lib/libc/resolv/res_init.c

   1 /*      $NetBSD: res_init.c,v 1.21 2009/10/24 05:35:37 christos Exp $   */
   2
   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
  36 /*
  37  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
  38  *
  39  * Permission to use, copy, modify, and distribute this software for any
  40  * purpose with or without fee is hereby granted, provided that the above
  41  * copyright notice and this permission notice appear in all copies, and that
  42  * the name of Digital Equipment Corporation not be used in advertising or
  43  * publicity pertaining to distribution of the document or software without
  44  * specific, written prior permission.
  45  *
  46  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
  47  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
  48  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
  49  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  50  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  51  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  52  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  53  * SOFTWARE.
  54  */
  55
  56 /*
  57  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
  58  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
  59  *
  60  * Permission to use, copy, modify, and distribute this software for any
  61  * purpose with or without fee is hereby granted, provided that the above
  62  * copyright notice and this permission notice appear in all copies.
  63  *
  64  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
  65  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  66  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  67  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  68  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  69  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  70  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  71  */
  72
  73 #include <sys/cdefs.h>
  74 #if defined(LIBC_SCCS) && !defined(lint)
  75 #ifdef notdef
  76 static const char sccsid[] = "@(#)res_init.c    8.1 (Berkeley) 6/7/93";
  77 static const char rcsid[] = "Id: res_init.c,v 1.26 2008/12/11 09:59:00 marka Exp";
  78 #else
  79 __RCSID("$NetBSD: res_init.c,v 1.21 2009/10/24 05:35:37 christos Exp $");
  80 #endif
  81 #endif /* LIBC_SCCS and not lint */
  82
  83 #include "port_before.h"
  84
  85 #include "namespace.h"
  86 #include <sys/types.h>
  87 #include <sys/param.h>
  88 #include <sys/socket.h>
  89 #include <sys/stat.h>
  90 #include <sys/time.h>
  91 #include <sys/event.h>
  92
  93 #include <netinet/in.h>
  94 #include <arpa/inet.h>
  95 #include <arpa/nameser.h>
  96
  97 #include <ctype.h>
  98 #include <stdio.h>
  99 #include <stdlib.h>
 100 #include <string.h>
 101 #include <unistd.h>
 102 #include <fcntl.h>
 103 #include <netdb.h>
 104
 105 #define HAVE_MD5
 106 #include <md5.h>
 107
 108 #ifndef HAVE_MD5
 109 # include "../dst/md5.h"
 110 #else
 111 # ifdef SOLARIS2
 112 #  include <sys/md5.h>
 113 # endif
 114 #endif
 115 #ifndef _MD5_H_
 116 # define _MD5_H_ 1      /*%< make sure we do not include rsaref md5.h file */
 117 #endif
 118
 119 #include "port_after.h"
 120
 121 #if 0
 122 #ifdef __weak_alias
 123 __weak_alias(res_ninit,_res_ninit)
 124 __weak_alias(res_randomid,__res_randomid)
 125 __weak_alias(res_nclose,_res_nclose)
 126 __weak_alias(res_ndestroy,_res_ndestroy)
 127 __weak_alias(res_get_nibblesuffix,__res_get_nibblesuffix)
 128 __weak_alias(res_get_nibblesuffix2,__res_get_nibblesuffix2)
 129 __weak_alias(res_getservers,__res_getservers)
 130 __weak_alias(res_setservers,__res_setservers)
 131 #endif
 132 #endif
 133
 134
 135 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
 136 #include <resolv.h>
 137
 138 #include "res_private.h"
 139
 140 #define RESOLVSORT
 141 /*% Options.  Should all be left alone. */
 142 #ifndef DEBUG
 143 #define DEBUG
 144 #endif
 145
 146 #ifdef SOLARIS2
 147 #include <sys/systeminfo.h>
 148 #endif
 149
 150 static void res_setoptions __P((res_state, const char *, const char *));
 151
 152 #ifdef RESOLVSORT
 153 static const char sort_mask[] = "/&";
 154 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
 155 static u_int32_t net_mask __P((struct in_addr));
 156 #endif
 157
 158 #if !defined(isascii)   /*%< XXX - could be a function */
 159 # define isascii(c) (!(c & 0200))
 160 #endif
 161
 162 static struct timespec __res_conf_time;
 163 static const struct timespec ts = { 0, 0 };
 164
 165 /*
 166  * Resolver state default settings.
