other-licenses/android/res_init.c

   1 /*      $NetBSD: res_init.c,v 1.8 2006/03/19 03:10:08 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 /*
  74  * This version of this file is derived from Android 2.3 "Gingerbread",
  75  * which contains uncredited changes by Android/Google developers.  It has
  76  * been modified in 2011 for use in the Android build of Mozilla Firefox by
  77  * Mozilla contributors (including Michael Edwards <m.k.edwards@gmail.com>,
  78  * and Steve Workman <sjhworkman@gmail.com>).
  79  * These changes are offered under the same license as the original NetBSD
  80  * file, whose copyright and license are unchanged above.
  81  */
  82
  83 #define ANDROID_CHANGES 1
  84 #define MOZILLE_NECKO_EXCLUDE_CODE 1
  85
  86 #include <sys/cdefs.h>
  87 #if defined(LIBC_SCCS) && !defined(lint)
  88 #ifdef notdef
  89 static const char sccsid[] = "@(#)res_init.c    8.1 (Berkeley) 6/7/93";
  90 static const char rcsid[] = "Id: res_init.c,v 1.9.2.5.4.2 2004/03/16 12:34:18 marka Exp";
  91 #else
  92 __RCSID("$NetBSD: res_init.c,v 1.8 2006/03/19 03:10:08 christos Exp $");
  93 #endif
  94 #endif /* LIBC_SCCS and not lint */
  95
  96
  97
  98 #include <sys/types.h>
  99 #include <sys/param.h>
 100 #include <sys/socket.h>
 101 #include <sys/time.h>
 102
 103 #include <netinet/in.h>
 104 #include <arpa/inet.h>
 105 #include "arpa_nameser.h"
 106
 107 #include <ctype.h>
 108 #include <stdio.h>
 109 #include <stdlib.h>
 110 #include <string.h>
 111 #include <unistd.h>
 112 #include <netdb.h>
 113
 114 #ifdef ANDROID_CHANGES
 115 #include <sys/system_properties.h>
 116 #endif /* ANDROID_CHANGES */
 117
 118 #ifndef MIN
 119 #define MIN(x,y)        ((x)<(y)?(x):(y))
 120 #endif
 121
 122 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
 123 #ifdef ANDROID_CHANGES
 124 #include "resolv_private.h"
 125 #define MAX_DNS_PROPERTIES 8
 126 #define DNS_PROP_NAME_PREFIX "net.dns"
 127 #define DNS_CHANGE_PROP_NAME "net.dnschange"
 128 #define DNS_SEARCH_PROP_NAME "net.dns.search"
 129 const prop_info *dns_change_prop;
 130 int dns_last_change_counter;
 131 static int _get_dns_change_count();
 132 #else
 133 #include <resolv.h>
 134 #endif
 135
 136 #include "res_private.h"
 137
 138 /* Options.  Should all be left alone. */
 139 #ifndef DEBUG
 140 #define DEBUG
 141 #endif
 142
 143 static void res_setoptions __P((res_state, const char *, const char *));
 144
 145 static const char sort_mask[] = "/&";
 146 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
 147 static u_int32_t net_mask __P((struct in_addr));
 148
 149 #if !defined(isascii)   /* XXX - could be a function */
 150 # define isascii(c) (!(c & 0200))
 151 #endif
 152
 153 /*
 154  * Resolver state default settings.
 155  */
 156
 157 /*
 158  * Set up default settings.  If the configuration file exist, the values
 159  * there will have precedence.  Otherwise, the server address is set to
 160  * INADDR_ANY and the default domain name comes from the gethostname().
 161  *
 162  * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
 163  * rather than INADDR_ANY ("0.0.0.0") as the default name server address
 164  * since it was noted that INADDR_ANY actually meant ``the first interface
 165  * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
 166  * it had to be "up" in order for you to reach your own name server.  It
 167  * was later decided that since the recommended practice is to always
 168  * install local static routes through 127.0.0.1 for all your network
 169  * interfaces, that we could solve this problem without a code change.
