resolv/res_init.c

   1 /*
   2  * ++Copyright++ 1985, 1989, 1993
   3  * -
   4  * Copyright (c) 1985, 1989, 1993
   5  *    The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by the University of
  18  *      California, Berkeley and its contributors.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  * -
  35  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
  36  *
  37  * Permission to use, copy, modify, and distribute this software for any
  38  * purpose with or without fee is hereby granted, provided that the above
  39  * copyright notice and this permission notice appear in all copies, and that
  40  * the name of Digital Equipment Corporation not be used in advertising or
  41  * publicity pertaining to distribution of the document or software without
  42  * specific, written prior permission.
  43  *
  44  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
  45  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
  46  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
  47  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  48  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  49  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  50  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  51  * SOFTWARE.
  52  * -
  53  * --Copyright--
  54  */
  55
  56 #if defined(LIBC_SCCS) && !defined(lint)
  57 static char sccsid[] = "@(#)res_init.c  8.1 (Berkeley) 6/7/93";
  58 static char rcsid[] = "$Id$";
  59 #endif /* LIBC_SCCS and not lint */
  60
  61 #include <sys/types.h>
  62 #include <sys/param.h>
  63 #include <sys/socket.h>
  64 #include <sys/time.h>
  65 #include <netinet/in.h>
  66 #include <arpa/inet.h>
  67 #include <arpa/nameser.h>
  68
  69 #include <stdio.h>
  70 #include <ctype.h>
  71 #include <resolv.h>
  72 #if defined(BSD) && (BSD >= 199103)
  73 # include <unistd.h>
  74 # include <stdlib.h>
  75 # include <string.h>
  76 #else
  77 # include "../conf/portability.h"
  78 #endif
  79
  80 /*-------------------------------------- info about "sortlist" --------------
  81  * Marc Majka           1994/04/16
  82  * Allan Nathanson      1994/10/29 (BIND 4.9.3.x)
  83  *
  84  * NetInfo resolver configuration directory support.
  85  *
  86  * Allow a NetInfo directory to be created in the hierarchy which
  87  * contains the same information as the resolver configuration file.
  88  *
  89  * - The local domain name is stored as the value of the "domain" property.
  90  * - The Internet address(es) of the name server(s) are stored as values
  91  *   of the "nameserver" property.
  92  * - The name server addresses are stored as values of the "nameserver"
  93  *   property.
  94  * - The search list for host-name lookup is stored as values of the
  95  *   "search" property.
  96  * - The sortlist comprised of IP address netmask pairs are stored as
  97  *   values of the "sortlist" property. The IP address and optional netmask
  98  *   should be seperated by a slash (/) or ampersand (&) character.
  99  * - Internal resolver variables can be set from the value of the "options"
 100  *   property.
 101  */
 102 #if defined(NeXT)
 103 #  include <netinfo/ni.h>
 104 #  define NI_PATH_RESCONF "/locations/resolver"
 105 #  define NI_TIMEOUT 10
 106 static int netinfo_res_init __P((int *haveenv, int *havesearch));
 107 #endif
 108
 109 #if defined(USE_OPTIONS_H)
 110 # include "../conf/options.h"
 111 #endif
 112
 113 static void res_setoptions __P((char *, char *));
 114
 115 #ifdef RESOLVSORT
 116 static const char sort_mask[] = "/&";
 117 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
 118 static u_int32_t net_mask __P((struct in_addr));
 119 #endif
 120
 121 #if !defined(isascii)   /* XXX - could be a function */
 122 # define isascii(c) (!(c & 0200))
 123 #endif
 124
 125 /*
 126  * Resolver state default settings.
 127  */
 128
 129 struct __res_state _res
 130 # if defined(__BIND_RES_TEXT)
 131         = { RES_TIMEOUT, }      /* Motorola, et al. */
 132 # endif
 133         ;
 134
 135 /*
 136  * Set up default settings.  If the configuration file exist, the values
 137  * there will have precedence.  Otherwise, the server address is set to
 138  * INADDR_ANY and the default domain name comes from the gethostname().