 167  */
 168
 169 /*%
 170  * Set up default settings.  If the configuration file exist, the values
 171  * there will have precedence.  Otherwise, the server address is set to
 172  * INADDR_ANY and the default domain name comes from the gethostname().
 173  *
 174  * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
 175  * rather than INADDR_ANY ("0.0.0.0") as the default name server address
 176  * since it was noted that INADDR_ANY actually meant ``the first interface
 177  * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
 178  * it had to be "up" in order for you to reach your own name server.  It
 179  * was later decided that since the recommended practice is to always
 180  * install local static routes through 127.0.0.1 for all your network
 181  * interfaces, that we could solve this problem without a code change.
 182  *
 183  * The configuration file should always be used, since it is the only way
 184  * to specify a default domain.  If you are running a server on your local
 185  * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
 186  * in the configuration file.
 187  *
 188  * Return 0 if completes successfully, -1 on error
 189  */
 190 int
 191 res_ninit(res_state statp) {
 192         return (__res_vinit(statp, 0));
 193 }
 194
 195 /*% This function has to be reachable by res_data.c but not publically. */
 196 int
 197 __res_vinit(res_state statp, int preinit) {
 198         register FILE *fp;
 199         register char *cp, **pp;
 200         register int n;
 201         char buf[BUFSIZ];
 202         int nserv = 0;    /*%< number of nameserver records read from file */
 203         int haveenv = 0;
 204         int havesearch = 0;
 205 #ifdef RESOLVSORT
 206         int nsort = 0;
 207         char *net;
 208 #endif
 209         int dots;
 210         union res_sockaddr_union u[2];
 211         int maxns = MAXNS;
 212
 213         RES_SET_H_ERRNO(statp, 0);
 214
 215         if ((statp->options & RES_INIT) != 0U)
 216                 res_ndestroy(statp);
 217
 218         if (!preinit) {
 219                 statp->retrans = RES_TIMEOUT;
 220                 statp->retry = RES_DFLRETRY;
 221                 statp->options = RES_DEFAULT;
 222         }
 223         statp->_rnd = malloc(16);
 224         res_rndinit(statp);
 225         statp->id = res_nrandomid(statp);
 226
 227         memset(u, 0, sizeof(u));
 228 #ifdef USELOOPBACK
 229         u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
 230 #else
 231         u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
 232 #endif
 233         u[nserv].sin.sin_family = AF_INET;
 234         u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
 235 #ifdef HAVE_SA_LEN
 236         u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
 237 #endif
 238         nserv++;
 239 #ifdef HAS_INET6_STRUCTS
 240 #ifdef USELOOPBACK
 241         u[nserv].sin6.sin6_addr = in6addr_loopback;
 242 #else
 243         u[nserv].sin6.sin6_addr = in6addr_any;
 244 #endif
 245         u[nserv].sin6.sin6_family = AF_INET6;
 246         u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
 247 #ifdef HAVE_SA_LEN
 248         u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
 249 #endif
 250         nserv++;
 251 #endif
 252         statp->nscount = 0;
 253         statp->ndots = 1;
 254         statp->pfcode = 0;
 255         statp->_vcsock = -1;
 256         statp->_flags = 0;
 257         statp->qhook = NULL;
 258         statp->rhook = NULL;
 259         statp->_u._ext.nscount = 0;
 260         statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
 261         if (statp->_u._ext.ext != NULL) {
 262                 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
 263                 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
 264                 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
 265                 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
 266         } else {
 267                 /*
 268                  * Historically res_init() rarely, if at all, failed.
 269                  * Examples and applications exist which do not check
 270                  * our return code.  Furthermore several applications
 271                  * simply call us to get the systems domainname.  So
 272                  * rather then immediately fail here we store the
 273                  * failure, which is returned later, in h_errno.  And
 274                  * prevent the collection of 'nameserver' information
 275                  * by setting maxns to 0.  Thus applications that fail
 276                  * to check our return code wont be able to make
 277                  * queries anyhow.
