if (num == 0) {
 880                         size_t bufsize;
 881                         char *src;
 882
 883                         bufsize = strlen(p->h_name) + 2 +
 884                                   MAXADDRS * p->h_length +
 885                                   ALIGNBYTES;
 886                         for (cp = p->h_aliases; *cp != NULL; cp++)
 887                                 bufsize += strlen(*cp) + 1;
 888
 889                         if ((tmpbuf = malloc(bufsize)) == NULL) {
 890                                 h_errno = NETDB_INTERNAL;
 891                                 return NULL;
 892                         }
 893
 894                         ptr = tmpbuf;
 895                         src = p->h_name;
 896                         while ((*ptr++ = *src++) != '\0');
 897                         for (cp = p->h_aliases; *cp != NULL; cp++) {
 898                                 src = *cp;
 899                                 while ((*ptr++ = *src++) != '\0');
 900                         }
 901                         *ptr++ = '\0';
 902
 903                         ptr = (char *)(void *)ALIGN(ptr);
 904                 }
 905
 906                 (void)memcpy(ptr, p->h_addr_list[0], (size_t)p->h_length);
 907                 ptr += p->h_length;
 908                 num++;
 909         }
 910         _endhtent();
 911         if (num == 0) return NULL;
 912
 913         len = ptr - tmpbuf;
 914         if (len > (sizeof(hostbuf) - ALIGNBYTES)) {
 915                 free(tmpbuf);
 916                 errno = ENOSPC;
 917                 h_errno = NETDB_INTERNAL;
 918                 return NULL;
 919         }
 920         ptr = memcpy((void *)ALIGN(hostbuf), tmpbuf, len);
 921         free(tmpbuf);
 922
 923         host.h_name = ptr;
 924         while (*ptr++);
 925
 926         cp = host_aliases;
 927         while (*ptr) {
 928                 *cp++ = ptr;
 929                 while (*ptr++);
 930         }
 931         ptr++;
 932         *cp = NULL;
 933
 934         ptr = (char *)(void *)ALIGN(ptr);
 935         cp = h_addr_ptrs;
 936         while (num--) {
 937                 *cp++ = ptr;
 938                 ptr += host.h_length;
 939         }
 940         *cp = NULL;
 941
 942         return &host;
 943 }
 944
 945 /*ARGSUSED*/
 946 int
 947 _gethtbyaddr(void *rv, void *cb_data, va_list ap)
 948 {
 949         struct hostent *p;
 950         const unsigned char *addr;
 951         int len, af;
 952
 953         _DIAGASSERT(rv != NULL);
 954
 955         addr = va_arg(ap, unsigned char *);
 956         len = va_arg(ap, int);
 957         af = va_arg(ap, int);
 958
 959         host.h_length = len;
 960         host.h_addrtype = af;
 961
 962         _sethtent(stayopen);
 963         while ((p = _gethtent()) != NULL)
 964                 if (p->h_addrtype == af && !memcmp(p->h_addr, addr,
 965                     (size_t)len))
 966                         break;
 967         _endhtent();
 968         *((struct hostent **)rv) = p;
 969         if (p==NULL) {
 970                 h_errno = HOST_NOT_FOUND;
 971                 return NS_NOTFOUND;
 972         }
 973         return NS_SUCCESS;
 974 }
 975
 976 static void
 977 map_v4v6_address(const char *src, char *dst)
 978 {
 979         u_char *p = (u_char *)dst;
 980         char tmp[INADDRSZ];
 981         int i;
 982
 983         _DIAGASSERT(src != NULL);
 984         _DIAGASSERT(dst != NULL);
 985
 986         /* Stash a temporary copy so our caller can update in place. */
 987         (void)memcpy(tmp, src, INADDRSZ);
 988         /* Mark this ipv6 addr as a mapped ipv4. */
 989         for (i = 0; i < 10; i++)
 990                 *p++ = 0x00;
 991         *p++ = 0xff;
 992         *p++ = 0xff;
 993         /* Retrieve the saved copy and we're done. */