 170  *
 171  * The configuration file should always be used, since it is the only way
 172  * to specify a default domain.  If you are running a server on your local
 173  * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
 174  * in the configuration file.
 175  *
 176  * Return 0 if completes successfully, -1 on error
 177  */
 178 int
 179 res_ninit(res_state statp) {
 180         extern int __res_vinit(res_state, int);
 181
 182         return (__res_vinit(statp, 0));
 183 }
 184
 185 #ifdef ANDROID_CHANGES
 186 int load_domain_search_list(res_state statp) {
 187         char propvalue[PROP_VALUE_MAX];
 188         register char *cp, **pp;
 189
 190         if(__system_property_get(DNS_SEARCH_PROP_NAME, propvalue) >= 1) {
 191                 strlcpy(statp->defdname, propvalue, sizeof(statp->defdname));
 192                 if ((cp = strchr(statp->defdname, '\n')) != NULL)
 193                         *cp = '\0';
 194                 cp = statp->defdname;
 195                 pp = statp->dnsrch;
 196                 while ( pp < statp->dnsrch + MAXDNSRCH ) {
 197                         while (*cp == ' ' || *cp == '\t') /* skip leading white space */
 198                                 cp++;
 199                         if (*cp == '\0')  /* stop if nothing more */
 200                                 break;
 201                         *pp++ = cp;  /* record this search domain */
 202                         while (*cp) { /* zero-terminate it */
 203                                 if (*cp == ' ' || *cp == '\t') {
 204                                         *cp++ = '\0';
 205                                         break;
 206                                 }
 207                                 cp++;
 208                         }
 209                 }
 210                 *pp = NULL; /* statp->dnsrch has MAXDNSRCH+1 items */
 211                 if (pp > statp->dnsrch)
 212                         return 1;
 213         }
 214         statp->defdname[0] = '\0';  /* no default domain name on Android */
 215         statp->dnsrch[0] = NULL;
 216         return 0;
 217 }
 218 #endif
 219
 220 /* This function has to be reachable by res_data.c but not publicly. */
 221 int
 222 __res_vinit(res_state statp, int preinit) {
 223         register FILE *fp;
 224         register char *cp, **pp;
 225         register int n;
 226         char buf[BUFSIZ];
 227         int nserv = 0;    /* number of nameserver records read from file */
 228         int haveenv = 0;
 229         int havesearch = 0;
 230         int nsort = 0;
 231         char *net;
 232         int dots;
 233         union res_sockaddr_union u[2];
 234 #ifdef ANDROID_CHANGES
 235         pid_t mypid = getpid();
 236         int use_proc_props = 0;
 237         int found_prop;
 238         char dnsProperty[PROP_VALUE_MAX];
 239 #endif
 240
 241         if (!preinit) {
 242                 statp->retrans = RES_TIMEOUT;
 243                 statp->retry = RES_DFLRETRY;
 244                 statp->options = RES_DEFAULT;
 245                 statp->id = res_randomid();
 246         }
 247
 248   if ((statp->options & RES_INIT) != 0U)
 249        res_ndestroy(statp);
 250
 251         memset(u, 0, sizeof(u));
 252 #ifdef USELOOPBACK
 253         u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
 254 #else
 255         u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
 256 #endif
 257         u[nserv].sin.sin_family = AF_INET;
 258         u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
 259 #ifdef HAVE_SA_LEN
 260         u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
 261 #endif
 262         nserv++;
 263 #ifdef HAS_INET6_STRUCTS
 264 #ifdef USELOOPBACK
 265         u[nserv].sin6.sin6_addr = in6addr_loopback;
 266 #else
 267         u[nserv].sin6.sin6_addr = in6addr_any;
 268 #endif
 269         u[nserv].sin6.sin6_family = AF_INET6;
 270         u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
 271 #ifdef HAVE_SA_LEN
 272         u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
 273 #endif
 274         nserv++;
 275 #endif
 276         statp->nscount = 0;
 277         statp->ndots = 1;
 278         statp->pfcode = 0;
 279         statp->_vcsock = -1;
 280         statp->_flags = 0;
 281         statp->qhook = NULL;
 282         statp->rhook = NULL;
 283         statp->_u._ext.nscount = 0;
 284         statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
 285         if (statp->_u._ext.ext != NULL) {
 286                 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
 287                 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
 288                 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
