contrib/bind-9.2.4rc7/lib/bind/resolv/res_init.c

   1 /*
   2  * Copyright (c) 1985, 1989, 1993
   3  *    The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. 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
  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
  54 /*
  55  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
  56  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
  57  *
  58  * Permission to use, copy, modify, and distribute this software for any
  59  * purpose with or without fee is hereby granted, provided that the above
  60  * copyright notice and this permission notice appear in all copies.
  61  *
  62  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
  63  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  64  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  65  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  66  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  67  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  68  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  69  */
  70
  71 #if defined(LIBC_SCCS) && !defined(lint)
  72 static const char sccsid[] = "@(#)res_init.c    8.1 (Berkeley) 6/7/93";
  73 static const char rcsid[] = "$Id: res_init.c,v 1.9.2.7 2004/03/16 12:35:35 marka Exp $";
  74 #endif /* LIBC_SCCS and not lint */
  75
  76 #include "port_before.h"
  77
  78 #include <sys/types.h>
  79 #include <sys/param.h>
  80 #include <sys/socket.h>
  81 #include <sys/time.h>
  82
  83 #include <netinet/in.h>
  84 #include <arpa/inet.h>
  85 #include <arpa/nameser.h>
  86
  87 #include <ctype.h>
  88 #include <stdio.h>
  89 #include <stdlib.h>
  90 #include <string.h>
  91 #include <unistd.h>
  92 #include <netdb.h>
  93
  94 #include "port_after.h"
  95
  96 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
  97 #include <resolv.h>
  98
  99 #include "res_private.h"
 100
 101 /* Options.  Should all be left alone. */
 102 #define RESOLVSORT
 103 #define DEBUG
 104
 105 static void res_setoptions __P((res_state, const char *, const char *));
 106
 107 #ifdef RESOLVSORT
 108 static const char sort_mask[] = "/&";
 109 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
 110 static u_int32_t net_mask __P((struct in_addr));
 111 #endif
 112
 113 #if !defined(isascii)   /* XXX - could be a function */
 114 # define isascii(c) (!(c & 0200))
 115 #endif
 116
 117 /*
 118  * Resolver state default settings.
 119  */
 120
 121 /*
 122  * Set up default settings.  If the configuration file exist, the values
 123  * there will have precedence.  Otherwise, the server address is set to
 124  * INADDR_ANY and the default domain name comes from the gethostname().
 125  *
 126  * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
 127  * rather than INADDR_ANY ("0.0.0.0") as the default name server address
 128  * since it was noted that INADDR_ANY actually meant ``the first interface
 129  * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
 130  * it had to be "up" in order for you to reach your own name server.  It
 131  * was later decided that since the recommended practice is to always
 132  * install local static routes through 127.0.0.1 for all your network
 133  * interfaces, that we could solve this problem without a code change.
 134  *
 135  * The configuration file should always be used, since it is the only way
 136  * to specify a default domain.  If you are running a server on your local
 137  * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
 138  * in the configuration file.
