lib/libc/resolv/res_init.c

   1 /*
   2  * @(#)res_init.c       8.1 (Berkeley) 6/7/93
   3  * $Id: res_init.c,v 1.23 2007/07/09 01:43:23 marka Exp $
   4  */
   5
   6 /*
   7  * Copyright (c) 1985, 1989, 1993
   8  *    The Regents of the University of California.  All rights reserved.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 /*
  36  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
  37  *
  38  * Permission to use, copy, modify, and distribute this software for any
  39  * purpose with or without fee is hereby granted, provided that the above
  40  * copyright notice and this permission notice appear in all copies, and that
  41  * the name of Digital Equipment Corporation not be used in advertising or
  42  * publicity pertaining to distribution of the document or software without
  43  * specific, written prior permission.
  44  *
  45  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
  46  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
  47  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
  48  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  49  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  50  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  51  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  52  * SOFTWARE.
  53  */
  54
  55 /*
  56  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
  57  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
  58  *
  59  * Permission to use, copy, modify, and distribute this software for any
  60  * purpose with or without fee is hereby granted, provided that the above
  61  * copyright notice and this permission notice appear in all copies.
  62  *
  63  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
  64  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  65  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  66  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  67  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  68  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  69  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  70  */
  71
  72 #include "port_before.h"
  73
  74 #ifdef _LIBC
  75 #include "namespace.h"
  76 #endif
  77 #include <sys/types.h>
  78 #include <sys/param.h>
  79 #include <sys/socket.h>
  80 #include <sys/time.h>
  81
  82 #include <netinet/in.h>
  83 #include <arpa/inet.h>
  84 #include <arpa/nameser.h>
  85
  86 #include <ctype.h>
  87 #include <stdio.h>
  88 #include <stdlib.h>
  89 #include <string.h>
  90 #include <unistd.h>
  91 #include <netdb.h>
  92 #ifdef _LIBC
  93 #include "un-namespace.h"
  94 #endif
  95
  96 #include "port_after.h"
  97
  98 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
  99 #include <resolv.h>
 100
 101 #include "res_private.h"
 102
 103 /*% Options.  Should all be left alone. */
 104 #define RESOLVSORT
 105 #define DEBUG
 106
 107 #ifdef SOLARIS2
 108 #include <sys/systeminfo.h>
 109 #endif
 110
 111 static void res_setoptions __P((res_state, const char *, const char *));
 112
 113 #ifdef RESOLVSORT
 114 static const char sort_mask[] = "/&";
 115 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
 116 static u_int32_t net_mask __P((struct in_addr));
 117 #endif
 118
 119 #if !defined(isascii)   /*%< XXX - could be a function */
 120 # define isascii(c) (!(c & 0200))
 121 #endif
 122
 123 /*
 124  * Resolver state default settings.
 125  */
 126
 127 /*%
 128  * Set up default settings.  If the configuration file exist, the values
 129  * there will have precedence.  Otherwise, the server address is set to
 130  * INADDR_ANY and the default domain name comes from the gethostname().
 131  *
 132  * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
 133  * rather than INADDR_ANY ("0.0.0.0") as the default name server address
 134  * since it was noted that INADDR_ANY actually meant ``the first interface
 135  * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
 136  * it had to be "up" in order for you to reach your own name server.  It
 137  * was later decided that since the recommended practice is to always
 138  * install local static routes through 127.0.0.1 for all your network
 139  * interfaces, that we could solve this problem without a code change.
 140  *
 141  * The configuration file should always be used, since it is the only way
 142  * to specify a default domain.  If you are running a server on your local
 143  * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
 144  * in the configuration file.