 139  *
 140  * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
 141  * rather than INADDR_ANY ("0.0.0.0") as the default name server address
 142  * since it was noted that INADDR_ANY actually meant ``the first interface
 143  * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
 144  * it had to be "up" in order for you to reach your own name server.  It
 145  * was later decided that since the recommended practice is to always
 146  * install local static routes through 127.0.0.1 for all your network
 147  * interfaces, that we could solve this problem without a code change.
 148  *
 149  * The configuration file should always be used, since it is the only way
 150  * to specify a default domain.  If you are running a server on your local
 151  * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
 152  * in the configuration file.
 153  *
 154  * Return 0 if completes successfully, -1 on error
 155  */
 156 int
 157 res_init()
 158 {
 159         register FILE *fp;
 160         register char *cp, **pp;
 161         register int n;
 162         char buf[BUFSIZ];
 163         int nserv = 0;    /* number of nameserver records read from file */
 164         int haveenv = 0;
 165         int havesearch = 0;
 166 #ifdef RESOLVSORT
 167         int nsort = 0;
 168         char *net;
 169 #endif
 170 #ifndef RFC1535
 171         int dots;
 172 #endif
 173
 174         /*
 175          * These three fields used to be statically initialized.  This made
 176          * it hard to use this code in a shared library.  It is necessary,
 177          * now that we're doing dynamic initialization here, that we preserve
 178          * the old semantics: if an application modifies one of these three
 179          * fields of _res before res_init() is called, res_init() will not
 180          * alter them.  Of course, if an application is setting them to
 181          * _zero_ before calling res_init(), hoping to override what used
 182          * to be the static default, we can't detect it and unexpected results
 183          * will follow.  Zero for any of these fields would make no sense,
 184          * so one can safely assume that the applications were already getting
 185          * unexpected results.
 186          *
 187          * _res.options is tricky since some apps were known to diddle the bits
 188          * before res_init() was first called. We can't replicate that semantic
 189          * with dynamic initialization (they may have turned bits off that are
 190          * set in RES_DEFAULT).  Our solution is to declare such applications
 191          * "broken".  They could fool us by setting RES_INIT but none do (yet).
 192          */
 193         if (!_res.retrans)
 194                 _res.retrans = RES_TIMEOUT;
 195         if (!_res.retry)
 196                 _res.retry = 4;
 197         if (!(_res.options & RES_INIT))
 198                 _res.options = RES_DEFAULT;
 199
 200         /*
 201          * This one used to initialize implicitly to zero, so unless the app
 202          * has set it to something in particular, we can randomize it now.
 203          */
 204         if (!_res.id)
 205                 _res.id = res_randomid();
 206
 207 #ifdef USELOOPBACK
 208         _res.nsaddr.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
 209 #else
 210         _res.nsaddr.sin_addr.s_addr = INADDR_ANY;
 211 #endif
 212         _res.nsaddr.sin_family = AF_INET;
 213         _res.nsaddr.sin_port = htons(NAMESERVER_PORT);
 214         _res.nscount = 1;
 215         _res.ndots = 1;
 216         _res.pfcode = 0;
 217
 218         /* Allow user to override the local domain definition */
 219         if ((cp = __secure_getenv("LOCALDOMAIN")) != NULL) {
 220                 (void)strncpy(_res.defdname, cp, sizeof(_res.defdname) - 1);
 221                 haveenv++;
 222
 223                 /*
 224                  * Set search list to be blank-separated strings
 225                  * from rest of env value.  Permits users of LOCALDOMAIN
 226                  * to still have a search list, and anyone to set the
 227                  * one that they want to use as an individual (even more
 228                  * important now that the rfc1535 stuff restricts searches)
 229                  */
 230                 cp = _res.defdname;
 231                 pp = _res.dnsrch;
 232                 *pp++ = cp;
 233                 for (n = 0; *cp && pp < _res.dnsrch + MAXDNSRCH; cp++) {
 234                         if (*cp == '\n')        /* silly backwards compat */
 235                                 break;