 289                 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
 290         }
 291         statp->nsort = 0;
 292         res_setservers(statp, u, nserv);
 293
 294 #if 0 /* IGNORE THE ENVIRONMENT */
 295         /* Allow user to override the local domain definition */
 296         if ((cp = getenv("LOCALDOMAIN")) != NULL) {
 297                 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
 298                 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 299                 haveenv++;
 300
 301                 /*
 302                  * Set search list to be blank-separated strings
 303                  * from rest of env value.  Permits users of LOCALDOMAIN
 304                  * to still have a search list, and anyone to set the
 305                  * one that they want to use as an individual (even more
 306                  * important now that the rfc1535 stuff restricts searches)
 307                  */
 308                 cp = statp->defdname;
 309                 pp = statp->dnsrch;
 310                 *pp++ = cp;
 311                 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
 312                         if (*cp == '\n')        /* silly backwards compat */
 313                                 break;
 314                         else if (*cp == ' ' || *cp == '\t') {
 315                                 *cp = 0;
 316                                 n = 1;
 317                         } else if (n) {
 318                                 *pp++ = cp;
 319                                 n = 0;
 320                                 havesearch = 1;
 321                         }
 322                 }
 323                 /* null terminate last domain if there are excess */
 324                 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
 325                         cp++;
 326                 *cp = '\0';
 327                 *pp++ = 0;
 328         }
 329         if (nserv > 0)
 330                 statp->nscount = nserv;
 331 #endif
 332 #ifdef ANDROID_CHANGES /* READ FROM SYSTEM PROPERTIES */
 333         dns_last_change_counter = _get_dns_change_count();
 334
 335         nserv = 0;
 336         for(n = 1; n <= MAX_DNS_PROPERTIES && nserv < MAXNS; n++) {
 337                 char propname[PROP_NAME_MAX];
 338                 char propvalue[PROP_VALUE_MAX];
 339
 340                 struct addrinfo hints, *ai;
 341                 char sbuf[NI_MAXSERV];
 342                 const size_t minsiz = sizeof(statp->_u._ext.ext->nsaddrs[0]);
 343
 344                 /*
 345                  * Check first for process-specific properties, and if those don't
 346                  * exist, try the generic properties.
 347                  */
 348                 found_prop = 0;
 349                 if (n == 1 || use_proc_props) {
 350                         snprintf(propname, sizeof(propname), "%s%d.%d", DNS_PROP_NAME_PREFIX, n, mypid);
 351                         if(__system_property_get(propname, propvalue) < 1) {
 352                                 if (use_proc_props) {
 353                                         break;
 354                                 }
 355                         } else {
 356                                 found_prop = 1;
 357                                 use_proc_props = 1;
 358                         }
 359                 }
 360                 if (!found_prop) {
 361                         snprintf(propname, sizeof(propname), "%s%d", DNS_PROP_NAME_PREFIX, n);
 362                         if(__system_property_get(propname, propvalue) < 1) {
 363                                 break;
 364                         }
 365                 }
 366
 367                 cp = propvalue;
 368
 369                 while (*cp == ' ' || *cp == '\t')
 370                         cp++;
 371                 cp[strcspn(cp, ";# \t\n")] = '\0';
 372                 if ((*cp != '\0') && (*cp != '\n')) {
 373                         memset(&hints, 0, sizeof(hints));
 374                         hints.ai_family = PF_UNSPEC;
 375                         hints.ai_socktype = SOCK_DGRAM; /*dummy*/
 376                         hints.ai_flags = AI_NUMERICHOST;
 377                         sprintf(sbuf, "%u", NAMESERVER_PORT);
 378                         if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
 379                             (size_t)ai->ai_addrlen <= minsiz) {
 380                                 if (statp->_u._ext.ext != NULL) {
 381                                         memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 382                                                ai->ai_addr, ai->ai_addrlen);
 383                                 }