 145  *
 146  * Return 0 if completes successfully, -1 on error
 147  */
 148 int
 149 res_ninit(res_state statp) {
 150         extern int __res_vinit(res_state, int);
 151
 152         return (__res_vinit(statp, 0));
 153 }
 154
 155 /*% This function has to be reachable by res_data.c but not publically. */
 156 int
 157 __res_vinit(res_state statp, int preinit) {
 158         FILE *fp;
 159         char *cp, **pp;
 160         int n;
 161         char buf[BUFSIZ];
 162         int nserv = 0;    /*%< number of nameserver records read from file */
 163         int haveenv = 0;
 164         int havesearch = 0;
 165 #ifdef RESOLVSORT
 166         int nsort = 0;
 167         char *net;
 168 #endif
 169         int dots;
 170         union res_sockaddr_union u[2];
 171         int maxns = MAXNS;
 172
 173         RES_SET_H_ERRNO(statp, 0);
 174         if (statp->_u._ext.ext != NULL)
 175                 res_ndestroy(statp);
 176
 177         if (!preinit) {
 178                 statp->retrans = RES_TIMEOUT;
 179                 statp->retry = RES_DFLRETRY;
 180                 statp->options = RES_DEFAULT;
 181                 statp->id = res_randomid();
 182         }
 183
 184         memset(u, 0, sizeof(u));
 185 #ifdef USELOOPBACK
 186         u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
 187 #else
 188         u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
 189 #endif
 190         u[nserv].sin.sin_family = AF_INET;
 191         u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
 192 #ifdef HAVE_SA_LEN
 193         u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
 194 #endif
 195         nserv++;
 196 #ifdef HAS_INET6_STRUCTS
 197 #ifdef USELOOPBACK
 198         u[nserv].sin6.sin6_addr = in6addr_loopback;
 199 #else
 200         u[nserv].sin6.sin6_addr = in6addr_any;
 201 #endif
 202         u[nserv].sin6.sin6_family = AF_INET6;
 203         u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
 204 #ifdef HAVE_SA_LEN
 205         u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
 206 #endif
 207         nserv++;
 208 #endif
 209         statp->nscount = 0;
 210         statp->ndots = 1;
 211         statp->pfcode = 0;
 212         statp->_vcsock = -1;
 213         statp->_flags = 0;
 214         statp->qhook = NULL;
 215         statp->rhook = NULL;
 216         statp->_u._ext.nscount = 0;
 217         statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
 218         if (statp->_u._ext.ext != NULL) {
 219                 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
 220                 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
 221                 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
 222                 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
 223         } else {
 224                 /*
 225                  * Historically res_init() rarely, if at all, failed.
 226                  * Examples and applications exist which do not check
 227                  * our return code.  Furthermore several applications
 228                  * simply call us to get the systems domainname.  So
 229                  * rather then immediately fail here we store the
 230                  * failure, which is returned later, in h_errno.  And
 231                  * prevent the collection of 'nameserver' information
 232                  * by setting maxns to 0.  Thus applications that fail
 233                  * to check our return code wont be able to make
 234                  * queries anyhow.
 235                  */
 236                 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
 237                 maxns = 0;
 238         }
 239 #ifdef RESOLVSORT
 240         statp->nsort = 0;
 241 #endif
 242         res_setservers(statp, u, nserv);
 243
 244 #ifdef  SOLARIS2
 245         /*
 246          * The old libresolv derived the defaultdomain from NIS/NIS+.
