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 <errno.h> 103 #include <fcntl.h> 104 #include <sys/system_properties.h> 105 #endif /* ANDROID_CHANGES */ 106 107 #ifndef MIN 108 #define MIN(x,y) ((x)<(y)?(x):(y)) 109 #endif 110 111 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */ 112 #ifdef ANDROID_CHANGES 113 #include "resolv_private.h" 114 #define MAX_DNS_PROPERTIES 8 115 #define DNS_PROP_NAME_PREFIX "net.dns" 116 #define DNS_CHANGE_PROP_NAME "net.dnschange" 117 #define DNS_SEARCH_PROP_NAME "net.dns.search" 118 static const prop_info *dns_change_prop; 119 static int dns_last_change_counter; 120 static int _get_dns_change_count(); 121 #else 122 #include <resolv.h> 123 #endif 124 125 #include "res_private.h" 126 127 /* Options. Should all be left alone. */ 128 #ifndef DEBUG 129 #define DEBUG 130 #endif 131 132 static void res_setoptions __P((res_state, const char *, const char *)); 133 134 static const char sort_mask[] = "/&"; 135 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL) 136 static u_int32_t net_mask __P((struct in_addr)); 137 138 #if !defined(isascii) /* XXX - could be a function */ 139 # define isascii(c) (!(c & 0200)) 140 #endif 141 142 /* 143 * Resolver state default settings. 144 */ 145 146 /* 147 * Set up default settings. If the configuration file exist, the values 148 * there will have precedence. Otherwise, the server address is set to 149 * INADDR_ANY and the default domain name comes from the gethostname(). 150 * 151 * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1 152 * rather than INADDR_ANY ("0.0.0.0") as the default name server address 153 * since it was noted that INADDR_ANY actually meant ``the first interface 154 * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface, 155 * it had to be "up" in order for you to reach your own name server. It 156 * was later decided that since the recommended practice is to always 157 * install local static routes through 127.0.0.1 for all your network 158 * interfaces, that we could solve this problem without a code change. 159 * 160 * The configuration file should always be used, since it is the only way 161 * to specify a default domain. If you are running a server on your local 162 * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1" 163 * in the configuration file. 164 * 165 * Return 0 if completes successfully, -1 on error 166 */ 167 int 168 res_ninit(res_state statp) { 169 extern int __res_vinit(res_state, int); 170 171 return (__res_vinit(statp, 0)); 172 } 173 174 #ifdef ANDROID_CHANGES 175 static int load_domain_search_list(res_state statp) { 176 char propvalue[PROP_VALUE_MAX]; 177 register char *cp, **pp; 178 179 if(__system_property_get(DNS_SEARCH_PROP_NAME, propvalue) >= 1) { 180 strlcpy(statp->defdname, propvalue, sizeof(statp->defdname)); 181 if ((cp = strchr(statp->defdname, '\n')) != NULL) 182 *cp = '\0'; 183 cp = statp->defdname; 184 pp = statp->dnsrch; 185 while ( pp < statp->dnsrch + MAXDNSRCH ) { 186 while (*cp == ' ' || *cp == '\t') /* skip leading white space */ 187 cp++; 188 if (*cp == '\0') /* stop if nothing more */ 189 break; 190 *pp++ = cp; /* record this search domain */ 191 while (*cp) { /* zero-terminate it */ 192 if (*cp == ' ' || *cp == '\t') { 193 *cp++ = '\0'; 194 break; 195 } 196 cp++; 197 } 198 } 199 *pp = NULL; /* statp->dnsrch has MAXDNSRCH+1 items */ 200 if (pp > statp->dnsrch) 201 return 1; 202 } 203 statp->defdname[0] = '\0'; /* no default domain name on Android */ 204 statp->dnsrch[0] = NULL; 205 return 0; 206 } 207 #endif 208 209 /* This function has to be reachable by res_data.c but not publicly. */ 210 int 211 __res_vinit(res_state statp, int preinit) { 212 register FILE *fp; 213 register char *cp, **pp; 214 register int n; 215 char buf[BUFSIZ]; 216 int nserv = 0; /* number of nameserver records read from file */ 217 int haveenv = 0; 218 int havesearch = 0; 219 int nsort = 0; 220 char *net; 221 int dots; 222 union res_sockaddr_union u[2]; 223 #ifdef ANDROID_CHANGES 224 pid_t mypid = getpid(); 225 int use_proc_props = 0; 226 int found_prop; 227 char dnsProperty[PROP_VALUE_MAX]; 228 #endif 229 230 if ((statp->options & RES_INIT) != 0U) 231 res_ndestroy(statp); 232 233 if (!preinit) { 234 statp->retrans = RES_TIMEOUT; 235 statp->retry = RES_DFLRETRY; 236 statp->options = RES_DEFAULT; 237 statp->id = res_randomid(); 238 } 239 240 memset(u, 0, sizeof(u)); 241 #ifdef USELOOPBACK 242 u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1); 243 #else 244 u[nserv].sin.sin_addr.s_addr = INADDR_ANY; 245 #endif 246 u[nserv].sin.sin_family = AF_INET; 247 u[nserv].sin.sin_port = htons(NAMESERVER_PORT); 248 #ifdef HAVE_SA_LEN 249 u[nserv].sin.sin_len = sizeof(struct sockaddr_in); 250 #endif 251 nserv++; 252 #ifdef HAS_INET6_STRUCTS 253 #ifdef USELOOPBACK 254 u[nserv].sin6.sin6_addr = in6addr_loopback; 255 #else 256 u[nserv].sin6.sin6_addr = in6addr_any; 257 #endif 258 u[nserv].sin6.sin6_family = AF_INET6; 259 u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT); 260 #ifdef HAVE_SA_LEN 261 u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6); 262 #endif 263 nserv++; 264 #endif 265 statp->nscount = 0; 266 statp->ndots = 1; 267 statp->pfcode = 0; 268 statp->_vcsock = -1; 269 statp->_flags = 0; 270 statp->qhook = NULL; 271 statp->rhook = NULL; 272 statp->_u._ext.nscount = 0; 273 statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext)); 274 if (statp->_u._ext.ext != NULL) { 275 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext)); 276 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr; 277 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa"); 278 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int"); 279 } 280 statp->nsort = 0; 281 res_setservers(statp, u, nserv); 282 283 #if 0 /* IGNORE THE ENVIRONMENT */ 284 /* Allow user to override the local domain definition */ 285 if ((cp = getenv("LOCALDOMAIN")) != NULL) { 286 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 287 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 288 haveenv++; 289 290 /* 291 * Set search list to be blank-separated strings 292 * from rest of env value. Permits users of LOCALDOMAIN 293 * to still have a search list, and anyone to set the 294 * one that they want to use as an individual (even more 295 * important now that the rfc1535 stuff restricts searches) 296 */ 297 cp = statp->defdname; 298 pp = statp->dnsrch; 299 *pp++ = cp; 300 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) { 301 if (*cp == '\n') /* silly backwards compat */ 302 break; 303 else if (*cp == ' ' || *cp == '\t') { 304 *cp = 0; 305 n = 1; 306 } else if (n) { 307 *pp++ = cp; 308 n = 0; 309 havesearch = 1; 310 } 311 } 312 /* null terminate last domain if there are excess */ 313 