 278                  */
 279                 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
 280                 maxns = 0;
 281         }
 282 #ifdef RESOLVSORT
 283         statp->nsort = 0;
 284 #endif
 285         res_setservers(statp, u, nserv);
 286
 287 #ifdef  SOLARIS2
 288         /*
 289          * The old libresolv derived the defaultdomain from NIS/NIS+.
 290          * We want to keep this behaviour
 291          */
 292         {
 293                 char buf[sizeof(statp->defdname)], *cp;
 294                 int ret;
 295
 296                 if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 &&
 297                         (unsigned int)ret <= sizeof(buf)) {
 298                         if (buf[0] == '+')
 299                                 buf[0] = '.';
 300                         cp = strchr(buf, '.');
 301                         cp = (cp == NULL) ? buf : (cp + 1);
 302                         (void)strlcpy(statp->defdname, cp,
 303                             sizeof(statp->defdname));
 304                 }
 305         }
 306 #endif  /* SOLARIS2 */
 307
 308         /* Allow user to override the local domain definition */
 309         if ((cp = getenv("LOCALDOMAIN")) != NULL) {
 310                 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
 311                 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 312                 haveenv++;
 313
 314                 /*
 315                  * Set search list to be blank-separated strings
 316                  * from rest of env value.  Permits users of LOCALDOMAIN
 317                  * to still have a search list, and anyone to set the
 318                  * one that they want to use as an individual (even more
 319                  * important now that the rfc1535 stuff restricts searches)
 320                  */
 321                 cp = statp->defdname;
 322                 pp = statp->dnsrch;
 323                 *pp++ = cp;
 324                 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
 325                         if (*cp == '\n')        /*%< silly backwards compat */
 326                                 break;
 327                         else if (*cp == ' ' || *cp == '\t') {
 328                                 *cp = 0;
 329                                 n = 1;
 330                         } else if (n) {
 331                                 *pp++ = cp;
 332                                 n = 0;
 333                                 havesearch = 1;
 334                         }
 335                 }
 336                 /* null terminate last domain if there are excess */
 337                 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
 338                         cp++;
 339                 *cp = '\0';
 340                 *pp++ = 0;
 341         }
 342
 343 #define MATCH(line, name) \
 344         (!strncmp(line, name, sizeof(name) - 1) && \
 345         (line[sizeof(name) - 1] == ' ' || \
 346          line[sizeof(name) - 1] == '\t'))
 347
 348         nserv = 0;
 349         if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
 350             struct stat st;
 351             struct kevent kc;
 352
 353             /* read the config file */
 354             while (fgets(buf, sizeof(buf), fp) != NULL) {
 355                 /* skip comments */
 356                 if (*buf == ';' || *buf == '#')
 357                         continue;
 358                 /* read default domain name */
 359                 if (MATCH(buf, "domain")) {
 360                     if (haveenv)        /*%< skip if have from environ */
 361                             continue;
 362                     cp = buf + sizeof("domain") - 1;
 363                     while (*cp == ' ' || *cp == '\t')
 364                             cp++;
 365                     if ((*cp == '\0') || (*cp == '\n'))
 366                             continue;
 367                     strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
 368                     statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 369                     if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
 370                             *cp = '\0';
 371                     havesearch = 0;
 372                     continue;
 373                 }
 374                 /* set search list */
 375                 if (MATCH(buf, "search")) {
 376                     if (haveenv)        /*%< skip if have from environ */
 377                             continue;
 378                     cp = buf + sizeof("search") - 1;
 379                     while (*cp == ' ' || *cp == '\t')
 380                             cp++;
 381                     if ((*cp == '\0') || (*cp == '\n'))
 382                             continue;
 383                     strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
 384                     statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 385                     if ((cp = strchr(statp->defdname, '\n')) != NULL)
 386                             *cp = '\0';
 387                     /*
 388                      * Set search list to be blank-separated strings
 389                      * on rest of line.