 247          * We want to keep this behaviour
 248          */
 249         {
 250                 char buf[sizeof(statp->defdname)], *cp;
 251                 int ret;
 252
 253                 if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 &&
 254                         (unsigned int)ret <= sizeof(buf)) {
 255                         if (buf[0] == '+')
 256                                 buf[0] = '.';
 257                         cp = strchr(buf, '.');
 258                         cp = (cp == NULL) ? buf : (cp + 1);
 259                         strncpy(statp->defdname, cp,
 260                                 sizeof(statp->defdname) - 1);
 261                         statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 262                 }
 263         }
 264 #endif  /* SOLARIS2 */
 265
 266         /* Allow user to override the local domain definition */
 267         if ((cp = getenv("LOCALDOMAIN")) != NULL) {
 268                 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
 269                 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 270                 haveenv++;
 271
 272                 /*
 273                  * Set search list to be blank-separated strings
 274                  * from rest of env value.  Permits users of LOCALDOMAIN
 275                  * to still have a search list, and anyone to set the
 276                  * one that they want to use as an individual (even more
 277                  * important now that the rfc1535 stuff restricts searches)
 278                  */
 279                 cp = statp->defdname;
 280                 pp = statp->dnsrch;
 281                 *pp++ = cp;
 282                 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
 283                         if (*cp == '\n')        /*%< silly backwards compat */
 284                                 break;
 285                         else if (*cp == ' ' || *cp == '\t') {
 286                                 *cp = 0;
 287                                 n = 1;
 288                         } else if (n) {
 289                                 *pp++ = cp;
 290                                 n = 0;
 291                                 havesearch = 1;
 292                         }
 293                 }
 294                 /* null terminate last domain if there are excess */
 295                 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
 296                         cp++;
 297                 *cp = '\0';
 298                 *pp++ = NULL;
 299         }
 300
 301 #define MATCH(line, name) \
 302         (!strncmp(line, name, sizeof(name) - 1) && \
 303         (line[sizeof(name) - 1] == ' ' || \
 304          line[sizeof(name) - 1] == '\t'))
 305
 306         nserv = 0;
 307         if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
 308             /* read the config file */
 309             while (fgets(buf, sizeof(buf), fp) != NULL) {
 310                 /* skip comments */
 311                 if (*buf == ';' || *buf == '#')
 312                         continue;
 313                 /* read default domain name */
 314                 if (MATCH(buf, "domain")) {
 315                     if (haveenv)        /*%< skip if have from environ */
 316                             continue;
 317                     cp = buf + sizeof("domain") - 1;
 318                     while (*cp == ' ' || *cp == '\t')
 319                             cp++;
 320                     if ((*cp == '\0') || (*cp == '\n'))
 321                             continue;
 322                     strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
 323                     statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 324                     if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
 325                             *cp = '\0';
 326                     havesearch = 0;
 327                     continue;
 328                 }
 329                 /* set search list */
 330                 if (MATCH(buf, "search")) {
 331                     if (haveenv)        /*%< skip if have from environ */
 332                             continue;
 333                     cp = buf + sizeof("search") - 1;
 334                     while (*cp == ' ' || *cp == '\t')
 335                             cp++;
 336                     if ((*cp == '\0') || (*cp == '\n'))
 337                             continue;
 338                     strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
 339                     statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 340                     if ((cp = strchr(statp->defdname, '\n')) != NULL)
 341                             *cp = '\0';
 342                     /*
 343                      * Set search list to be blank-separated strings
 344                      * on rest of line.
 345                      */
 346                     cp = statp->defdname;