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n') 314 cp++; 315 *cp = '\0'; 316 *pp++ = 0; 317 } 318 if (nserv > 0) 319 statp->nscount = nserv; 320 #endif 321 #ifdef ANDROID_CHANGES /* READ FROM SYSTEM PROPERTIES */ 322 dns_last_change_counter = _get_dns_change_count(); 323 324 nserv = 0; 325 for(n = 1; n <= MAX_DNS_PROPERTIES && nserv < MAXNS; n++) { 326 char propname[PROP_NAME_MAX]; 327 char propvalue[PROP_VALUE_MAX]; 328 329 struct addrinfo hints, *ai; 330 char sbuf[NI_MAXSERV]; 331 const size_t minsiz = sizeof(statp->_u._ext.ext->nsaddrs[0]); 332 333 /* 334 * Check first for process-specific properties, and if those don't 335 * exist, try the generic properties. 336 */ 337 found_prop = 0; 338 if (n == 1 || use_proc_props) { 339 snprintf(propname, sizeof(propname), "%s%d.%d", DNS_PROP_NAME_PREFIX, n, mypid); 340 if(__system_property_get(propname, propvalue) < 1) { 341 if (use_proc_props) { 342 break; 343 } 344 } else { 345 found_prop = 1; 346 use_proc_props = 1; 347 } 348 } 349 if (!found_prop) { 350 snprintf(propname, sizeof(propname), "%s%d", DNS_PROP_NAME_PREFIX, n); 351 if(__system_property_get(propname, propvalue) < 1) { 352 break; 353 } 354 } 355 356 cp = propvalue; 357 358 while (*cp == ' ' || *cp == '\t') 359 cp++; 360 cp[strcspn(cp, ";# \t\n")] = '\0'; 361 if ((*cp != '\0') && (*cp != '\n')) { 362 memset(&hints, 0, sizeof(hints)); 363 hints.ai_family = PF_UNSPEC; 364 hints.ai_socktype = SOCK_DGRAM; /*dummy*/ 365 hints.ai_flags = AI_NUMERICHOST; 366 sprintf(sbuf, "%u", NAMESERVER_PORT); 367 if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 && 368 (size_t)ai->ai_addrlen <= minsiz) { 369 if (statp->_u._ext.ext != NULL) { 370 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 371 ai->ai_addr, ai->ai_addrlen); 372 } 373 if ((size_t)ai->ai_addrlen <= 374 sizeof(statp->nsaddr_list[nserv])) { 375 memcpy(&statp->nsaddr_list[nserv], 376 ai->ai_addr, ai->ai_addrlen); 377 } else { 378 statp->nsaddr_list[nserv].sin_family = 0; 379 } 380 freeaddrinfo(ai); 381 nserv++; 382 } 383 } 384 } 385 386 /* Add the domain search list */ 387 havesearch = load_domain_search_list(statp); 388 #else /* !ANDROID_CHANGES - IGNORE resolv.conf in Android */ 389 #define MATCH(line, name) \ 390 (!strncmp(line, name, sizeof(name) - 1) && \ 391 (line[sizeof(name) - 1] == ' ' || \ 392 line[sizeof(name) - 1] == '\t')) 393 394 nserv = 0; 395 if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) { 396 /* read the config file */ 397 while (fgets(buf, sizeof(buf), fp) != NULL) { 398 /* skip comments */ 399 if (*buf == ';' || *buf == '#') 400 continue; 401 /* read default domain name */ 402 if (MATCH(buf, "domain")) { 403 if (haveenv) /* skip if have from environ */ 404 continue; 405 cp = buf + sizeof("domain") - 1; 406 while (*cp == ' ' || *cp == '\t') 407 cp++; 408 if ((*cp == '\0') || (*cp == '\n')) 409 continue; 410 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 411 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 412 if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL) 413 *cp = '\0'; 414 havesearch = 0; 415 continue; 416 } 417 /* set search list */ 418 if (MATCH(buf, "search")) { 419 if (haveenv) /* skip if have from environ */ 420 continue; 421 cp = buf + sizeof("search") - 1; 422 while (*cp == ' ' || *cp == '\t') 423 cp++; 424 if ((*cp == '\0') || (*cp == '\n')) 425 continue; 426 