 994         (void)memcpy((void *)p, tmp, INADDRSZ);
 995 }
 996
 997 static void
 998 map_v4v6_hostent(struct hostent *hp, char **bpp, char *ep)
 999 {
1000         char **ap;
1001
1002         _DIAGASSERT(hp != NULL);
1003         _DIAGASSERT(bpp != NULL);
1004         _DIAGASSERT(ep != NULL);
1005
1006         if (hp->h_addrtype != AF_INET || hp->h_length != INADDRSZ)
1007                 return;
1008         hp->h_addrtype = AF_INET6;
1009         hp->h_length = IN6ADDRSZ;
1010         for (ap = hp->h_addr_list; *ap; ap++) {
1011                 int i = (int)(sizeof(align) -
1012                     (size_t)((u_long)*bpp % sizeof(align)));
1013
1014                 if (ep - *bpp < (i + IN6ADDRSZ)) {
1015                         /* Out of memory.  Truncate address list here.  XXX */
1016                         *ap = NULL;
1017                         return;
1018                 }
1019                 *bpp += i;
1020                 map_v4v6_address(*ap, *bpp);
1021                 *ap = *bpp;
1022                 *bpp += IN6ADDRSZ;
1023         }
1024 }
1025
1026 static void
1027 addrsort(char **ap, int num, res_state res)
1028 {
1029         int i, j;
1030         char **p;
1031         short aval[MAXADDRS];
1032         int needsort = 0;
1033
1034         _DIAGASSERT(ap != NULL);
1035
1036         p = ap;
1037         for (i = 0; i < num; i++, p++) {
1038             for (j = 0 ; (unsigned)j < res->nsort; j++)
1039                 if (res->sort_list[j].addr.s_addr ==
1040                     (((struct in_addr *)(void *)(*p))->s_addr &
1041                     res->sort_list[j].mask))
1042                         break;
1043             aval[i] = j;
1044             if (needsort == 0 && i > 0 && j < aval[i-1])
1045                 needsort = i;
1046         }
1047         if (!needsort)
1048             return;
1049
1050         while (needsort < num) {
1051             for (j = needsort - 1; j >= 0; j--) {
1052                 if (aval[j] > aval[j+1]) {
1053                     char *hp;
1054
1055                     i = aval[j];
1056                     aval[j] = aval[j+1];
1057                     aval[j+1] = i;
1058
1059                     hp = ap[j];
1060                     ap[j] = ap[j+1];
1061                     ap[j+1] = hp;
1062                 } else
1063                     break;
1064             }
1065             needsort++;
1066         }
1067 }
1068
1069 struct hostent *
1070 gethostent(void)
1071 {
1072         host.h_addrtype = 0;
1073         host.h_length = 0;
1074         return _gethtent();
1075 }
1076
1077 /*ARGSUSED*/
1078 int
1079 _dns_gethtbyname(void *rv, void *cb_data, va_list ap)
1080 {
1081         querybuf *buf;
1082         int n, type;
1083         struct hostent *hp;
1084         const char *name;
1085         int af;
1086         res_state res;
1087
1088         _DIAGASSERT(rv != NULL);
1089
1090         name = va_arg(ap, char *);
1091         /* NOSTRICT skip len */(void)va_arg(ap, int);
1092         af = va_arg(ap, int);
1093
1094         switch (af) {
1095         case AF_INET:
1096                 type = T_A;
1097                 break;
1098         case AF_INET6:
1099                 type = T_AAAA;
1100                 break;
1101         default:
1102                 return NS_UNAVAIL;
1103         }
1104         buf = malloc(sizeof(*buf));
1105         if (buf == NULL) {
1106                 h_errno = NETDB_INTERNAL;
1107                 return NS_NOTFOUND;
1108         }
1109         res = __res_get_state();
1110         if (res == NULL) {
1111                 free(buf);
1112                 return NS_NOTFOUND;
1113         }
1114         n = res_nsearch(res, name, C_IN, type, buf->buf, (int)sizeof(buf->buf));
1115         if (n < 0) {