 347                     pp = statp->dnsrch;
 348                     *pp++ = cp;
 349                     for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
 350                             if (*cp == ' ' || *cp == '\t') {
 351                                     *cp = 0;
 352                                     n = 1;
 353                             } else if (n) {
 354                                     *pp++ = cp;
 355                                     n = 0;
 356                             }
 357                     }
 358                     /* null terminate last domain if there are excess */
 359                     while (*cp != '\0' && *cp != ' ' && *cp != '\t')
 360                             cp++;
 361                     *cp = '\0';
 362                     *pp++ = NULL;
 363                     havesearch = 1;
 364                     continue;
 365                 }
 366                 /* read nameservers to query */
 367                 if (MATCH(buf, "nameserver") && nserv < maxns) {
 368                     struct addrinfo hints, *ai;
 369                     char sbuf[NI_MAXSERV];
 370                     const size_t minsiz =
 371                         sizeof(statp->_u._ext.ext->nsaddrs[0]);
 372
 373                     cp = buf + sizeof("nameserver") - 1;
 374                     while (*cp == ' ' || *cp == '\t')
 375                         cp++;
 376                     cp[strcspn(cp, ";# \t\n")] = '\0';
 377                     if ((*cp != '\0') && (*cp != '\n')) {
 378                         memset(&hints, 0, sizeof(hints));
 379                         hints.ai_family = PF_UNSPEC;
 380                         hints.ai_socktype = SOCK_DGRAM; /*dummy*/
 381                         hints.ai_flags = AI_NUMERICHOST;
 382                         sprintf(sbuf, "%u", NAMESERVER_PORT);
 383                         if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
 384                             ai->ai_addrlen <= minsiz) {
 385                             if (statp->_u._ext.ext != NULL) {
 386                                 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 387                                     ai->ai_addr, ai->ai_addrlen);
 388                             }
 389                             if (ai->ai_addrlen <=
 390                                 sizeof(statp->nsaddr_list[nserv])) {
 391                                 memcpy(&statp->nsaddr_list[nserv],
 392                                     ai->ai_addr, ai->ai_addrlen);
 393                             } else
 394                                 statp->nsaddr_list[nserv].sin_family = 0;
 395                             freeaddrinfo(ai);
 396                             nserv++;
 397                         }
 398                     }
 399                     continue;
 400                 }
 401 #ifdef RESOLVSORT
 402                 if (MATCH(buf, "sortlist")) {
 403                     struct in_addr a;
 404
 405                     cp = buf + sizeof("sortlist") - 1;
 406                     while (nsort < MAXRESOLVSORT) {
 407                         while (*cp == ' ' || *cp == '\t')
 408                             cp++;
 409                         if (*cp == '\0' || *cp == '\n' || *cp == ';')
 410                             break;
 411                         net = cp;
 412                         while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
 413                                isascii(*cp) && !isspace((unsigned char)*cp))
 414                                 cp++;
 415                         n = *cp;
 416                         *cp = 0;
 417                         if (inet_aton(net, &a)) {
 418                             statp->sort_list[nsort].addr = a;
 419                             if (ISSORTMASK(n)) {
 420                                 *cp++ = n;
 421                                 net = cp;
 422                                 while (*cp && *cp != ';' &&
 423                                         isascii(*cp) &&
 424                                         !isspace((unsigned char)*cp))
 425                                     cp++;
 426                                 n = *cp;
 427                                 *cp = 0;
 428                                 if (inet_aton(net, &a)) {
 429                                     statp->sort_list[nsort].mask = a.s_addr;
 430                                 } else {
 431                                     statp->sort_list[nsort].mask =
 432                                         net_mask(statp->sort_list[nsort].addr);
 433                                 }
 434                             } else {
 435                                 statp->sort_list[nsort].mask =
 436                                     net_mask(statp->sort_list[nsort].addr);
 437                             }
 438                             nsort++;