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 427 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 428 if ((cp = strchr(statp->defdname, '\n')) != NULL) 429 *cp = '\0'; 430 /* 431 * Set search list to be blank-separated strings 432 * on rest of line. 433 */ 434 cp = statp->defdname; 435 pp = statp->dnsrch; 436 *pp++ = cp; 437 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) { 438 if (*cp == ' ' || *cp == '\t') { 439 *cp = 0; 440 n = 1; 441 } else if (n) { 442 *pp++ = cp; 443 n = 0; 444 } 445 } 446 /* null terminate last domain if there are excess */ 447 while (*cp != '\0' && *cp != ' ' && *cp != '\t') 448 cp++; 449 *cp = '\0'; 450 *pp++ = 0; 451 havesearch = 1; 452 continue; 453 } 454 /* read nameservers to query */ 455 if (MATCH(buf, "nameserver") && nserv < MAXNS) { 456 struct addrinfo hints, *ai; 457 char sbuf[NI_MAXSERV]; 458 const size_t minsiz = 459 sizeof(statp->_u._ext.ext->nsaddrs[0]); 460 461 cp = buf + sizeof("nameserver") - 1; 462 while (*cp == ' ' || *cp == '\t') 463 cp++; 464 cp[strcspn(cp, ";# \t\n")] = '\0'; 465 if ((*cp != '\0') && (*cp != '\n')) { 466 memset(&hints, 0, sizeof(hints)); 467 hints.ai_family = PF_UNSPEC; 468 hints.ai_socktype = SOCK_DGRAM; /*dummy*/ 469 hints.ai_flags = AI_NUMERICHOST; 470 sprintf(sbuf, "%u", NAMESERVER_PORT); 471 if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 && 472 ai->ai_addrlen <= minsiz) { 473 if (statp->_u._ext.ext != NULL) { 474 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 475 ai->ai_addr, ai->ai_addrlen); 476 } 477 if (ai->ai_addrlen <= 478 sizeof(statp->nsaddr_list[nserv])) { 479 memcpy(&statp->nsaddr_list[nserv], 480 ai->ai_addr, ai->ai_addrlen); 481 } else 482 statp->nsaddr_list[nserv].sin_family = 0; 483 freeaddrinfo(ai); 484 nserv++; 485 } 486 } 487 continue; 488 } 489 if (MATCH(buf, "sortlist")) { 490 struct in_addr a; 491 492 cp = buf + sizeof("sortlist") - 1; 493 while (nsort < MAXRESOLVSORT) { 494 while (*cp == ' ' || *cp == '\t') 495 cp++; 496 if (*cp == '\0' || *cp == '\n' || *cp == ';') 497 break; 498 net = cp; 499 while (*cp && !ISSORTMASK(*cp) && *cp != ';' && 500 isascii(*cp) && !isspace((unsigned char)*cp)) 501 cp++; 502 n = *cp; 503 *cp = 0; 504 if (inet_aton(net, &a)) { 505 statp->sort_list[nsort].addr = a; 506 if (ISSORTMASK(n)) { 507 *cp++ = n; 508 net = cp; 509 while (*cp && *cp != ';' && 510 isascii(*cp) && 511 !isspace((unsigned char)*cp)) 512 cp++; 513 n = *cp; 514 *cp = 0; 515 if (inet_aton(net, &a)) { 516 statp->sort_list[nsort].mask = a.s_addr; 517 } else { 518 statp->sort_list[nsort].mask = 519 net_mask(statp->sort_list[nsort].addr); 520 } 521 } else { 522 statp->sort_list[nsort].mask = 523 net_mask(statp->sort_list[nsort].addr); 524 } 525 nsort++; 526 } 527 *cp = n; 528 } 529 continue; 530 } 531 if (MATCH(buf, "options")) { 532 res_setoptions(statp, buf + sizeof("options") - 1, "conf"); 533 continue; 534 } 535 } 536 if (nserv > 0) 537 statp->nscount = nserv; 538 statp->nsort = nsort; 539 (void) fclose(fp); 540 } 541 #endif /* !ANDROID_CHANGES */ 542 /* 543 * Last chance to get a nameserver. This should not normally 544 * be necessary 545 */ 546 #ifdef NO_RESOLV_CONF 547 if(nserv == 0) 548 nserv = get_nameservers(statp); 549 #endif 550 551 if (statp->defdname[0] == 0 && 552 gethostname(buf, sizeof(statp->defdname) - 1) == 0 && 553 (cp = strchr(buf, '.')) != NULL) 554 strcpy(statp->defdname, cp + 1); 555 556 /* find components of local domain that might be searched */ 557 if (havesearch == 0) { 558 pp = statp->dnsrch; 559 *pp++ = statp->defdname; 560 *pp = NULL; 561 562 dots = 0; 563 for (cp = statp->defdname; *cp; cp++) 564 dots += (*cp == '.'); 565 566 cp = statp->defdname; 567 while (pp < statp->dnsrch + MAXDFLSRCH) { 568 if (dots < LOCALDOMAINPARTS) 569 break; 570 cp = strchr(cp, '.') + 1; /* we know there is one */ 571 *pp++ = cp; 572 dots--; 573 } 574 *pp = NULL; 575 #ifdef DEBUG 576 if (statp->options & RES_DEBUG) { 577 printf(";; res_init()... default dnsrch list:\n"); 578 for (pp = statp->dnsrch; *pp; pp++) 579 printf(";;\t%s\n", *pp); 580 printf(";;\t..END..\n"); 581 } 582 #endif 583 } 584 585 if ((cp = getenv("RES_OPTIONS")) != NULL) 586 res_setoptions(statp, cp, "env"); 587 if (nserv > 0) { 588 statp->nscount = nserv; 589 statp->options |= RES_INIT; 590 } 591 return (0); 592 } 593 594 static void 595 res_setoptions(res_state statp, const char *options, const char *source) 596 { 597 const char *cp = options; 598 int i; 599 struct __res_state_ext *ext = statp->_u._ext.ext; 600 601 #ifdef DEBUG 602 if (statp->options & RES_DEBUG) 603 printf(";; res_setoptions(\"%s\", \"%s\")...\n", 604 options, source); 605 #endif 606 while (*cp) { 607 /* skip leading and inner runs of spaces */ 608 while (*cp == ' ' || *cp == '\t') 609 cp++; 610 /* search for and process individual options */ 611 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) { 612 i = atoi(cp + sizeof("ndots:") - 1); 613 if (i <= RES_MAXNDOTS) 614 statp->ndots = i; 615 else 616 statp->ndots = RES_MAXNDOTS; 617 #ifdef DEBUG 618 if (statp->options & RES_DEBUG) 619 printf(";;\tndots=%d\n", statp->ndots); 620 #endif 621 } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) { 622 i = atoi(cp + sizeof("timeout:") - 1); 623 if (i <= RES_MAXRETRANS) 624 statp->retrans = i; 625 else 626 statp->retrans = RES_MAXRETRANS; 627 #ifdef DEBUG 628 if (statp->options & RES_DEBUG) 629 printf(";;\ttimeout=%d\n", statp->retrans); 630 #endif 631 } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){ 632 i = atoi(cp + sizeof("attempts:") - 1); 633 if (i <= RES_MAXRETRY) 634 statp->retry = i; 635 else 636 statp->retry = RES_MAXRETRY; 637 #ifdef DEBUG 638 if (statp->options & RES_DEBUG) 639 printf(";;\tattempts=%d\n", statp->retry); 640 #endif 641 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) { 642 #ifdef DEBUG 643 if (!(statp->options & RES_DEBUG)) { 644 printf(";; res_setoptions(\"%s\", \"%s\")..\n", 645 options, source); 646 statp->options |= RES_DEBUG; 647 } 648 printf(";;\tdebug\n"); 649 #endif 650 } else if (!strncmp(cp, "no_tld_query", 651 sizeof("no_tld_query") - 1) || 652 !strncmp(cp, "no-tld-query", 653 sizeof("no-tld-query") - 1)) { 654 statp->options |= RES_NOTLDQUERY; 655 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) { 656 statp->options |= RES_USE_INET6; 657 } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) { 658 statp->options |= RES_ROTATE; 659 } else if (!strncmp(cp, "no-check-names", 660 sizeof("no-check-names") - 1)) { 661 statp->options |= RES_NOCHECKNAME; 662 } 663 #ifdef RES_USE_EDNS0 664 else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) { 665 statp->options |= RES_USE_EDNS0; 666 } 667 #endif 668 else if (!strncmp(cp, "dname", sizeof("dname") - 1)) { 669 statp->options |= RES_USE_DNAME; 670 } 671 else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) { 672 if (ext == NULL) 673 goto skip; 674 cp += sizeof("nibble:") - 1; 675 i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1); 676 strncpy(ext->nsuffix, cp, (size_t)i); 677 ext->nsuffix[i] = '\0'; 678 } 679 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) { 680 if (ext == NULL) 681 goto skip; 682 cp += sizeof("nibble2:") - 1; 683 i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1); 684 strncpy(ext->nsuffix2, cp, (size_t)i); 685 ext->nsuffix2[i] = '\0'; 686 } 687 else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) { 688 cp += sizeof("v6revmode:") - 1; 689 /* "nibble" and "bitstring" used to be valid */ 690 if (!strncmp(cp, "single", sizeof("single") - 1)) { 691 statp->options |= RES_NO_NIBBLE2; 692 } else if (!strncmp(cp, "both", sizeof("both") - 1)) { 693 statp->options &= 694 ~RES_NO_NIBBLE2; 695 } 696 } 697 else { 698 /* XXX - print a warning here? */ 699 } 700 skip: 701 /* skip to next run of spaces */ 702 while (*cp && *cp != ' ' && *cp != '\t') 703 cp++; 704 } 705 } 706 707 /* XXX - should really support CIDR which means explicit masks always. */ 708 static u_int32_t 709 net_mask(in) /* XXX - should really use system's version of this */ 710 struct in_addr in; 711 { 712 register u_int32_t i = ntohl(in.s_addr); 713 714 if (IN_CLASSA(i)) 715 return (htonl(IN_CLASSA_NET)); 716 else if (IN_CLASSB(i)) 717 return (htonl(IN_CLASSB_NET)); 718 return (htonl(IN_CLASSC_NET)); 719 } 720 721 #ifdef ANDROID_CHANGES 722 static int 723 real_randomid(u_int *random_value) { 724 /* open the nonblocking random device, returning -1 on failure */ 725 int random_device = open("/dev/urandom", O_RDONLY); 726 if (random_device < 0) { 727 return -1; 728 } 729 730 /* read from the random device, returning -1 on failure (or too many retries)*/ 731 u_int retry = 5; 732 for (retry; retry > 0; retry--) { 733 int retval = read(random_device, random_value, sizeof(u_int)); 734 if (retval == sizeof(u_int)) { 735 *random_value &= 0xffff; 736 close(random_device); 737 return 0; 738 } else if ((retval < 0) && (errno != EINTR)) { 739 break; 740 } 741 } 742 743 close(random_device); 744 return -1; 745 } 746 #endif /* ANDROID_CHANGES */ 747 748 u_int 749 res_randomid(void) { 750 #ifdef ANDROID_CHANGES 751 int status = 0; 752 u_int output = 0; 753 status = real_randomid(&output); 754 if (status != -1) { 755 return output; 756 } 757 #endif /* ANDROID_CHANGES */ 758 struct timeval now; 759 gettimeofday(&now, NULL); 760 return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid())); 761 } 762 763 /* 764 * This routine is for closing the socket if a virtual circuit is used and 765 * the program wants to close it. This provides support for endhostent() 766 * which expects to close the socket. 767 * 768 * This routine is not expected to be user visible. 