 236                         else if (*cp == ' ' || *cp == '\t') {
 237                                 *cp = 0;
 238                                 n = 1;
 239                         } else if (n) {
 240                                 *pp++ = cp;
 241                                 n = 0;
 242                                 havesearch = 1;
 243                         }
 244                 }
 245                 /* null terminate last domain if there are excess */
 246                 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
 247                         cp++;
 248                 *cp = '\0';
 249                 *pp++ = 0;
 250         }
 251
 252 #define MATCH(line, name) \
 253         (!strncmp(line, name, sizeof(name) - 1) && \
 254         (line[sizeof(name) - 1] == ' ' || \
 255          line[sizeof(name) - 1] == '\t'))
 256
 257 #ifdef  NeXT
 258         if (netinfo_res_init(&haveenv, &havesearch) == 0)
 259 #endif
 260         if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
 261             /* read the config file */
 262             while (fgets(buf, sizeof(buf), fp) != NULL) {
 263                 /* skip comments */
 264                 if (*buf == ';' || *buf == '#')
 265                         continue;
 266                 /* read default domain name */
 267                 if (MATCH(buf, "domain")) {
 268                     if (haveenv)        /* skip if have from environ */
 269                             continue;
 270                     cp = buf + sizeof("domain") - 1;
 271                     while (*cp == ' ' || *cp == '\t')
 272                             cp++;
 273                     if ((*cp == '\0') || (*cp == '\n'))
 274                             continue;
 275                     strncpy(_res.defdname, cp, sizeof(_res.defdname) - 1);
 276                     if ((cp = strpbrk(_res.defdname, " \t\n")) != NULL)
 277                             *cp = '\0';
 278                     havesearch = 0;
 279                     continue;
 280                 }
 281                 /* set search list */
 282                 if (MATCH(buf, "search")) {
 283                     if (haveenv)        /* skip if have from environ */
 284                             continue;
 285                     cp = buf + sizeof("search") - 1;
 286                     while (*cp == ' ' || *cp == '\t')
 287                             cp++;
 288                     if ((*cp == '\0') || (*cp == '\n'))
 289                             continue;
 290                     strncpy(_res.defdname, cp, sizeof(_res.defdname) - 1);
 291                     if ((cp = strchr(_res.defdname, '\n')) != NULL)
 292                             *cp = '\0';
 293                     /*
 294                      * Set search list to be blank-separated strings
 295                      * on rest of line.
 296                      */
 297                     cp = _res.defdname;
 298                     pp = _res.dnsrch;
 299                     *pp++ = cp;
 300                     for (n = 0; *cp && pp < _res.dnsrch + MAXDNSRCH; cp++) {
 301                             if (*cp == ' ' || *cp == '\t') {
 302                                     *cp = 0;
 303                                     n = 1;
 304                             } else if (n) {
 305                                     *pp++ = cp;
 306                                     n = 0;
 307                             }
 308                     }
 309                     /* null terminate last domain if there are excess */
 310                     while (*cp != '\0' && *cp != ' ' && *cp != '\t')
 311                             cp++;
 312                     *cp = '\0';
 313                     *pp++ = 0;
 314                     havesearch = 1;
 315                     continue;
 316                 }
 317                 /* read nameservers to query */
 318                 if (MATCH(buf, "nameserver") && nserv < MAXNS) {
 319                     struct in_addr a;
 320
 321                     cp = buf + sizeof("nameserver") - 1;
 322                     while (*cp == ' ' || *cp == '\t')
 323                         cp++;
 324                     if ((*cp != '\0') && (*cp != '\n') && inet_aton(cp, &a)) {
 325                         _res.nsaddr_list[nserv].sin_addr = a;
 326                         _res.nsaddr_list[nserv].sin_family = AF_INET;
 327                         _res.nsaddr_list[nserv].sin_port =
 328                                 htons(NAMESERVER_PORT);
 329                         nserv++;
 330                     }
 331                     continue;