 439                         }
 440                         *cp = n;
 441                     }
 442                     continue;
 443                 }
 444 #endif
 445                 if (MATCH(buf, "options"))
 446                     res_setoptions(statp, buf + sizeof("options") - 1, "conf");
 447             }
 448             if (nserv > 0)
 449                 statp->nscount = nserv;
 450 #ifdef RESOLVSORT
 451             statp->nsort = nsort;
 452 #endif
 453             (void) fclose(fp);
 454         }
 455 /*
 456  * Last chance to get a nameserver.  This should not normally
 457  * be necessary
 458  */
 459 #ifdef NO_RESOLV_CONF
 460         if(nserv == 0)
 461                 nserv = get_nameservers(statp);
 462 #endif
 463
 464         if (statp->defdname[0] == 0 &&
 465             gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
 466             (cp = strchr(buf, '.')) != NULL)
 467                 strcpy(statp->defdname, cp + 1);
 468
 469         /* find components of local domain that might be searched */
 470         if (havesearch == 0) {
 471                 pp = statp->dnsrch;
 472                 *pp++ = statp->defdname;
 473                 *pp = NULL;
 474
 475                 dots = 0;
 476                 for (cp = statp->defdname; *cp; cp++)
 477                         dots += (*cp == '.');
 478
 479                 cp = statp->defdname;
 480                 while (pp < statp->dnsrch + MAXDFLSRCH) {
 481                         if (dots < LOCALDOMAINPARTS)
 482                                 break;
 483                         cp = strchr(cp, '.') + 1;    /*%< we know there is one */
 484                         *pp++ = cp;
 485                         dots--;
 486                 }
 487                 *pp = NULL;
 488 #ifdef DEBUG
 489                 if (statp->options & RES_DEBUG) {
 490                         printf(";; res_init()... default dnsrch list:\n");
 491                         for (pp = statp->dnsrch; *pp; pp++)
 492                                 printf(";;\t%s\n", *pp);
 493                         printf(";;\t..END..\n");
 494                 }
 495 #endif
 496         }
 497
 498         if ((cp = getenv("RES_OPTIONS")) != NULL)
 499                 res_setoptions(statp, cp, "env");
 500         statp->options |= RES_INIT;
 501         return (statp->res_h_errno);
 502 }
 503
 504 static void
 505 res_setoptions(res_state statp, const char *options, const char *source)
 506 {
 507         const char *cp = options;
 508         int i;
 509 #ifndef _LIBC
 510         struct __res_state_ext *ext = statp->_u._ext.ext;
 511 #endif
 512
 513 #ifdef DEBUG
 514         if (statp->options & RES_DEBUG)
 515                 printf(";; res_setoptions(\"%s\", \"%s\")...\n",
 516                        options, source);
 517 #endif
 518         while (*cp) {
 519                 /* skip leading and inner runs of spaces */
 520                 while (*cp == ' ' || *cp == '\t')
 521                         cp++;
 522                 /* search for and process individual options */
 523                 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
 524                         i = atoi(cp + sizeof("ndots:") - 1);
 525                         if (i <= RES_MAXNDOTS)
 526                                 statp->ndots = i;
 527                         else
 528                                 statp->ndots = RES_MAXNDOTS;
 529 #ifdef DEBUG
 530                         if (statp->options & RES_DEBUG)
 531                                 printf(";;\tndots=%d\n", statp->ndots);
 532 #endif
 533                 } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
 534                         i = atoi(cp + sizeof("timeout:") - 1);
 535                         if (i <= RES_MAXRETRANS)
 536                                 statp->retrans = i;
 537                         else
 538                                 statp->retrans = RES_MAXRETRANS;
 539 #ifdef DEBUG
 540                         if (statp->options & RES_DEBUG)
 541                                 printf(";;\ttimeout=%d\n", statp->retrans);
 542 #endif
 543 #ifdef  SOLARIS2
 544                 } else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) {
 545                         /*
 546                          * For backward compatibility, 'retrans' is
 547                          * supported as an alias for 'timeout', though
 548                          * without an imposed maximum.
 549                          */
 550                         statp->retrans = atoi(cp + sizeof("retrans:") - 1);
 551                 } else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){
 552                         /*
 553                          * For backward compatibility, 'retry' is
 554                          * supported as an alias for 'attempts', though
 555                          * without an imposed maximum.