 390                      */
 391                     cp = statp->defdname;
 392                     pp = statp->dnsrch;
 393                     *pp++ = cp;
 394                     for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
 395                             if (*cp == ' ' || *cp == '\t') {
 396                                     *cp = 0;
 397                                     n = 1;
 398                             } else if (n) {
 399                                     *pp++ = cp;
 400                                     n = 0;
 401                             }
 402                     }
 403                     /* null terminate last domain if there are excess */
 404                     while (*cp != '\0' && *cp != ' ' && *cp != '\t')
 405                             cp++;
 406                     *cp = '\0';
 407                     *pp++ = 0;
 408                     havesearch = 1;
 409                     continue;
 410                 }
 411                 /* read nameservers to query */
 412                 if (MATCH(buf, "nameserver") && nserv < maxns) {
 413                     struct addrinfo hints, *ai;
 414                     char sbuf[NI_MAXSERV];
 415                     const size_t minsiz =
 416                         sizeof(statp->_u._ext.ext->nsaddrs[0]);
 417
 418                     cp = buf + sizeof("nameserver") - 1;
 419                     while (*cp == ' ' || *cp == '\t')
 420                         cp++;
 421                     cp[strcspn(cp, ";# \t\n")] = '\0';
 422                     if ((*cp != '\0') && (*cp != '\n')) {
 423                         memset(&hints, 0, sizeof(hints));
 424                         hints.ai_family = PF_UNSPEC;
 425                         hints.ai_socktype = SOCK_DGRAM; /*dummy*/
 426                         hints.ai_flags = AI_NUMERICHOST;
 427                         sprintf(sbuf, "%u", NAMESERVER_PORT);
 428                         if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
 429                             ai->ai_addrlen <= minsiz) {
 430                             if (statp->_u._ext.ext != NULL) {
 431                                 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 432                                     ai->ai_addr, ai->ai_addrlen);
 433                             }
 434                             if (ai->ai_addrlen <=
 435                                 sizeof(statp->nsaddr_list[nserv])) {
 436                                 memcpy(&statp->nsaddr_list[nserv],
 437                                     ai->ai_addr, ai->ai_addrlen);
 438                             } else
 439                                 statp->nsaddr_list[nserv].sin_family = 0;
 440                             freeaddrinfo(ai);
 441                             nserv++;
 442                         }
 443                     }
 444                     continue;
 445                 }
 446 #ifdef RESOLVSORT
 447                 if (MATCH(buf, "sortlist")) {
 448                     struct in_addr a;
 449
 450                     cp = buf + sizeof("sortlist") - 1;
 451                     while (nsort < MAXRESOLVSORT) {
 452                         while (*cp == ' ' || *cp == '\t')
 453                             cp++;
 454                         if (*cp == '\0' || *cp == '\n' || *cp == ';')
 455                             break;
 456                         net = cp;
 457                         while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
 458                                isascii(*cp) && !isspace((unsigned char)*cp))
 459                                 cp++;
 460                         n = *cp;
 461                         *cp = 0;
 462                         if (inet_aton(net, &a)) {
 463                             statp->sort_list[nsort].addr = a;
 464                             if (ISSORTMASK(n)) {
 465                                 *cp++ = n;
 466                                 net = cp;
 467                                 while (*cp && *cp != ';' &&
 468                                         isascii(*cp) &&
 469                                         !isspace((unsigned char)*cp))
 470                                     cp++;
 471                                 n = *cp;
 472                                 *cp = 0;