 332                 }
 333 #ifdef RESOLVSORT
 334                 if (MATCH(buf, "sortlist")) {
 335                     struct in_addr a;
 336
 337                     cp = buf + sizeof("sortlist") - 1;
 338                     while (nsort < MAXRESOLVSORT) {
 339                         while (*cp == ' ' || *cp == '\t')
 340                             cp++;
 341                         if (*cp == '\0' || *cp == '\n' || *cp == ';')
 342                             break;
 343                         net = cp;
 344                         while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
 345                                isascii(*cp) && !isspace(*cp))
 346                                 cp++;
 347                         n = *cp;
 348                         *cp = 0;
 349                         if (inet_aton(net, &a)) {
 350                             _res.sort_list[nsort].addr = a;
 351                             if (ISSORTMASK(n)) {
 352                                 *cp++ = n;
 353                                 net = cp;
 354                                 while (*cp && *cp != ';' &&
 355                                         isascii(*cp) && !isspace(*cp))
 356                                     cp++;
 357                                 n = *cp;
 358                                 *cp = 0;
 359                                 if (inet_aton(net, &a)) {
 360                                     _res.sort_list[nsort].mask = a.s_addr;
 361                                 } else {
 362                                     _res.sort_list[nsort].mask =
 363                                         net_mask(_res.sort_list[nsort].addr);
 364                                 }
 365                             } else {
 366                                 _res.sort_list[nsort].mask =
 367                                     net_mask(_res.sort_list[nsort].addr);
 368                             }
 369                             nsort++;
 370                         }
 371                         *cp = n;
 372                     }
 373                     continue;
 374                 }
 375 #endif
 376                 if (MATCH(buf, "options")) {
 377                     res_setoptions(buf + sizeof("options") - 1, "conf");
 378                     continue;
 379                 }
 380             }
 381             if (nserv > 1)
 382                 _res.nscount = nserv;
 383 #ifdef RESOLVSORT
 384             _res.nsort = nsort;
 385 #endif
 386             (void) fclose(fp);
 387         }
 388         if (_res.defdname[0] == 0 &&
 389             gethostname(buf, sizeof(_res.defdname) - 1) == 0 &&
 390             (cp = strchr(buf, '.')) != NULL)
 391                 strcpy(_res.defdname, cp + 1);
 392
 393         /* find components of local domain that might be searched */
 394         if (havesearch == 0) {
 395                 pp = _res.dnsrch;
 396                 *pp++ = _res.defdname;
 397                 *pp = NULL;
 398
 399 #ifndef RFC1535
 400                 dots = 0;
 401                 for (cp = _res.defdname; *cp; cp++)
 402                         dots += (*cp == '.');
 403
 404                 cp = _res.defdname;
 405                 while (pp < _res.dnsrch + MAXDFLSRCH) {
 406                         if (dots < LOCALDOMAINPARTS)
 407                                 break;
 408                         cp = strchr(cp, '.') + 1;    /* we know there is one */
 409                         *pp++ = cp;
 410                         dots--;
 411                 }
 412                 *pp = NULL;
 413 #ifdef DEBUG
 414                 if (_res.options & RES_DEBUG) {
 415                         printf(";; res_init()... default dnsrch list:\n");
 416                         for (pp = _res.dnsrch; *pp; pp++)
 417                                 printf(";;\t%s\n", *pp);
 418                         printf(";;\t..END..\n");
 419                 }
 420 #endif /* DEBUG */
 421 #endif /* !RFC1535 */
 422         }
 423
 424         if ((cp = __secure_getenv("RES_OPTIONS")) != NULL)
 425                 res_setoptions(cp, "env");
 426         _res.options |= RES_INIT;
 427         return (0);
 428 }
 429
 430 static void
 431 res_setoptions(options, source)
 432         char *options, *source;
 433 {
 434         char *cp = options;
 435         int i;
 436
 437 #ifdef DEBUG
 438         if (_res.options & RES_DEBUG)
 439                 printf(";; res_setoptions(\"%s\", \"%s\")...\n",
 440                        options, source);
 441 #endif
 442         while (*cp) {
 443                 /* skip leading and inner runs of spaces */