 139  *
 140  * Return 0 if completes successfully, -1 on error
 141  */
 142 int
 143 res_ninit(res_state statp) {
 144         extern int __res_vinit(res_state, int);
 145
 146         return (__res_vinit(statp, 0));
 147 }
 148
 149 /* This function has to be reachable by res_data.c but not publically. */
 150 int
 151 __res_vinit(res_state statp, int preinit) {
 152         register FILE *fp;
 153         register char *cp, **pp;
 154         register int n;
 155         char buf[BUFSIZ];
 156         int nserv = 0;    /* number of nameserver records read from file */
 157         int haveenv = 0;
 158         int havesearch = 0;
 159 #ifdef RESOLVSORT
 160         int nsort = 0;
 161         char *net;
 162 #endif
 163         int dots;
 164         union res_sockaddr_union u[2];
 165
 166         if (!preinit) {
 167                 statp->retrans = RES_TIMEOUT;
 168                 statp->retry = RES_DFLRETRY;
 169                 statp->options = RES_DEFAULT;
 170                 statp->id = res_randomid();
 171         }
 172
 173         if ((statp->options & RES_INIT) != 0U)
 174                 res_ndestroy(statp);
 175
 176         memset(u, 0, sizeof(u));
 177 #ifdef USELOOPBACK
 178         u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
 179 #else
 180         u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
 181 #endif
 182         u[nserv].sin.sin_family = AF_INET;
 183         u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
 184 #ifdef HAVE_SA_LEN
 185         u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
 186 #endif
 187         nserv++;
 188 #ifdef HAS_INET6_STRUCTS
 189 #ifdef USELOOPBACK
 190         u[nserv].sin6.sin6_addr = in6addr_loopback;
 191 #else
 192         u[nserv].sin6.sin6_addr = in6addr_any;
 193 #endif
 194         u[nserv].sin6.sin6_family = AF_INET6;
 195         u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
 196 #ifdef HAVE_SA_LEN
 197         u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
 198 #endif
 199         nserv++;
 200 #endif
 201         statp->nscount = 0;
 202         statp->ndots = 1;
 203         statp->pfcode = 0;
 204         statp->_vcsock = -1;
 205         statp->_flags = 0;
 206         statp->qhook = NULL;
 207         statp->rhook = NULL;
 208         statp->_u._ext.nscount = 0;
 209         statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
 210         if (statp->_u._ext.ext != NULL) {
 211                 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
 212                 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
 213                 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
 214                 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
 215         }
 216 #ifdef RESOLVSORT
 217         statp->nsort = 0;
 218 #endif
 219         res_setservers(statp, u, nserv);
 220
 221         /* Allow user to override the local domain definition */
 222         if ((cp = getenv("LOCALDOMAIN")) != NULL) {
 223                 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
 224                 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 225                 haveenv++;
 226
 227                 /*
 228                  * Set search list to be blank-separated strings
 229                  * from rest of env value.  Permits users of LOCALDOMAIN
 230                  * to still have a search list, and anyone to set the
 231                  * one that they want to use as an individual (even more
 232                  * important now that the rfc1535 stuff restricts searches)
 233                  */
 234                 cp = statp->defdname;
 235                 pp = statp->dnsrch;
 236                 *pp++ = cp;
 237                 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
 238                         if (*cp == '\n')        /* silly backwards compat */
 239                                 break;
 240                         else if (*cp == ' ' || *cp == '\t') {
 241                                 *cp = 0;
 242                                 n = 1;
 243                         } else if (n) {
 244                                 *pp++ = cp;
 245                                 n = 0;
 246                                 havesearch = 1;
 247                         }
 248                 }
 249                 /* null terminate last domain if there are excess */
 250                 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
 251                         cp++;
 252                 *cp = '\0';
 253                 *pp++ = 0;
 254         }
 255
 256 #define MATCH(line, name) \
 257         (!strncmp(line, name, sizeof(name) - 1) && \
 258         (line[sizeof(name) - 1] == ' ' || \
 259          line[sizeof(name) - 1] == '\t'))
 260
 261         nserv = 0;
 262         if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
 263             /* read the config file */
 264             while (fgets(buf, sizeof(buf), fp) != NULL) {
 265                 /* skip comments */
 266                 if (*buf == ';' || *buf == '#')
 267                         continue;
 268                 /* read default domain name */
 269                 if (MATCH(buf, "domain")) {
 270                     if (haveenv)        /* skip if have from environ */
 271                             continue;
 272                     cp = buf + sizeof("domain") - 1;
 273                     while (*cp == ' ' || *cp == '\t')
 274                             cp++;
 275                     if ((*cp == '\0') || (*cp == '\n'))
 276                             continue;
 277                     strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
 278                     statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 279                     if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
 280                             *cp = '\0';
 281                     havesearch = 0;
 282                     continue;
 283                 }
 284                 /* set search list */
 285                 if (MATCH(buf, "search")) {
 286                     if (haveenv)        /* skip if have from environ */
 287                             continue;
 288                     cp = buf + sizeof("search") - 1;
 289                     while (*cp == ' ' || *cp == '\t')
 290                             cp++;
 291                     if ((*cp == '\0') || (*cp == '\n'))
 292                             continue;
 293                     strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
 294                     statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 295                     if ((cp = strchr(statp->defdname, '\n')) != NULL)
 296                             *cp = '\0';
 297                     /*
 298                      * Set search list to be blank-separated strings
 299                      * on rest of line.