 556                          */
 557                         statp->retry = atoi(cp + sizeof("retry:") - 1);
 558 #endif  /* SOLARIS2 */
 559                 } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
 560                         i = atoi(cp + sizeof("attempts:") - 1);
 561                         if (i <= RES_MAXRETRY)
 562                                 statp->retry = i;
 563                         else
 564                                 statp->retry = RES_MAXRETRY;
 565 #ifdef DEBUG
 566                         if (statp->options & RES_DEBUG)
 567                                 printf(";;\tattempts=%d\n", statp->retry);
 568 #endif
 569                 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
 570 #ifdef DEBUG
 571                         if (!(statp->options & RES_DEBUG)) {
 572                                 printf(";; res_setoptions(\"%s\", \"%s\")..\n",
 573                                        options, source);
 574                                 statp->options |= RES_DEBUG;
 575                         }
 576                         printf(";;\tdebug\n");
 577 #endif
 578                 } else if (!strncmp(cp, "no_tld_query",
 579                                     sizeof("no_tld_query") - 1) ||
 580                            !strncmp(cp, "no-tld-query",
 581                                     sizeof("no-tld-query") - 1)) {
 582                         statp->options |= RES_NOTLDQUERY;
 583                 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
 584                         statp->options |= RES_USE_INET6;
 585                 } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
 586                         statp->options |= RES_ROTATE;
 587                 } else if (!strncmp(cp, "no-check-names",
 588                                     sizeof("no-check-names") - 1)) {
 589                         statp->options |= RES_NOCHECKNAME;
 590                 }
 591 #ifdef RES_USE_EDNS0
 592                 else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
 593                         statp->options |= RES_USE_EDNS0;
 594                 }
 595 #endif
 596 #ifndef _LIBC
 597                 else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
 598                         statp->options |= RES_USE_DNAME;
 599                 }
 600                 else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
 601                         if (ext == NULL)
 602                                 goto skip;
 603                         cp += sizeof("nibble:") - 1;
 604                         i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
 605                         strncpy(ext->nsuffix, cp, i);
 606                         ext->nsuffix[i] = '\0';
 607                 }
 608                 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
 609                         if (ext == NULL)
 610                                 goto skip;
 611                         cp += sizeof("nibble2:") - 1;
 612                         i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
 613                         strncpy(ext->nsuffix2, cp, i);
 614                         ext->nsuffix2[i] = '\0';
 615                 }
 616                 else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
 617                         cp += sizeof("v6revmode:") - 1;
 618                         /* "nibble" and "bitstring" used to be valid */
 619                         if (!strncmp(cp, "single", sizeof("single") - 1)) {
 620                                 statp->options |= RES_NO_NIBBLE2;
 621                         } else if (!strncmp(cp, "both", sizeof("both") - 1)) {
 622                                 statp->options &=
 623                                          ~RES_NO_NIBBLE2;
 624                         }
 625                 }
 626 #endif
 627                 else {
 628                         /* XXX - print a warning here? */
 629                 }
 630 #ifndef _LIBC
 631    skip:
 632 #endif
 633                 /* skip to next run of spaces */
 634                 while (*cp && *cp != ' ' && *cp != '\t')
 635                         cp++;
 636         }
 637 }
 638
 639 #ifdef RESOLVSORT
 640 /* XXX - should really support CIDR which means explicit masks always. */
 641 static u_int32_t
 642 net_mask(struct in_addr in)             /*!< XXX - should really use system's version of this  */
 643 {
 644         u_int32_t i = ntohl(in.s_addr);
 645
 646         if (IN_CLASSA(i))
 647                 return (htonl(IN_CLASSA_NET));
 648         else if (IN_CLASSB(i))
 649                 return (htonl(IN_CLASSB_NET));
 650         return (htonl(IN_CLASSC_NET));
 651 }
 652 #endif
 653
 654 u_int
 655 res_randomid(void) {
 656         struct timeval now;
 657
 658         gettimeofday(&now, NULL);
 659         return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid()));
 660 }
 661
 662 /*%
 663  * This routine is for closing the socket if a virtual circuit is used and
 664  * the program wants to close it.  This provides support for endhostent()
 665  * which expects to close the socket.
 666  *
 667  * This routine is not expected to be user visible.