1116                 free(buf);
1117                 debugprintf("res_nsearch failed (%d)\n", res, n);
1118                 __res_put_state(res);
1119                 return NS_NOTFOUND;
1120         }
1121         hp = getanswer(buf, n, name, type, res);
1122         free(buf);
1123         __res_put_state(res);
1124         if (hp == NULL)
1125                 switch (h_errno) {
1126                 case HOST_NOT_FOUND:
1127                         return NS_NOTFOUND;
1128                 case TRY_AGAIN:
1129                         return NS_TRYAGAIN;
1130                 default:
1131                         return NS_UNAVAIL;
1132                 }
1133         *((struct hostent **)rv) = hp;
1134         return NS_SUCCESS;
1135 }
1136
1137 /*ARGSUSED*/
1138 int
1139 _dns_gethtbyaddr(void *rv, void *cb_data, va_list ap)
1140 {
1141         char qbuf[MAXDNAME + 1], *qp, *ep;
1142         int n;
1143         querybuf *buf;
1144         struct hostent *hp;
1145         const unsigned char *uaddr;
1146         int len, af, advance;
1147         res_state res;
1148
1149         _DIAGASSERT(rv != NULL);
1150
1151         uaddr = va_arg(ap, unsigned char *);
1152         len = va_arg(ap, int);
1153         af = va_arg(ap, int);
1154
1155         switch (af) {
1156         case AF_INET:
1157                 (void)snprintf(qbuf, sizeof(qbuf), "%u.%u.%u.%u.in-addr.arpa",
1158                     (uaddr[3] & 0xff), (uaddr[2] & 0xff),
1159                     (uaddr[1] & 0xff), (uaddr[0] & 0xff));
1160                 break;
1161
1162         case AF_INET6:
1163                 qp = qbuf;
1164                 ep = qbuf + sizeof(qbuf) - 1;
1165                 for (n = IN6ADDRSZ - 1; n >= 0; n--) {
1166                         advance = snprintf(qp, (size_t)(ep - qp), "%x.%x.",
1167                             uaddr[n] & 0xf,
1168                             ((unsigned int)uaddr[n] >> 4) & 0xf);
1169                         if (advance > 0 && qp + advance < ep)
1170                                 qp += advance;
1171                         else {
1172                                 h_errno = NETDB_INTERNAL;
1173                                 return NS_NOTFOUND;
1174                         }
1175                 }
1176                 if (strlcat(qbuf, "ip6.arpa", sizeof(qbuf)) >= sizeof(qbuf)) {
1177                         h_errno = NETDB_INTERNAL;
1178                         return NS_NOTFOUND;
1179                 }
1180                 break;
1181         default:
1182                 abort();
1183         }
1184
1185         buf = malloc(sizeof(*buf));
1186         if (buf == NULL) {
1187                 h_errno = NETDB_INTERNAL;
1188                 return NS_NOTFOUND;
1189         }
1190         res = __res_get_state();
1191         if (res == NULL) {
1192                 free(buf);
1193                 return NS_NOTFOUND;
1194         }
1195         n = res_nquery(res, qbuf, C_IN, T_PTR, buf->buf, (int)sizeof(buf->buf));
1196         if (n < 0) {
1197                 free(buf);
1198                 debugprintf("res_nquery failed (%d)\n", res, n);
1199                 __res_put_state(res);
1200                 return NS_NOTFOUND;
1201         }
1202         hp = getanswer(buf, n, qbuf, T_PTR, res);
1203         free(buf);
1204         if (hp == NULL) {
1205                 __res_put_state(res);
1206                 switch (h_errno) {
1207                 case HOST_NOT_FOUND:
1208                         return NS_NOTFOUND;
1209                 case TRY_AGAIN:
1210                         return NS_TRYAGAIN;
1211                 default:
1212                         return NS_UNAVAIL;
1213                 }
1214         }
1215         hp->h_addrtype = af;
1216         hp->h_length = len;