 444                 while (*cp == ' ' || *cp == '\t')
 445                         cp++;
 446                 /* search for and process individual options */
 447                 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
 448                         i = atoi(cp + sizeof("ndots:") - 1);
 449                         if (i <= RES_MAXNDOTS)
 450                                 _res.ndots = i;
 451                         else
 452                                 _res.ndots = RES_MAXNDOTS;
 453 #ifdef DEBUG
 454                         if (_res.options & RES_DEBUG)
 455                                 printf(";;\tndots=%d\n", _res.ndots);
 456 #endif
 457                 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
 458 #ifdef DEBUG
 459                         if (!(_res.options & RES_DEBUG)) {
 460                                 printf(";; res_setoptions(\"%s\", \"%s\")..\n",
 461                                        options, source);
 462                                 _res.options |= RES_DEBUG;
 463                         }
 464                         printf(";;\tdebug\n");
 465 #endif
 466                 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
 467                         _res.options |= RES_USE_INET6;
 468                 } else {
 469                         /* XXX - print a warning here? */
 470                 }
 471                 /* skip to next run of spaces */
 472                 while (*cp && *cp != ' ' && *cp != '\t')
 473                         cp++;
 474         }
 475 }
 476
 477 #ifdef RESOLVSORT
 478 /* XXX - should really support CIDR which means explicit masks always. */
 479 static u_int32_t
 480 net_mask(in)            /* XXX - should really use system's version of this */
 481         struct in_addr in;
 482 {
 483         register u_int32_t i = ntohl(in.s_addr);
 484
 485         if (IN_CLASSA(i))
 486                 return (htonl(IN_CLASSA_NET));
 487         else if (IN_CLASSB(i))
 488                 return (htonl(IN_CLASSB_NET));
 489         return (htonl(IN_CLASSC_NET));
 490 }
 491 #endif
 492
 493 #ifdef  NeXT
 494 static int
 495 netinfo_res_init(haveenv, havesearch)
 496         int *haveenv;
 497         int *havesearch;
 498 {
 499     register    int n;
 500     void        *domain, *parent;
 501     ni_id       dir;
 502     ni_status   status;
 503     ni_namelist nl;
 504     int         nserv = 0;
 505 #ifdef RESOLVSORT
 506     int         nsort = 0;
 507 #endif
 508
 509     status = ni_open(NULL, ".", &domain);
 510     if (status == NI_OK) {
 511         ni_setreadtimeout(domain, NI_TIMEOUT);
 512         ni_setabort(domain, 1);
 513
 514         /* climb the NetInfo hierarchy to find a resolver directory */
 515         while (status == NI_OK) {
 516             status = ni_pathsearch(domain, &dir, NI_PATH_RESCONF);
 517             if (status == NI_OK) {
 518             /* found a resolver directory */
 519
 520                 if (*haveenv == 0) {
 521                     /* get the default domain name */
 522                     status = ni_lookupprop(domain, &dir, "domain", &nl);
 523                     if (status == NI_OK && nl.ni_namelist_len > 0) {
 524                         (void)strncpy(_res.defdname,
 525                                       nl.ni_namelist_val[0],
 526                                       sizeof(_res.defdname) - 1);
 527                         _res.defdname[sizeof(_res.defdname) - 1] = '\0';
 528                         ni_namelist_free(&nl);
 529                         *havesearch = 0;
 530                     }
 531
 532                     /* get search list */
 533                     status = ni_lookupprop(domain, &dir, "search", &nl);
 534                     if (status == NI_OK && nl.ni_namelist_len > 0) {
 535                         (void)strncpy(_res.defdname,
 536                                       nl.ni_namelist_val[0],
 537                                       sizeof(_res.defdname) - 1);
 538                         _res.defdname[sizeof(_res.defdname) - 1] = '\0';
 539                         /* copy  */
 540                         for (n = 0;
 541                              n < nl.ni_namelist_len && n < MAXDNSRCH;
 542                              n++) {
 543                              /* duplicate up to MAXDNSRCH servers */
 544                              char *cp = nl.ni_namelist_val[n];
 545                             _res.dnsrch[n] =
 546                                 strcpy((char *)malloc(strlen(cp) + 1), cp);
 547                         }