 384                                 if ((size_t)ai->ai_addrlen <=
 385                                     sizeof(statp->nsaddr_list[nserv])) {
 386                                         memcpy(&statp->nsaddr_list[nserv],
 387                                                ai->ai_addr, ai->ai_addrlen);
 388                                 } else {
 389                                         statp->nsaddr_list[nserv].sin_family = 0;
 390                                 }
 391                                 freeaddrinfo(ai);
 392                                 nserv++;
 393                         }
 394                 }
 395         }
 396
 397         /* Add the domain search list */
 398         havesearch = load_domain_search_list(statp);
 399 #else /* !ANDROID_CHANGES - IGNORE resolv.conf in Android */
 400 #define MATCH(line, name) \
 401         (!strncmp(line, name, sizeof(name) - 1) && \
 402         (line[sizeof(name) - 1] == ' ' || \
 403          line[sizeof(name) - 1] == '\t'))
 404
 405         nserv = 0;
 406         if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
 407             /* read the config file */
 408             while (fgets(buf, sizeof(buf), fp) != NULL) {
 409                 /* skip comments */
 410                 if (*buf == ';' || *buf == '#')
 411                         continue;
 412                 /* read default domain name */
 413                 if (MATCH(buf, "domain")) {
 414                     if (haveenv)        /* skip if have from environ */
 415                             continue;
 416                     cp = buf + sizeof("domain") - 1;
 417                     while (*cp == ' ' || *cp == '\t')
 418                             cp++;
 419                     if ((*cp == '\0') || (*cp == '\n'))
 420                             continue;
 421                     strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
 422                     statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 423                     if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
 424                             *cp = '\0';
 425                     havesearch = 0;
 426                     continue;
 427                 }
 428                 /* set search list */
 429                 if (MATCH(buf, "search")) {
 430                     if (haveenv)        /* skip if have from environ */
 431                             continue;
 432                     cp = buf + sizeof("search") - 1;
 433                     while (*cp == ' ' || *cp == '\t')
 434                             cp++;
 435                     if ((*cp == '\0') || (*cp == '\n'))
 436                             continue;
 437                     strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
 438                     statp->defdname[sizeof(statp->defdname) - 1] = '\0';
 439                     if ((cp = strchr(statp->defdname, '\n')) != NULL)
 440                             *cp = '\0';
 441                     /*
 442                      * Set search list to be blank-separated strings
 443                      * on rest of line.
 444                      */
 445                     cp = statp->defdname;
 446                     pp = statp->dnsrch;
 447                     *pp++ = cp;
 448                     for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
 449                             if (*cp == ' ' || *cp == '\t') {
 450                                     *cp = 0;
 451                                     n = 1;
 452                             } else if (n) {
 453                                     *pp++ = cp;
 454                                     n = 0;
 455                             }
 456                     }
 457                     /* null terminate last domain if there are excess */
 458                     while (*cp != '\0' && *cp != ' ' && *cp != '\t')
 459                             cp++;
 460                     *cp = '\0';
 461                     *pp++ = 0;
 462                     havesearch = 1;
 463                     continue;
 464                 }
 465                 /* read nameservers to query */
 466                 if (MATCH(buf, "nameserver") && nserv < MAXNS) {
 467                     struct addrinfo hints, *ai;
 468                     char sbuf[NI_MAXSERV];
 469                     const size_t minsiz =
 470                         sizeof(statp->_u._ext.ext->nsaddrs[0]);
 471
 472                     cp = buf + sizeof("nameserver") - 1;
 473                     while (*cp == ' ' || *cp == '\t')
 474                         cp++;
 475                     cp[strcspn(cp, ";# \t\n")] = '\0';
 476                     if ((*cp != '\0') && (*cp != '\n')) {