1217         (void)memcpy(host_addr, uaddr, (size_t)len);
1218         h_addr_ptrs[0] = (char *)(void *)host_addr;
1219         h_addr_ptrs[1] = NULL;
1220         if (af == AF_INET && (res->options & RES_USE_INET6)) {
1221                 map_v4v6_address((char *)(void *)host_addr,
1222                     (char *)(void *)host_addr);
1223                 hp->h_addrtype = AF_INET6;
1224                 hp->h_length = IN6ADDRSZ;
1225         }
1226
1227         __res_put_state(res);
1228         *((struct hostent **)rv) = hp;
1229         h_errno = NETDB_SUCCESS;
1230         return NS_SUCCESS;
1231 }
1232
1233 #ifdef YP
1234 /*ARGSUSED*/
1235 struct hostent *
1236 _yphostent(char *line, int af)
1237 {
1238         static struct in_addr host_addrs[MAXADDRS];
1239         static struct in6_addr host6_addrs[MAXADDRS];
1240         char *p = line;
1241         char *cp, **q;
1242         char **hap;
1243         int addrok;
1244         int more;
1245         size_t naddrs;
1246
1247         _DIAGASSERT(line != NULL);
1248
1249         host.h_name = NULL;
1250         host.h_addr_list = h_addr_ptrs;
1251         host.h_addrtype = af;
1252         switch (af) {
1253         case AF_INET:
1254                 host.h_length = INADDRSZ;
1255                 break;
1256         case AF_INET6:
1257                 host.h_length = IN6ADDRSZ;
1258                 break;
1259         default:
1260                 return NULL;
1261         }
1262         hap = h_addr_ptrs;
1263         q = host.h_aliases = host_aliases;
1264         naddrs = 0;
1265
1266 nextline:
1267         /* check for host_addrs overflow */
1268         if (naddrs >= sizeof(host_addrs) / sizeof(host_addrs[0]))
1269                 goto done;
1270         if (naddrs >= sizeof(host6_addrs) / sizeof(host6_addrs[0]))
1271                 goto done;
1272
1273         more = 0;
1274         cp = strpbrk(p, " \t");
1275         if (cp == NULL)
1276                 goto done;
1277         *cp++ = '\0';
1278
1279         /* p has should have an address */
1280         addrok = 0;
1281         switch (af) {
1282         case AF_INET:
1283                 addrok = inet_aton(p, &host_addrs[naddrs]);
1284                 break;
1285         case AF_INET6:
1286                 addrok = inet_pton(af, p, &host6_addrs[naddrs]);
1287                 break;
1288         }
1289         if (addrok != 1) {
1290                 /* skip to the next line */
1291                 while (cp && *cp) {
1292                         if (*cp == '\n') {
1293                                 cp++;
1294                                 goto nextline;
1295                         }
1296                         cp++;
1297                 }
1298
1299                 goto done;
1300         }
1301
1302         switch (af) {
1303         case AF_INET:
1304                 *hap++ = (char *)(void *)&host_addrs[naddrs++];
1305                 break;
1306         case AF_INET6:
1307                 *hap++ = (char *)(void *)&host6_addrs[naddrs++];
1308                 break;
1309         }
1310
1311         while (*cp == ' ' || *cp == '\t')
1312                 cp++;
1313         p = cp;
1314         cp = strpbrk(p, " \t\n");
1315         if (cp != NULL) {
1316                 if (*cp == '\n')
1317                         more = 1;
1318                 *cp++ = '\0';
1319         }
1320         if (!host.h_name)
1321                 host.h_name = p;
1322         else if (strcmp(host.h_name, p)==0)
1323                 ;
1324         else if (q < &host_aliases[MAXALIASES - 1])
1325                 *q++ = p;
1326         p = cp;
1327         if (more)
1328                 goto nextline;
1329
1330         while (cp && *cp) {
1331                 if (*cp == ' ' || *cp == '\t') {
1332                         cp++;