 300                      */
 301                     cp = statp->defdname;
 302                     pp = statp->dnsrch;
 303                     *pp++ = cp;
 304                     for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
 305                             if (*cp == ' ' || *cp == '\t') {
 306                                     *cp = 0;
 307                                     n = 1;
 308                             } else if (n) {
 309                                     *pp++ = cp;
 310                                     n = 0;
 311                             }
 312                     }
 313                     /* null terminate last domain if there are excess */
 314                     while (*cp != '\0' && *cp != ' ' && *cp != '\t')
 315                             cp++;
 316                     *cp = '\0';
 317                     *pp++ = 0;
 318                     havesearch = 1;
 319                     continue;
 320                 }
 321                 /* read nameservers to query */
 322                 if (MATCH(buf, "nameserver") && nserv < MAXNS) {
 323                     struct addrinfo hints, *ai;
 324                     char sbuf[NI_MAXSERV];
 325                     const size_t minsiz =
 326                         sizeof(statp->_u._ext.ext->nsaddrs[0]);
 327
 328                     cp = buf + sizeof("nameserver") - 1;
 329                     while (*cp == ' ' || *cp == '\t')
 330                         cp++;
 331                     cp[strcspn(cp, ";# \t\n")] = '\0';
 332                     if ((*cp != '\0') && (*cp != '\n')) {
 333                         memset(&hints, 0, sizeof(hints));
 334                         hints.ai_family = PF_UNSPEC;
 335                         hints.ai_socktype = SOCK_DGRAM; /*dummy*/
 336                         hints.ai_flags = AI_NUMERICHOST;
 337                         sprintf(sbuf, "%u", NAMESERVER_PORT);
 338                         if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
 339                             ai->ai_addrlen <= minsiz) {
 340                             if (statp->_u._ext.ext != NULL) {
 341                                 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 342                                     ai->ai_addr, ai->ai_addrlen);
 343                             }
 344                             if (ai->ai_addrlen <=
 345                                 sizeof(statp->nsaddr_list[nserv])) {
 346                                 memcpy(&statp->nsaddr_list[nserv],
 347                                     ai->ai_addr, ai->ai_addrlen);
 348                             } else
 349                                 statp->nsaddr_list[nserv].sin_family = 0;
 350                             freeaddrinfo(ai);
 351                             nserv++;
 352                         }
 353                     }
 354                     continue;
 355                 }
 356 #ifdef RESOLVSORT
 357                 if (MATCH(buf, "sortlist")) {
 358                     struct in_addr a;
 359
 360                     cp = buf + sizeof("sortlist") - 1;
 361                     while (nsort < MAXRESOLVSORT) {
 362                         while (*cp == ' ' || *cp == '\t')
 363                             cp++;
 364                         if (*cp == '\0' || *cp == '\n' || *cp == ';')
 365                             break;
 366                         net = cp;
 367                         while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
 368                                isascii(*cp) && !isspace((unsigned char)*cp))
 369                                 cp++;
 370                         n = *cp;
 371                         *cp = 0;
 372                         if (inet_aton(net, &a)) {
 373                             statp->sort_list[nsort].addr = a;
 374                             if (ISSORTMASK(n)) {
 375                                 *cp++ = n;
 376                                 net = cp;
 377                                 while (*cp && *cp != ';' &&
 378                                         isascii(*cp) &&
 379                                         !isspace((unsigned char)*cp))
 380                                     cp++;
 381                                 n = *cp;
 382                                 *cp = 0;
 383                                 if (inet_aton(net, &a)) {
 384                                     statp->sort_list[nsort].mask = a.s_addr;
 385                                 } else {
 386                                     statp->sort_list[nsort].mask =
 387                                         net_mask(statp->sort_list[nsort].addr);
 388                                 }