 473                                 if (inet_aton(net, &a)) {
 474                                     statp->sort_list[nsort].mask = a.s_addr;
 475                                 } else {
 476                                     statp->sort_list[nsort].mask =
 477                                         net_mask(statp->sort_list[nsort].addr);
 478                                 }
 479                             } else {
 480                                 statp->sort_list[nsort].mask =
 481                                     net_mask(statp->sort_list[nsort].addr);
 482                             }
 483                             nsort++;
 484                         }
 485                         *cp = n;
 486                     }
 487                     continue;
 488                 }
 489 #endif
 490                 if (MATCH(buf, "options")) {
 491                     res_setoptions(statp, buf + sizeof("options") - 1, "conf");
 492                     continue;
 493                 }
 494             }
 495             if (nserv > 0)
 496                 statp->nscount = nserv;
 497 #ifdef RESOLVSORT
 498             statp->nsort = nsort;
 499 #endif
 500             statp->_u._ext.ext->resfd = dup(fileno(fp));
 501             (void) fclose(fp);
 502             if (fstat(statp->_u._ext.ext->resfd, &st) != -1)
 503                     __res_conf_time = statp->_u._ext.ext->res_conf_time =
 504                         st.st_mtimespec;
 505             statp->_u._ext.ext->kq = kqueue();
 506             (void)fcntl(statp->_u._ext.ext->kq, F_SETFD, FD_CLOEXEC);
 507             (void)fcntl(statp->_u._ext.ext->resfd, F_SETFD, FD_CLOEXEC);
 508             EV_SET(&kc, statp->_u._ext.ext->resfd, EVFILT_VNODE,
 509                 EV_ADD|EV_ENABLE|EV_CLEAR, NOTE_DELETE|NOTE_WRITE| NOTE_EXTEND|
 510                 NOTE_ATTRIB|NOTE_LINK|NOTE_RENAME|NOTE_REVOKE, 0, 0);
 511             (void)kevent(statp->_u._ext.ext->kq, &kc, 1, NULL, 0, &ts);
 512         } else {
 513             statp->_u._ext.ext->kq = -1;
 514             statp->_u._ext.ext->resfd = -1;
 515         }
 516 /*
 517  * Last chance to get a nameserver.  This should not normally
 518  * be necessary
 519  */
 520 #ifdef NO_RESOLV_CONF
 521         if(nserv == 0)
 522                 nserv = get_nameservers(statp);
 523 #endif
 524
 525         if (statp->defdname[0] == 0 &&
 526             gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
 527             (cp = strchr(buf, '.')) != NULL)
 528                 strcpy(statp->defdname, cp + 1);
 529
 530         /* find components of local domain that might be searched */
 531         if (havesearch == 0) {
 532                 pp = statp->dnsrch;
 533                 *pp++ = statp->defdname;
 534                 *pp = NULL;
 535
 536                 dots = 0;
 537                 for (cp = statp->defdname; *cp; cp++)
 538                         dots += (*cp == '.');
 539
 540                 cp = statp->defdname;
 541                 while (pp < statp->dnsrch + MAXDFLSRCH) {
 542                         if (dots < LOCALDOMAINPARTS)
 543                                 break;
 544                         cp = strchr(cp, '.') + 1;    /*%< we know there is one */
 545                         *pp++ = cp;
 546                         dots--;
 547                 }
 548                 *pp = NULL;
 549 #ifdef DEBUG
 550                 if (statp->options & RES_DEBUG) {
 551                         printf(";; res_init()... default dnsrch list:\n");
 552                         for (pp = statp->dnsrch; *pp; pp++)
 553                                 printf(";;\t%s\n", *pp);
 554                         printf(";;\t..END..\n");
 555                 }
 556 #endif
 557         }
 558
 559         if ((cp = getenv("RES_OPTIONS")) != NULL)
 560                 res_setoptions(statp, cp, "env");
 561         statp->options |= RES_INIT;
 562         return (statp->res_h_errno);
 563 }
 564
 565 int
 566 res_check(res_state statp, struct timespec *mtime)
 567 {
 568         /*
 569          * If the times are equal, then we check if there
 570          * was a kevent related to resolv.conf and reload.
 571          * If the times are not equal, then we don't bother
 572          * to check the kevent, because another thread already
 573          * did, loaded and changed the time.