 668  */
 669 void
 670 res_nclose(res_state statp) {
 671         int ns;
 672
 673         if (statp->_vcsock >= 0) {
 674 #ifndef _LIBC
 675                 (void) close(statp->_vcsock);
 676 #else
 677                 _close(statp->_vcsock);
 678 #endif
 679                 statp->_vcsock = -1;
 680                 statp->_flags &= ~(RES_F_VC | RES_F_CONN);
 681         }
 682         for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
 683                 if (statp->_u._ext.nssocks[ns] != -1) {
 684 #ifndef _LIBC
 685                         (void) close(statp->_u._ext.nssocks[ns]);
 686 #else
 687                         _close(statp->_u._ext.nssocks[ns]);
 688 #endif
 689                         statp->_u._ext.nssocks[ns] = -1;
 690                 }
 691         }
 692 }
 693
 694 void
 695 res_ndestroy(res_state statp) {
 696         res_nclose(statp);
 697         if (statp->_u._ext.ext != NULL)
 698                 free(statp->_u._ext.ext);
 699         statp->options &= ~RES_INIT;
 700         statp->_u._ext.ext = NULL;
 701 }
 702
 703 #ifndef _LIBC
 704 const char *
 705 res_get_nibblesuffix(res_state statp) {
 706         if (statp->_u._ext.ext)
 707                 return (statp->_u._ext.ext->nsuffix);
 708         return ("ip6.arpa");
 709 }
 710
 711 const char *
 712 res_get_nibblesuffix2(res_state statp) {
 713         if (statp->_u._ext.ext)
 714                 return (statp->_u._ext.ext->nsuffix2);
 715         return ("ip6.int");
 716 }
 717 #endif
 718
 719 void
 720 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {
 721         int i, nserv;
 722         size_t size;
 723
 724         /* close open servers */
 725         res_nclose(statp);
 726
 727         /* cause rtt times to be forgotten */
 728         statp->_u._ext.nscount = 0;
 729
 730         nserv = 0;
 731         for (i = 0; i < cnt && nserv < MAXNS; i++) {
 732                 switch (set->sin.sin_family) {
 733                 case AF_INET:
 734                         size = sizeof(set->sin);
 735                         if (statp->_u._ext.ext)
 736                                 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 737                                         &set->sin, size);
 738                         if (size <= sizeof(statp->nsaddr_list[nserv]))
 739                                 memcpy(&statp->nsaddr_list[nserv],
 740                                         &set->sin, size);
 741                         else
 742                                 statp->nsaddr_list[nserv].sin_family = 0;
 743                         nserv++;
 744                         break;
 745
 746 #ifdef HAS_INET6_STRUCTS
 747                 case AF_INET6:
 748                         size = sizeof(set->sin6);
 749                         if (statp->_u._ext.ext)
 750                                 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 751                                         &set->sin6, size);
 752                         if (size <= sizeof(statp->nsaddr_list[nserv]))
 753                                 memcpy(&statp->nsaddr_list[nserv],
 754                                         &set->sin6, size);
 755                         else
 756                                 statp->nsaddr_list[nserv].sin_family = 0;
 757                         nserv++;
 758                         break;
 759 #endif
 760
 761                 default:
 762                         break;
 763                 }
 764                 set++;
 765         }
 766         statp->nscount = nserv;
 767
 768 }
 769
 770 int
 771 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {
 772         int i;
 773         size_t size;
 774         u_int16_t family;
 775
 776         for (i = 0; i < statp->nscount && i < cnt; i++) {
 777                 if (statp->_u._ext.ext)
 778                         family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
 779                 else
 780                         family = statp->nsaddr_list[i].sin_family;
 781
 782                 switch (family) {
 783                 case AF_INET:
 784                         size = sizeof(set->sin);
 785                         if (statp->_u._ext.ext)
 786                                 memcpy(&set->sin,
 787                                        &statp->_u._ext.ext->nsaddrs[i],
 788                                        size);
 789                         else
 790                                 memcpy(&set->sin, &statp->nsaddr_list[i],
 791                                        size);
 792                         break;
 793
 794 #ifdef HAS_INET6_STRUCTS
 795                 case AF_INET6:
 796                         size = sizeof(set->sin6);
 797                         if (statp->_u._ext.ext)
 798                                 memcpy(&set->sin6,
 799                                        &statp->_u._ext.ext->nsaddrs[i],
 800                                        size);
 801                         else
 802                                 memcpy(&set->sin6, &statp->nsaddr_list[i],
 803                                        size);
 804                         break;
 805 #endif
 806
 807                 default:
 808                         set->sin.sin_family = 0;
 809                         break;
 810                 }
 811                 set++;
 812         }
 813         return (statp->nscount);
 814 }
 815 /*! \file */