 389                             } else {
 390                                 statp->sort_list[nsort].mask =
 391                                     net_mask(statp->sort_list[nsort].addr);
 392                             }
 393                             nsort++;
 394                         }
 395                         *cp = n;
 396                     }
 397                     continue;
 398                 }
 399 #endif
 400                 if (MATCH(buf, "options")) {
 401                     res_setoptions(statp, buf + sizeof("options") - 1, "conf");
 402                     continue;
 403                 }
 404             }
 405             if (nserv > 0)
 406                 statp->nscount = nserv;
 407 #ifdef RESOLVSORT
 408             statp->nsort = nsort;
 409 #endif
 410             (void) fclose(fp);
 411         }
 412 /*
 413  * Last chance to get a nameserver.  This should not normally
 414  * be necessary
 415  */
 416 #ifdef NO_RESOLV_CONF
 417         if(nserv == 0)
 418                 nserv = get_nameservers(statp);
 419 #endif
 420
 421         if (statp->defdname[0] == 0 &&
 422             gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
 423             (cp = strchr(buf, '.')) != NULL)
 424                 strcpy(statp->defdname, cp + 1);
 425
 426         /* find components of local domain that might be searched */
 427         if (havesearch == 0) {
 428                 pp = statp->dnsrch;
 429                 *pp++ = statp->defdname;
 430                 *pp = NULL;
 431
 432                 dots = 0;
 433                 for (cp = statp->defdname; *cp; cp++)
 434                         dots += (*cp == '.');
 435
 436                 cp = statp->defdname;
 437                 while (pp < statp->dnsrch + MAXDFLSRCH) {
 438                         if (dots < LOCALDOMAINPARTS)
 439                                 break;
 440                         cp = strchr(cp, '.') + 1;    /* we know there is one */
 441                         *pp++ = cp;
 442                         dots--;
 443                 }
 444                 *pp = NULL;
 445 #ifdef DEBUG
 446                 if (statp->options & RES_DEBUG) {
 447                         printf(";; res_init()... default dnsrch list:\n");
 448                         for (pp = statp->dnsrch; *pp; pp++)
 449                                 printf(";;\t%s\n", *pp);
 450                         printf(";;\t..END..\n");
 451                 }
 452 #endif
 453         }
 454
 455         if ((cp = getenv("RES_OPTIONS")) != NULL)
 456                 res_setoptions(statp, cp, "env");
 457         statp->options |= RES_INIT;
 458         return (0);
 459 }
 460
 461 static void
 462 res_setoptions(res_state statp, const char *options, const char *source)
 463 {
 464         const char *cp = options;
 465         int i;
 466         struct __res_state_ext *ext = statp->_u._ext.ext;
 467
 468 #ifdef DEBUG
 469         if (statp->options & RES_DEBUG)
 470                 printf(";; res_setoptions(\"%s\", \"%s\")...\n",
 471                        options, source);
 472 #endif
 473         while (*cp) {
 474                 /* skip leading and inner runs of spaces */
 475                 while (*cp == ' ' || *cp == '\t')
 476                         cp++;
 477                 /* search for and process individual options */
 478                 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
 479                         i = atoi(cp + sizeof("ndots:") - 1);
 480                         if (i <= RES_MAXNDOTS)
 481                                 statp->ndots = i;
 482                         else
 483                                 statp->ndots = RES_MAXNDOTS;
 484 #ifdef DEBUG
 485                         if (statp->options & RES_DEBUG)
 486                                 printf(";;\tndots=%d\n", statp->ndots);
 487 #endif
 488                 } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
 489                         i = atoi(cp + sizeof("timeout:") - 1);
 490                         if (i <= RES_MAXRETRANS)
 491                                 statp->retrans = i;
 492                         else
 493                                 statp->retrans = RES_MAXRETRANS;
 494 #ifdef DEBUG
 495                         if (statp->options & RES_DEBUG)
 496                                 printf(";;\ttimeout=%d\n", statp->retrans);
 497 #endif
 498                 } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
 499                         i = atoi(cp + sizeof("attempts:") - 1);
 500                         if (i <= RES_MAXRETRY)
 501                                 statp->retry = i;
 502                         else