 574          */
 575         if (timespeccmp(&statp->_u._ext.ext->res_conf_time,
 576             &__res_conf_time, ==)) {
 577                 struct kevent ke;
 578                 if (statp->_u._ext.ext->kq == -1)
 579                         goto out;
 580
 581                 switch (kevent(statp->_u._ext.ext->kq, NULL, 0, &ke, 1, &ts)) {
 582                 case 0:
 583                 case -1:
 584 out:
 585                         if (mtime)
 586                                 *mtime = __res_conf_time;
 587                         return 0;
 588                 default:
 589                         break;
 590                 }
 591         }
 592         (void)__res_vinit(statp, 0);
 593         if (mtime)
 594                 *mtime = __res_conf_time;
 595         return 1;
 596 }
 597
 598 static void
 599 res_setoptions(res_state statp, const char *options, const char *source)
 600 {
 601         const char *cp = options;
 602         int i;
 603         struct __res_state_ext *ext = statp->_u._ext.ext;
 604
 605 #ifdef DEBUG
 606         if (statp->options & RES_DEBUG)
 607                 printf(";; res_setoptions(\"%s\", \"%s\")...\n",
 608                        options, source);
 609 #endif
 610         while (*cp) {
 611                 /* skip leading and inner runs of spaces */
 612                 while (*cp == ' ' || *cp == '\t')
 613                         cp++;
 614                 /* search for and process individual options */
 615                 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
 616                         i = atoi(cp + sizeof("ndots:") - 1);
 617                         if (i <= RES_MAXNDOTS)
 618                                 statp->ndots = i;
 619                         else
 620                                 statp->ndots = RES_MAXNDOTS;
 621 #ifdef DEBUG
 622                         if (statp->options & RES_DEBUG)
 623                                 printf(";;\tndots=%d\n", statp->ndots);
 624 #endif
 625                 } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
 626                         i = atoi(cp + sizeof("timeout:") - 1);
 627                         if (i <= RES_MAXRETRANS)
 628                                 statp->retrans = i;
 629                         else
 630                                 statp->retrans = RES_MAXRETRANS;
 631 #ifdef DEBUG
 632                         if (statp->options & RES_DEBUG)
 633                                 printf(";;\ttimeout=%d\n", statp->retrans);
 634 #endif
 635 #ifdef  SOLARIS2
 636                 } else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) {
 637                         /*
 638                          * For backward compatibility, 'retrans' is
 639                          * supported as an alias for 'timeout', though
 640                          * without an imposed maximum.
 641                          */
 642                         statp->retrans = atoi(cp + sizeof("retrans:") - 1);
 643                 } else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){
 644                         /*
 645                          * For backward compatibility, 'retry' is
 646                          * supported as an alias for 'attempts', though
 647                          * without an imposed maximum.
 648                          */
 649                         statp->retry = atoi(cp + sizeof("retry:") - 1);
 650 #endif  /* SOLARIS2 */
 651                 } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
 652                         i = atoi(cp + sizeof("attempts:") - 1);
 653                         if (i <= RES_MAXRETRY)
 654                                 statp->retry = i;
 655                         else
 656                                 statp->retry = RES_MAXRETRY;
 657 #ifdef DEBUG
 658                         if (statp->options & RES_DEBUG)
 659                                 printf(";;\tattempts=%d\n", statp->retry);
 660 #endif
 661                 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
 662 #ifdef DEBUG
 663                         if (!(statp->options & RES_DEBUG)) {
 664                                 printf(";; res_setoptions(\"%s\", \"%s\")..\n",
 665                                        options, source);
 666                                 statp->options |= RES_DEBUG;
 667                         }
 668                         printf(";;\tdebug\n");
 669 #endif
 670                 } else if (!strncmp(cp, "no_tld_query",
 671                                     sizeof("no_tld_query") - 1) ||
 672                            !strncmp(cp, "no-tld-query",
 673                                     sizeof("no-tld-query") - 1)) {
 674                         statp->options |= RES_NOTLDQUERY;