769 */ 770 void 771 res_nclose(res_state statp) { 772 int ns; 773 774 if (statp->_vcsock >= 0) { 775 (void) close(statp->_vcsock); 776 statp->_vcsock = -1; 777 statp->_flags &= ~(RES_F_VC | RES_F_CONN); 778 } 779 for (ns = 0; ns < statp->_u._ext.nscount; ns++) { 780 if (statp->_u._ext.nssocks[ns] != -1) { 781 (void) close(statp->_u._ext.nssocks[ns]); 782 statp->_u._ext.nssocks[ns] = -1; 783 } 784 } 785 } 786 787 void 788 res_ndestroy(res_state statp) { 789 res_nclose(statp); 790 if (statp->_u._ext.ext != NULL) 791 free(statp->_u._ext.ext); 792 statp->options &= ~RES_INIT; 793 statp->_u._ext.ext = NULL; 794 } 795 796 const char * 797 res_get_nibblesuffix(res_state statp) { 798 if (statp->_u._ext.ext) 799 return (statp->_u._ext.ext->nsuffix); 800 return ("ip6.arpa"); 801 } 802 803 const char * 804 res_get_nibblesuffix2(res_state statp) { 805 if (statp->_u._ext.ext) 806 return (statp->_u._ext.ext->nsuffix2); 807 return ("ip6.int"); 808 } 809 810 void 811 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) { 812 int i, nserv; 813 size_t size; 814 815 /* close open servers */ 816 res_nclose(statp); 817 818 /* cause rtt times to be forgotten */ 819 statp->_u._ext.nscount = 0; 820 821 nserv = 0; 822 for (i = 0; i < cnt && nserv < MAXNS; i++) { 823 switch (set->sin.sin_family) { 824 case AF_INET: 825 size = sizeof(set->sin); 826 if (statp->_u._ext.ext) 827 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 828 &set->sin, size); 829 if (size <= sizeof(statp->nsaddr_list[nserv])) 830 memcpy(&statp->nsaddr_list[nserv], 831 &set->sin, size); 832 #ifdef notdef 833 else 834 statp->nsaddr_list[nserv].sin_family = 0; 835 #endif 836 nserv++; 837 break; 838 839 #ifdef HAS_INET6_STRUCTS 840 case AF_INET6: 841 size = sizeof(set->sin6); 842 if (statp->_u._ext.ext) 843 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 844 &set->sin6, size); 845 if (size <= sizeof(statp->nsaddr_list[nserv])) 846 memcpy(&statp->nsaddr_list[nserv], 847 &set->sin6, size); 848 else 849 statp->nsaddr_list[nserv].sin_family = 0; 850 nserv++; 851 break; 852 #endif 853 854 default: 855 break; 856 } 857 set++; 858 } 859 statp->nscount = nserv; 860 861 } 862 863 int 864 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) { 865 int i; 866 size_t size; 867 u_int16_t family; 868 869 for (i = 0; i < statp->nscount && i < cnt; i++) { 870 if (statp->_u._ext.ext) 871 family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family; 872 else 873 family = statp->nsaddr_list[i].sin_family; 874 875 switch (family) { 876 case AF_INET: 877 size = sizeof(set->sin); 878 if (statp->_u._ext.ext) 879 memcpy(&set->sin, 880 &statp->_u._ext.ext->nsaddrs[i], 881 size); 882 else 883 memcpy(&set->sin, &statp->nsaddr_list[i], 884 size); 885 break; 886 887 #ifdef HAS_INET6_STRUCTS 888 case AF_INET6: 889 size = sizeof(set->sin6); 890 if (statp->_u._ext.ext) 891 memcpy(&set->sin6, 892 &statp->_u._ext.ext->nsaddrs[i], 893 size); 894 else 895 memcpy(&set->sin6, &statp->nsaddr_list[i], 896 size); 897 break; 898 #endif 899 900 default: 901 set->sin.sin_family = 0; 902 break; 903 } 904 set++; 905 } 906 return (statp->nscount); 907 } 908 909 #ifdef ANDROID_CHANGES 910 static int _get_dns_change_count() 911 { 912 if (dns_change_prop == NULL) { 913 dns_change_prop = __system_property_find(DNS_CHANGE_PROP_NAME); 914 } 915 if (dns_change_prop != NULL) { 916 char propvalue[PROP_VALUE_MAX]; 917 if (__system_property_read(dns_change_prop, NULL, propvalue) >= 1) { 918 return atoi(propvalue); 919 } 920 } 921 return -1; 922 } 923 924 int res_get_dns_changed() 925 { 926 int change_count; 927 928 change_count = _get_dns_change_count(); 929 if (change_count != dns_last_change_counter) { 930 if (change_count != -1) { 931 dns_last_change_counter = change_count; 932 } 933 return 1; 934 } else { 935 return 0; 936 } 937 } 938 #endif /* ANDROID_CHANGES */ 939