 503                                 statp->retry = RES_MAXRETRY;
 504 #ifdef DEBUG
 505                         if (statp->options & RES_DEBUG)
 506                                 printf(";;\tattempts=%d\n", statp->retry);
 507 #endif
 508                 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
 509 #ifdef DEBUG
 510                         if (!(statp->options & RES_DEBUG)) {
 511                                 printf(";; res_setoptions(\"%s\", \"%s\")..\n",
 512                                        options, source);
 513                                 statp->options |= RES_DEBUG;
 514                         }
 515                         printf(";;\tdebug\n");
 516 #endif
 517                 } else if (!strncmp(cp, "no_tld_query",
 518                                     sizeof("no_tld_query") - 1) ||
 519                            !strncmp(cp, "no-tld-query",
 520                                     sizeof("no-tld-query") - 1)) {
 521                         statp->options |= RES_NOTLDQUERY;
 522                 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
 523                         statp->options |= RES_USE_INET6;
 524                 } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
 525                         statp->options |= RES_ROTATE;
 526                 } else if (!strncmp(cp, "no-check-names",
 527                                     sizeof("no-check-names") - 1)) {
 528                         statp->options |= RES_NOCHECKNAME;
 529                 }
 530 #ifdef RES_USE_EDNS0
 531                 else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
 532                         statp->options |= RES_USE_EDNS0;
 533                 }
 534 #endif
 535                 else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
 536                         statp->options |= RES_USE_DNAME;
 537                 }
 538                 else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
 539                         if (ext == NULL)
 540                                 goto skip;
 541                         cp += sizeof("nibble:") - 1;
 542                         i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
 543                         strncpy(ext->nsuffix, cp, i);
 544                         ext->nsuffix[i] = '\0';
 545                 }
 546                 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
 547                         if (ext == NULL)
 548                                 goto skip;
 549                         cp += sizeof("nibble2:") - 1;
 550                         i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
 551                         strncpy(ext->nsuffix2, cp, i);
 552                         ext->nsuffix2[i] = '\0';
 553                 }
 554                 else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
 555                         cp += sizeof("v6revmode:") - 1;
 556                         /* "nibble" and "bitstring" used to be valid */
 557                         if (!strncmp(cp, "single", sizeof("single") - 1)) {
 558                                 statp->options |= RES_NO_NIBBLE2;
 559                         } else if (!strncmp(cp, "both", sizeof("both") - 1)) {
 560                                 statp->options &=
 561                                          ~RES_NO_NIBBLE2;
 562                         }
 563                 }
 564                 else {
 565                         /* XXX - print a warning here? */
 566                 }
 567    skip:
 568                 /* skip to next run of spaces */
 569                 while (*cp && *cp != ' ' && *cp != '\t')
 570                         cp++;
 571         }
 572 }
 573
 574 #ifdef RESOLVSORT
 575 /* XXX - should really support CIDR which means explicit masks always. */
 576 static u_int32_t
 577 net_mask(in)            /* XXX - should really use system's version of this */
 578         struct in_addr in;
 579 {
 580         register u_int32_t i = ntohl(in.s_addr);
 581
 582         if (IN_CLASSA(i))
 583                 return (htonl(IN_CLASSA_NET));
 584         else if (IN_CLASSB(i))
 585                 return (htonl(IN_CLASSB_NET));
 586         return (htonl(IN_CLASSC_NET));
 587 }
 588 #endif
 589
 590 u_int
 591 res_randomid(void) {
 592         struct timeval now;
 593
 594         gettimeofday(&now, NULL);
 595         return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid()));
 596 }
 597
 598 /*
 599  * This routine is for closing the socket if a virtual circuit is used and
 600  * the program wants to close it.  This provides support for endhostent()
 601  * which expects to close the socket.
 602  *
 603  * This routine is not expected to be user visible.