 477                         memset(&hints, 0, sizeof(hints));
 478                         hints.ai_family = PF_UNSPEC;
 479                         hints.ai_socktype = SOCK_DGRAM; /*dummy*/
 480                         hints.ai_flags = AI_NUMERICHOST;
 481                         sprintf(sbuf, "%u", NAMESERVER_PORT);
 482                         if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
 483                             ai->ai_addrlen <= minsiz) {
 484                             if (statp->_u._ext.ext != NULL) {
 485                                 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 486                                     ai->ai_addr, ai->ai_addrlen);
 487                             }
 488                             if (ai->ai_addrlen <=
 489                                 sizeof(statp->nsaddr_list[nserv])) {
 490                                 memcpy(&statp->nsaddr_list[nserv],
 491                                     ai->ai_addr, ai->ai_addrlen);
 492                             } else
 493                                 statp->nsaddr_list[nserv].sin_family = 0;
 494                             freeaddrinfo(ai);
 495                             nserv++;
 496                         }
 497                     }
 498                     continue;
 499                 }
 500                 if (MATCH(buf, "sortlist")) {
 501                     struct in_addr a;
 502
 503                     cp = buf + sizeof("sortlist") - 1;
 504                     while (nsort < MAXRESOLVSORT) {
 505                         while (*cp == ' ' || *cp == '\t')
 506                             cp++;
 507                         if (*cp == '\0' || *cp == '\n' || *cp == ';')
 508                             break;
 509                         net = cp;
 510                         while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
 511                                isascii(*cp) && !isspace((unsigned char)*cp))
 512                                 cp++;
 513                         n = *cp;
 514                         *cp = 0;
 515                         if (inet_aton(net, &a)) {
 516                             statp->sort_list[nsort].addr = a;
 517                             if (ISSORTMASK(n)) {
 518                                 *cp++ = n;
 519                                 net = cp;
 520                                 while (*cp && *cp != ';' &&
 521                                         isascii(*cp) &&
 522                                         !isspace((unsigned char)*cp))
 523                                     cp++;
 524                                 n = *cp;
 525                                 *cp = 0;
 526                                 if (inet_aton(net, &a)) {
 527                                     statp->sort_list[nsort].mask = a.s_addr;
 528                                 } else {
 529                                     statp->sort_list[nsort].mask =
 530                                         net_mask(statp->sort_list[nsort].addr);
 531                                 }
 532                             } else {
 533                                 statp->sort_list[nsort].mask =
 534                                     net_mask(statp->sort_list[nsort].addr);
 535                             }
 536                             nsort++;
 537                         }
 538                         *cp = n;
 539                     }
 540                     continue;
 541                 }
 542                 if (MATCH(buf, "options")) {
 543                     res_setoptions(statp, buf + sizeof("options") - 1, "conf");
 544                     continue;
 545                 }
 546             }
 547             if (nserv > 0)
 548                 statp->nscount = nserv;
 549             statp->nsort = nsort;
 550             (void) fclose(fp);
 551         }
 552 #endif /* !ANDROID_CHANGES */
 553 /*
 554  * Last chance to get a nameserver.  This should not normally
 555  * be necessary
 556  */
 557 #ifdef NO_RESOLV_CONF
 558         if(nserv == 0)
 559                 nserv = get_nameservers(statp);
 560 #endif
 561
 562         if (statp->defdname[0] == 0 &&
 563             gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
 564             (cp = strchr(buf, '.')) != NULL)
 565                 strcpy(statp->defdname, cp + 1);
 566
 567         /* find components of local domain that might be searched */
 568         if (havesearch == 0) {
 569                 pp = statp->dnsrch;
 570                 *pp++ = statp->defdname;
 571                 *pp = NULL;
 572
 573                 dots = 0;
 574                 for (cp = statp->defdname; *cp; cp++)