 548                         ni_namelist_free(&nl);
 549                         *havesearch = 1;
 550                     }
 551                 }
 552
 553                 /* get list of nameservers */
 554                 status = ni_lookupprop(domain, &dir, "nameserver", &nl);
 555                 if (status == NI_OK && nl.ni_namelist_len > 0) {
 556                     /* copy up to MAXNS servers */
 557                     for (n = 0;
 558                          n < nl.ni_namelist_len && nserv < MAXNS;
 559                          n++) {
 560                         struct in_addr a;
 561
 562                         if (inet_aton(nl.ni_namelist_val[n], &a)) {
 563                             _res.nsaddr_list[nserv].sin_addr = a;
 564                             _res.nsaddr_list[nserv].sin_family = AF_INET;
 565                             _res.nsaddr_list[nserv].sin_port =
 566                                 htons(NAMESERVER_PORT);
 567                             nserv++;
 568                         }
 569                     }
 570                     ni_namelist_free(&nl);
 571                 }
 572
 573                 if (nserv > 1)
 574                     _res.nscount = nserv;
 575
 576 #ifdef RESOLVSORT
 577                 /* get sort order */
 578                 status = ni_lookupprop(domain, &dir, "sortlist", &nl);
 579                 if (status == NI_OK && nl.ni_namelist_len > 0) {
 580
 581                     /* copy up to MAXRESOLVSORT address/netmask pairs */
 582                     for (n = 0;
 583                          n < nl.ni_namelist_len && nsort < MAXRESOLVSORT;
 584                          n++) {
 585                         char ch;
 586                         char *cp;
 587                         const char *sp;
 588                         struct in_addr a;
 589
 590                         cp = NULL;
 591                         for (sp = sort_mask; *sp; sp++) {
 592                                 char *cp1;
 593                                 cp1 = strchr(nl.ni_namelist_val[n], *sp);
 594                                 if (cp && cp1)
 595                                         cp = (cp < cp1)? cp : cp1;
 596                                 else if (cp1)
 597                                         cp = cp1;
 598                         }
 599                         if (cp != NULL) {
 600                                 ch = *cp;
 601                                 *cp = '\0';
 602                                 break;
 603                         }
 604                         if (inet_aton(nl.ni_namelist_val[n], &a)) {
 605                             _res.sort_list[nsort].addr = a;
 606                             if (*cp && ISSORTMASK(ch)) {
 607                                 *cp++ = ch;
 608                                 if (inet_aton(cp, &a)) {
 609                                     _res.sort_list[nsort].mask = a.s_addr;
 610                                 } else {
 611                                     _res.sort_list[nsort].mask =
 612                                         net_mask(_res.sort_list[nsort].addr);
 613                                 }
 614                             } else {
 615                                 _res.sort_list[nsort].mask =
 616                                     net_mask(_res.sort_list[nsort].addr);
 617                             }
 618                             nsort++;
 619                         }
 620                     }
 621                     ni_namelist_free(&nl);
 622                 }
 623
 624                 _res.nsort = nsort;
 625 #endif
 626
 627                 /* get resolver options */
 628                 status = ni_lookupprop(domain, &dir, "options", &nl);
 629                 if (status == NI_OK && nl.ni_namelist_len > 0) {
 630                     res_setoptions(nl.ni_namelist_val[0], "conf");
 631                     ni_namelist_free(&nl);
 632                 }
 633
 634                 ni_free(domain);
 635                 return(1);      /* using DNS configuration from NetInfo */
 636             }
 637
 638             status = ni_open(domain, "..", &parent);
 639             ni_free(domain);
 640             if (status == NI_OK)
 641                 domain = parent;
 642         }
 643     }
 644     return(0);  /* if not using DNS configuration from NetInfo */
 645 }
 646 #endif  /* NeXT */
 647
 648 u_int
 649 res_randomid()
 650 {
 651         struct timeval now;
 652
 653         gettimeofday(&now, NULL);
 654         return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid()));
 655 }