 604  */
 605 void
 606 res_nclose(res_state statp) {
 607         int ns;
 608
 609         if (statp->_vcsock >= 0) {
 610                 (void) close(statp->_vcsock);
 611                 statp->_vcsock = -1;
 612                 statp->_flags &= ~(RES_F_VC | RES_F_CONN);
 613         }
 614         for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
 615                 if (statp->_u._ext.nssocks[ns] != -1) {
 616                         (void) close(statp->_u._ext.nssocks[ns]);
 617                         statp->_u._ext.nssocks[ns] = -1;
 618                 }
 619         }
 620 }
 621
 622 void
 623 res_ndestroy(res_state statp) {
 624         res_nclose(statp);
 625         if (statp->_u._ext.ext != NULL)
 626                 free(statp->_u._ext.ext);
 627         statp->options &= ~RES_INIT;
 628         statp->_u._ext.ext = NULL;
 629 }
 630
 631 const char *
 632 res_get_nibblesuffix(res_state statp) {
 633         if (statp->_u._ext.ext)
 634                 return (statp->_u._ext.ext->nsuffix);
 635         return ("ip6.arpa");
 636 }
 637
 638 const char *
 639 res_get_nibblesuffix2(res_state statp) {
 640         if (statp->_u._ext.ext)
 641                 return (statp->_u._ext.ext->nsuffix2);
 642         return ("ip6.int");
 643 }
 644
 645 void
 646 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {
 647         int i, nserv;
 648         size_t size;
 649
 650         /* close open servers */
 651         res_nclose(statp);
 652
 653         /* cause rtt times to be forgotten */
 654         statp->_u._ext.nscount = 0;
 655
 656         nserv = 0;
 657         for (i = 0; i < cnt && nserv < MAXNS; i++) {
 658                 switch (set->sin.sin_family) {
 659                 case AF_INET:
 660                         size = sizeof(set->sin);
 661                         if (statp->_u._ext.ext)
 662                                 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 663                                         &set->sin, size);
 664                         if (size <= sizeof(statp->nsaddr_list[nserv]))
 665                                 memcpy(&statp->nsaddr_list[nserv],
 666                                         &set->sin, size);
 667                         else
 668                                 statp->nsaddr_list[nserv].sin_family = 0;
 669                         nserv++;
 670                         break;
 671
 672 #ifdef HAS_INET6_STRUCTS
 673                 case AF_INET6:
 674                         size = sizeof(set->sin6);
 675                         if (statp->_u._ext.ext)
 676                                 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 677                                         &set->sin6, size);
 678                         if (size <= sizeof(statp->nsaddr_list[nserv]))
 679                                 memcpy(&statp->nsaddr_list[nserv],
 680                                         &set->sin6, size);
 681                         else
 682                                 statp->nsaddr_list[nserv].sin_family = 0;
 683                         nserv++;
 684                         break;
 685 #endif
 686
 687                 default:
 688                         break;
 689                 }
 690                 set++;
 691         }
 692         statp->nscount = nserv;
 693
 694 }
 695
 696 int
 697 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {
 698         int i;
 699         size_t size;
 700         u_int16_t family;
 701
 702         for (i = 0; i < statp->nscount && i < cnt; i++) {
 703                 if (statp->_u._ext.ext)
 704                         family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
 705                 else
 706                         family = statp->nsaddr_list[i].sin_family;
 707
 708                 switch (family) {
 709                 case AF_INET:
 710                         size = sizeof(set->sin);
 711                         if (statp->_u._ext.ext)
 712                                 memcpy(&set->sin,
 713                                        &statp->_u._ext.ext->nsaddrs[i],
 714                                        size);
 715                         else
 716                                 memcpy(&set->sin, &statp->nsaddr_list[i],
 717                                        size);
 718                         break;
 719
 720 #ifdef HAS_INET6_STRUCTS
 721                 case AF_INET6:
 722                         size = sizeof(set->sin6);
 723                         if (statp->_u._ext.ext)
 724                                 memcpy(&set->sin6,
 725                                        &statp->_u._ext.ext->nsaddrs[i],
 726                                        size);
 727                         else
 728                                 memcpy(&set->sin6, &statp->nsaddr_list[i],
 729                                        size);
 730                         break;
 731 #endif
 732
 733                 default:
 734                         set->sin.sin_family = 0;
 735                         break;
 736                 }
 737                 set++;
 738         }
 739         return (statp->nscount);
 740 }