 575                         dots += (*cp == '.');
 576
 577                 cp = statp->defdname;
 578                 while (pp < statp->dnsrch + MAXDFLSRCH) {
 579                         if (dots < LOCALDOMAINPARTS)
 580                                 break;
 581                         cp = strchr(cp, '.') + 1;    /* we know there is one */
 582                         *pp++ = cp;
 583                         dots--;
 584                 }
 585                 *pp = NULL;
 586 #ifdef DEBUG
 587                 if (statp->options & RES_DEBUG) {
 588                         printf(";; res_init()... default dnsrch list:\n");
 589                         for (pp = statp->dnsrch; *pp; pp++)
 590                                 printf(";;\t%s\n", *pp);
 591                         printf(";;\t..END..\n");
 592                 }
 593 #endif
 594         }
 595
 596         if ((cp = getenv("RES_OPTIONS")) != NULL)
 597                 res_setoptions(statp, cp, "env");
 598         if (nserv > 0) {
 599                 statp->nscount = nserv;
 600                 statp->options |= RES_INIT;
 601         }
 602         return (0);
 603 }
 604
 605 static void
 606 res_setoptions(res_state statp, const char *options, const char *source)
 607 {
 608         const char *cp = options;
 609         int i;
 610         struct __res_state_ext *ext = statp->_u._ext.ext;
 611
 612 #ifdef DEBUG
 613         if (statp->options & RES_DEBUG)
 614                 printf(";; res_setoptions(\"%s\", \"%s\")...\n",
 615                        options, source);
 616 #endif
 617         while (*cp) {
 618                 /* skip leading and inner runs of spaces */
 619                 while (*cp == ' ' || *cp == '\t')
 620                         cp++;
 621                 /* search for and process individual options */
 622                 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
 623                         i = atoi(cp + sizeof("ndots:") - 1);
 624                         if (i <= RES_MAXNDOTS)
 625                                 statp->ndots = i;
 626                         else
 627                                 statp->ndots = RES_MAXNDOTS;
 628 #ifdef DEBUG
 629                         if (statp->options & RES_DEBUG)
 630                                 printf(";;\tndots=%d\n", statp->ndots);
 631 #endif
 632                 } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
 633                         i = atoi(cp + sizeof("timeout:") - 1);
 634                         if (i <= RES_MAXRETRANS)
 635                                 statp->retrans = i;
 636                         else
 637                                 statp->retrans = RES_MAXRETRANS;
 638 #ifdef DEBUG
 639                         if (statp->options & RES_DEBUG)
 640                                 printf(";;\ttimeout=%d\n", statp->retrans);
 641 #endif
 642                 } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
 643                         i = atoi(cp + sizeof("attempts:") - 1);
 644                         if (i <= RES_MAXRETRY)
 645                                 statp->retry = i;
 646                         else
 647                                 statp->retry = RES_MAXRETRY;
 648 #ifdef DEBUG
 649                         if (statp->options & RES_DEBUG)
 650                                 printf(";;\tattempts=%d\n", statp->retry);
 651 #endif
 652                 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
 653 #ifdef DEBUG
 654                         if (!(statp->options & RES_DEBUG)) {
 655                                 printf(";; res_setoptions(\"%s\", \"%s\")..\n",
 656                                        options, source);
 657                                 statp->options |= RES_DEBUG;
 658                         }
 659                         printf(";;\tdebug\n");
 660 #endif
 661                 } else if (!strncmp(cp, "no_tld_query",
 662                                     sizeof("no_tld_query") - 1) ||
 663                            !strncmp(cp, "no-tld-query",
 664                                     sizeof("no-tld-query") - 1)) {
 665                         statp->options |= RES_NOTLDQUERY;
 666                 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
 667                         statp->options |= RES_USE_INET6;
 668                 } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
 669                         statp->options |= RES_ROTATE;
 670                 } else if (!strncmp(cp, "no-check-names",
 671                                     sizeof("no-check-names") - 1)) {
 672                         statp->options |= RES_NOCHECKNAME;
 673                 }
