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