 675                 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
 676                         statp->options |= RES_USE_INET6;
 677                 } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
 678                         statp->options |= RES_ROTATE;
 679                 } else if (!strncmp(cp, "no-check-names",
 680                                     sizeof("no-check-names") - 1)) {
 681                         statp->options |= RES_NOCHECKNAME;
 682                 }
 683 #ifdef RES_USE_EDNS0
 684                 else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
 685                         statp->options |= RES_USE_EDNS0;
 686                 }
 687 #endif
 688                 else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
 689                         statp->options |= RES_USE_DNAME;
 690                 }
 691                 else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
 692                         if (ext == NULL)
 693                                 goto skip;
 694                         cp += sizeof("nibble:") - 1;
 695                         i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
 696                         strncpy(ext->nsuffix, cp, (size_t)i);
 697                         ext->nsuffix[i] = '\0';
 698                 }
 699                 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
 700                         if (ext == NULL)
 701                                 goto skip;
 702                         cp += sizeof("nibble2:") - 1;
 703                         i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
 704                         strncpy(ext->nsuffix2, cp, (size_t)i);
 705                         ext->nsuffix2[i] = '\0';
 706                 }
 707                 else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
 708                         cp += sizeof("v6revmode:") - 1;
 709                         /* "nibble" and "bitstring" used to be valid */
 710                         if (!strncmp(cp, "single", sizeof("single") - 1)) {
 711                                 statp->options |= RES_NO_NIBBLE2;
 712                         } else if (!strncmp(cp, "both", sizeof("both") - 1)) {
 713                                 statp->options &=
 714                                          ~RES_NO_NIBBLE2;
 715                         }
 716                 }
 717                 else {
 718                         /* XXX - print a warning here? */
 719                 }
 720    skip:
 721                 /* skip to next run of spaces */
 722                 while (*cp && *cp != ' ' && *cp != '\t')
 723                         cp++;
 724         }
 725 }
 726
 727 #ifdef RESOLVSORT
 728 /* XXX - should really support CIDR which means explicit masks always. */
 729 static u_int32_t
 730 net_mask(in)            /*!< XXX - should really use system's version of this  */
 731         struct in_addr in;
 732 {
 733         register u_int32_t i = ntohl(in.s_addr);
 734
 735         if (IN_CLASSA(i))
 736                 return (htonl(IN_CLASSA_NET));
 737         else if (IN_CLASSB(i))
 738                 return (htonl(IN_CLASSB_NET));
 739         return (htonl(IN_CLASSC_NET));
 740 }
 741 #endif
 742
 743 static u_char srnd[16];
 744
 745 void
 746 res_rndinit(res_state statp)
 747 {
 748         struct timeval now;
 749         u_int32_t u32;
 750         u_int16_t u16;
 751         u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd;
 752
 753         gettimeofday(&now, NULL);
 754         u32 = (u_int32_t)now.tv_sec;
 755         memcpy(rnd, &u32, 4);
 756         u32 = now.tv_usec;
 757         memcpy(rnd + 4, &u32, 4);
 758         u32 += (u_int32_t)now.tv_sec;
 759         memcpy(rnd + 8, &u32, 4);
 760         u16 = getpid();
 761         memcpy(rnd + 12, &u16, 2);
 762 }
 763
 764 u_int
 765 res_nrandomid(res_state statp) {
 766         struct timeval now;
 767         u_int16_t u16;
 768         MD5_CTX ctx;
 769         u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd;
 770
 771         gettimeofday(&now, NULL);
 772         u16 = (u_int16_t) (now.tv_sec ^ now.tv_usec);
 773         memcpy(rnd + 14, &u16, 2);
 774 #ifndef HAVE_MD5
 775         MD5_Init(&ctx);
 776         MD5_Update(&ctx, rnd, 16);
 777         MD5_Final(rnd, &ctx);
 778 #else
 779         MD5Init(&ctx);
 780         MD5Update(&ctx, rnd, 16);
 781         MD5Final(rnd, &ctx);
 782 #endif
 783         memcpy(&u16, rnd + 14, 2);
 784         return ((u_int) u16);
 785 }
 786
 787 /*%
 788  * This routine is for closing the socket if a virtual circuit is used and
 789  * the program wants to close it.  This provides support for endhostent()
 790  * which expects to close the socket.
 791  *
 792  * This routine is not expected to be user visible.