 674 #ifdef RES_USE_EDNS0
 675                 else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
 676                         statp->options |= RES_USE_EDNS0;
 677                 }
 678 #endif
 679                 else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
 680                         statp->options |= RES_USE_DNAME;
 681                 }
 682                 else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
 683                         if (ext == NULL)
 684                                 goto skip;
 685                         cp += sizeof("nibble:") - 1;
 686                         i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
 687                         strncpy(ext->nsuffix, cp, (size_t)i);
 688                         ext->nsuffix[i] = '\0';
 689                 }
 690                 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
 691                         if (ext == NULL)
 692                                 goto skip;
 693                         cp += sizeof("nibble2:") - 1;
 694                         i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
 695                         strncpy(ext->nsuffix2, cp, (size_t)i);
 696                         ext->nsuffix2[i] = '\0';
 697                 }
 698                 else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
 699                         cp += sizeof("v6revmode:") - 1;
 700                         /* "nibble" and "bitstring" used to be valid */
 701                         if (!strncmp(cp, "single", sizeof("single") - 1)) {
 702                                 statp->options |= RES_NO_NIBBLE2;
 703                         } else if (!strncmp(cp, "both", sizeof("both") - 1)) {
 704                                 statp->options &=
 705                                          ~RES_NO_NIBBLE2;
 706                         }
 707                 }
 708                 else {
 709                         /* XXX - print a warning here? */
 710                 }
 711    skip:
 712                 /* skip to next run of spaces */
 713                 while (*cp && *cp != ' ' && *cp != '\t')
 714                         cp++;
 715         }
 716 }
 717
 718 /* XXX - should really support CIDR which means explicit masks always. */
 719 static u_int32_t
 720 net_mask(in)            /* XXX - should really use system's version of this */
 721         struct in_addr in;
 722 {
 723         register u_int32_t i = ntohl(in.s_addr);
 724
 725         if (IN_CLASSA(i))
 726                 return (htonl(IN_CLASSA_NET));
 727         else if (IN_CLASSB(i))
 728                 return (htonl(IN_CLASSB_NET));
 729         return (htonl(IN_CLASSC_NET));
 730 }
 731
 732 u_int
 733 res_randomid(void) {
 734         struct timeval now;
 735
 736         gettimeofday(&now, NULL);
 737         return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid()));
 738 }
 739
 740 /*
 741  * This routine is for closing the socket if a virtual circuit is used and
 742  * the program wants to close it.  This provides support for endhostent()
 743  * which expects to close the socket.
 744  *
 745  * This routine is not expected to be user visible.
 746  */
 747 void
 748 res_nclose(res_state statp) {
 749         int ns;
 750
 751         if (statp->_vcsock >= 0) {
 752                 (void) close(statp->_vcsock);
 753                 statp->_vcsock = -1;
 754                 statp->_flags &= ~(RES_F_VC | RES_F_CONN);
 755         }
 756         for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
 757                 if (statp->_u._ext.nssocks[ns] != -1) {
 758                         (void) close(statp->_u._ext.nssocks[ns]);
 759                         statp->_u._ext.nssocks[ns] = -1;
 760                 }
 761         }
 762 }
 763
 764 void
 765 res_ndestroy(res_state statp) {
 766         res_nclose(statp);
 767         if (statp->_u._ext.ext != NULL)
 768                 free(statp->_u._ext.ext);
 769         statp->options &= ~RES_INIT;
 770         statp->_u._ext.ext = NULL;
 771 }
 772
 773 const char *
 774 res_get_nibblesuffix(res_state statp) {
 775         if (statp->_u._ext.ext)
 776                 return (statp->_u._ext.ext->nsuffix);
 777         return ("ip6.arpa");
 778 }
 779
 780 const char *
 781 res_get_nibblesuffix2(res_state statp) {
 782         if (statp->_u._ext.ext)
 783                 return (statp->_u._ext.ext->nsuffix2);
 784         return ("ip6.int");
 785 }
 786
 787 void
 788 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {
 789         int i, nserv;
 790         size_t size;
 791
 792         /* close open servers */
 793         res_nclose(statp);
 794