1333                         continue;
1334                 }
1335                 if (*cp == '\n') {
1336                         cp++;
1337                         goto nextline;
1338                 }
1339                 if (q < &host_aliases[MAXALIASES - 1])
1340                         *q++ = cp;
1341                 cp = strpbrk(cp, " \t");
1342                 if (cp != NULL)
1343                         *cp++ = '\0';
1344         }
1345
1346 done:
1347         if (host.h_name == NULL)
1348                 return NULL;
1349         *q = NULL;
1350         *hap = NULL;
1351         return &host;
1352 }
1353
1354 /*ARGSUSED*/
1355 int
1356 _yp_gethtbyaddr(void *rv, void *cb_data, va_list ap)
1357 {
1358         struct hostent *hp = NULL;
1359         static char *__ypcurrent;
1360         int __ypcurrentlen, r;
1361         char name[INET6_ADDRSTRLEN];    /* XXX enough? */
1362         const unsigned char *uaddr;
1363         int af;
1364         const char *map;
1365
1366         _DIAGASSERT(rv != NULL);
1367
1368         uaddr = va_arg(ap, unsigned char *);
1369         /* NOSTRICT skip len */(void)va_arg(ap, int);
1370         af = va_arg(ap, int);
1371
1372         if (!__ypdomain) {
1373                 if (_yp_check(&__ypdomain) == 0)
1374                         return NS_UNAVAIL;
1375         }
1376         /*
1377          * XXX unfortunately, we cannot support IPv6 extended scoped address
1378          * notation here.  gethostbyaddr() is not scope-aware.  too bad.
1379          */
1380         if (inet_ntop(af, uaddr, name, (socklen_t)sizeof(name)) == NULL)
1381                 return NS_UNAVAIL;
1382         if (__ypcurrent)
1383                 free(__ypcurrent);
1384         __ypcurrent = NULL;
1385         switch (af) {
1386         case AF_INET:
1387                 map = "hosts.byaddr";
1388                 break;
1389         default:
1390                 map = "ipnodes.byaddr";
1391                 break;
1392         }
1393         r = yp_match(__ypdomain, map, name,
1394                 (int)strlen(name), &__ypcurrent, &__ypcurrentlen);
1395         if (r == 0)
1396                 hp = _yphostent(__ypcurrent, af);
1397         if (hp == NULL) {
1398                 h_errno = HOST_NOT_FOUND;
1399                 return NS_NOTFOUND;
1400         }
1401         *((struct hostent **)rv) = hp;
1402         return NS_SUCCESS;
1403 }
1404
1405 /*ARGSUSED*/
1406 int
1407 _yp_gethtbyname(void *rv, void *cb_data, va_list ap)
1408 {
1409         struct hostent *hp = NULL;
1410         static char *__ypcurrent;
1411         int __ypcurrentlen, r;
1412         const char *name;
1413         int af;
1414         const char *map;
1415
1416         _DIAGASSERT(rv != NULL);
1417
1418         name = va_arg(ap, char *);
1419         /* NOSTRICT skip len */(void)va_arg(ap, int);
1420         af = va_arg(ap, int);
1421
1422         if (!__ypdomain) {
1423                 if (_yp_check(&__ypdomain) == 0)
1424                         return NS_UNAVAIL;
1425         }
1426         if (__ypcurrent)
1427                 free(__ypcurrent);
1428         __ypcurrent = NULL;
1429         switch (af) {
1430         case AF_INET:
1431                 map = "hosts.byname";
1432                 break;
1433         default:
1434                 map = "ipnodes.byname";
1435                 break;
1436         }
1437         r = yp_match(__ypdomain, map, name,
1438                 (int)strlen(name), &__ypcurrent, &__ypcurrentlen);
1439         if (r == 0)
1440                 hp = _yphostent(__ypcurrent, af);
1441         if (hp == NULL) {
1442                 h_errno = HOST_NOT_FOUND;
1443                 return NS_NOTFOUND;
1444         }
1445         *((struct hostent **)rv) = hp;
1446         return NS_SUCCESS;
1447 }
1448 #endif