 793  */
 794 void
 795 res_nclose(res_state statp) {
 796         int ns;
 797
 798         if (statp->_vcsock >= 0) {
 799                 (void) close(statp->_vcsock);
 800                 statp->_vcsock = -1;
 801                 statp->_flags &= ~(RES_F_VC | RES_F_CONN);
 802         }
 803         for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
 804                 if (statp->_u._ext.nssocks[ns] != -1) {
 805                         (void) close(statp->_u._ext.nssocks[ns]);
 806                         statp->_u._ext.nssocks[ns] = -1;
 807                 }
 808         }
 809 }
 810
 811 void
 812 res_ndestroy(res_state statp) {
 813         res_nclose(statp);
 814         if (statp->_u._ext.ext != NULL) {
 815                 if (statp->_u._ext.ext->kq != -1)
 816                         (void)close(statp->_u._ext.ext->kq);
 817                 if (statp->_u._ext.ext->resfd != -1)
 818                         (void)close(statp->_u._ext.ext->resfd);
 819                 free(statp->_u._ext.ext);
 820                 statp->_u._ext.ext = NULL;
 821         }
 822         if (statp->_rnd != NULL) {
 823                 free(statp->_rnd);
 824                 statp->_rnd = NULL;
 825         }
 826         statp->options &= ~RES_INIT;
 827 }
 828
 829 const char *
 830 res_get_nibblesuffix(res_state statp) {
 831         if (statp->_u._ext.ext)
 832                 return (statp->_u._ext.ext->nsuffix);
 833         return ("ip6.arpa");
 834 }
 835
 836 const char *
 837 res_get_nibblesuffix2(res_state statp) {
 838         if (statp->_u._ext.ext)
 839                 return (statp->_u._ext.ext->nsuffix2);
 840         return ("ip6.int");
 841 }
 842
 843 void
 844 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {
 845         int i, nserv;
 846         size_t size;
 847
 848         /* close open servers */
 849         res_nclose(statp);
 850
 851         /* cause rtt times to be forgotten */
 852         statp->_u._ext.nscount = 0;
 853
 854         nserv = 0;
 855         for (i = 0; i < cnt && nserv < MAXNS; i++) {
 856                 switch (set->sin.sin_family) {
 857                 case AF_INET:
 858                         size = sizeof(set->sin);
 859                         if (statp->_u._ext.ext)
 860                                 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 861                                         &set->sin, size);
 862                         if (size <= sizeof(statp->nsaddr_list[nserv]))
 863                                 memcpy(&statp->nsaddr_list[nserv],
 864                                         &set->sin, size);
 865                         else
 866                                 statp->nsaddr_list[nserv].sin_family = 0;
 867                         nserv++;
 868                         break;
 869
 870 #ifdef HAS_INET6_STRUCTS
 871                 case AF_INET6:
 872                         size = sizeof(set->sin6);
 873                         if (statp->_u._ext.ext)
 874                                 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 875                                         &set->sin6, size);
 876                         if (size <= sizeof(statp->nsaddr_list[nserv]))
 877                                 memcpy(&statp->nsaddr_list[nserv],
 878                                         &set->sin6, size);
 879                         else
 880                                 statp->nsaddr_list[nserv].sin_family = 0;
 881                         nserv++;
 882                         break;
 883 #endif
 884
 885                 default:
 886                         break;
 887                 }
 888                 set++;
 889         }
 890         statp->nscount = nserv;
 891
 892 }
 893
 894 int
 895 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {
 896         int i;
 897         size_t size;
 898         u_int16_t family;
 899
 900         for (i = 0; i < statp->nscount && i < cnt; i++) {
 901                 if (statp->_u._ext.ext)
 902                         family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
 903                 else
 904                         family = statp->nsaddr_list[i].sin_family;
 905
 906                 switch (family) {
 907                 case AF_INET:
 908                         size = sizeof(set->sin);
 909                         if (statp->_u._ext.ext)
 910                                 memcpy(&set->sin,
 911                                        &statp->_u._ext.ext->nsaddrs[i],
 912                                        size);
 913                         else
 914                                 memcpy(&set->sin, &statp->nsaddr_list[i],
 915                                        size);
 916                         break;
 917
 918 #ifdef HAS_INET6_STRUCTS
 919                 case AF_INET6:
 920                         size = sizeof(set->sin6);
 921                         if (statp->_u._ext.ext)
 922                                 memcpy(&set->sin6,
 923                                        &statp->_u._ext.ext->nsaddrs[i],
 924                                        size);
 925                         else
 926                                 memcpy(&set->sin6, &statp->nsaddr_list[i],
 927                                        size);
 928                         break;
 929 #endif
 930
 931                 default:
 932                         set->sin.sin_family = 0;
 933                         break;
 934                 }
 935                 set++;
 936         }
 937         return (statp->nscount);
 938 }
 939
 940 /*! \file */