 795         /* cause rtt times to be forgotten */
 796         statp->_u._ext.nscount = 0;
 797
 798         nserv = 0;
 799         for (i = 0; i < cnt && nserv < MAXNS; i++) {
 800                 switch (set->sin.sin_family) {
 801                 case AF_INET:
 802                         size = sizeof(set->sin);
 803                         if (statp->_u._ext.ext)
 804                                 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 805                                         &set->sin, size);
 806                         if (size <= sizeof(statp->nsaddr_list[nserv]))
 807                                 memcpy(&statp->nsaddr_list[nserv],
 808                                         &set->sin, size);
 809 #ifdef notdef
 810                         else
 811                                 statp->nsaddr_list[nserv].sin_family = 0;
 812 #endif
 813                         nserv++;
 814                         break;
 815
 816 #ifdef HAS_INET6_STRUCTS
 817                 case AF_INET6:
 818                         size = sizeof(set->sin6);
 819                         if (statp->_u._ext.ext)
 820                                 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
 821                                         &set->sin6, size);
 822                         if (size <= sizeof(statp->nsaddr_list[nserv]))
 823                                 memcpy(&statp->nsaddr_list[nserv],
 824                                         &set->sin6, size);
 825                         else
 826                                 statp->nsaddr_list[nserv].sin_family = 0;
 827                         nserv++;
 828                         break;
 829 #endif
 830
 831                 default:
 832                         break;
 833                 }
 834                 set++;
 835         }
 836         statp->nscount = nserv;
 837
 838 }
 839
 840 int
 841 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {
 842         int i;
 843         size_t size;
 844         u_int16_t family;
 845
 846         for (i = 0; i < statp->nscount && i < cnt; i++) {
 847                 if (statp->_u._ext.ext)
 848                         family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
 849                 else
 850                         family = statp->nsaddr_list[i].sin_family;
 851
 852                 switch (family) {
 853                 case AF_INET:
 854                         size = sizeof(set->sin);
 855                         if (statp->_u._ext.ext)
 856                                 memcpy(&set->sin,
 857                                        &statp->_u._ext.ext->nsaddrs[i],
 858                                        size);
 859                         else
 860                                 memcpy(&set->sin, &statp->nsaddr_list[i],
 861                                        size);
 862                         break;
 863
 864 #ifdef HAS_INET6_STRUCTS
 865                 case AF_INET6:
 866                         size = sizeof(set->sin6);
 867                         if (statp->_u._ext.ext)
 868                                 memcpy(&set->sin6,
 869                                        &statp->_u._ext.ext->nsaddrs[i],
 870                                        size);
 871                         else
 872                                 memcpy(&set->sin6, &statp->nsaddr_list[i],
 873                                        size);
 874                         break;
 875 #endif
 876
 877                 default:
 878                         set->sin.sin_family = 0;
 879                         break;
 880                 }
 881                 set++;
 882         }
 883         return (statp->nscount);
 884 }
 885
 886 #ifdef ANDROID_CHANGES
 887 static int _get_dns_change_count()
 888 {
 889         if (dns_change_prop == NULL) {
 890                 dns_change_prop = __system_property_find(DNS_CHANGE_PROP_NAME);
 891         }
 892         if (dns_change_prop != NULL) {
 893                 char propvalue[PROP_VALUE_MAX];
 894                 if (__system_property_read(dns_change_prop, NULL, propvalue) >= 1) {
 895                         return atoi(propvalue);
 896                 }
 897         }
 898         return -1;
 899 }
 900
 901 int res_get_dns_changed()
 902 {
 903         int change_count;
 904
 905         change_count = _get_dns_change_count();
 906         if (change_count != dns_last_change_counter) {
 907                 if (change_count != -1) {
 908                         dns_last_change_counter = change_count;
 909                 }
 910                 return 1;
 911         } else {
 912                 return 0;
 913         }
 914 }
 915 #endif /* ANDROID_CHANGES */