res_init.c revision 331722
1/* 2 * Copyright (c) 1985, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30/* 31 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 32 * 33 * Permission to use, copy, modify, and distribute this software for any 34 * purpose with or without fee is hereby granted, provided that the above 35 * copyright notice and this permission notice appear in all copies, and that 36 * the name of Digital Equipment Corporation not be used in advertising or 37 * publicity pertaining to distribution of the document or software without 38 * specific, written prior permission. 39 * 40 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 41 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 42 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 43 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 44 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 45 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 46 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 47 * SOFTWARE. 48 */ 49 50/* 51 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 52 * Portions Copyright (c) 1996-1999 by Internet Software Consortium. 53 * 54 * Permission to use, copy, modify, and distribute this software for any 55 * purpose with or without fee is hereby granted, provided that the above 56 * copyright notice and this permission notice appear in all copies. 57 * 58 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 59 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 60 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 61 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 62 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 63 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 64 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 65 */ 66 67#if defined(LIBC_SCCS) && !defined(lint) 68static const char sccsid[] = "@(#)res_init.c 8.1 (Berkeley) 6/7/93"; 69static const char rcsid[] = "$Id: res_init.c,v 1.26 2008/12/11 09:59:00 marka Exp $"; 70#endif /* LIBC_SCCS and not lint */ 71#include <sys/cdefs.h> 72__FBSDID("$FreeBSD: stable/11/lib/libc/resolv/res_init.c 331722 2018-03-29 02:50:57Z eadler $"); 73 74#include "port_before.h" 75 76#include "namespace.h" 77 78#include <sys/param.h> 79#include <sys/socket.h> 80#include <sys/stat.h> 81#include <sys/time.h> 82 83#include <netinet/in.h> 84#include <arpa/inet.h> 85#include <arpa/nameser.h> 86 87#include <ctype.h> 88#include <stdio.h> 89#include <stdlib.h> 90#include <string.h> 91#include <unistd.h> 92#include <netdb.h> 93 94#ifndef HAVE_MD5 95# include "../dst/md5.h" 96#else 97# ifdef SOLARIS2 98# include <sys/md5.h> 99# elif _LIBC 100# include <md5.h> 101# endif 102#endif 103#ifndef _MD5_H_ 104# define _MD5_H_ 1 /*%< make sure we do not include rsaref md5.h file */ 105#endif 106 107#include "un-namespace.h" 108 109#include "port_after.h" 110 111/* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */ 112#include <resolv.h> 113 114#include "res_private.h" 115 116/*% Options. Should all be left alone. */ 117#define RESOLVSORT 118#ifndef DEBUG 119#define DEBUG 120#endif 121 122#ifdef SOLARIS2 123#include <sys/systeminfo.h> 124#endif 125 126static void res_setoptions(res_state, const char *, const char *); 127 128#ifdef RESOLVSORT 129static const char sort_mask[] = "/&"; 130#define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL) 131static u_int32_t net_mask(struct in_addr); 132#endif 133 134#if !defined(isascii) /*%< XXX - could be a function */ 135# define isascii(c) (!(c & 0200)) 136#endif 137 138/* 139 * Resolver state default settings. 140 */ 141 142/*% 143 * Set up default settings. If the configuration file exist, the values 144 * there will have precedence. Otherwise, the server address is set to 145 * INADDR_ANY and the default domain name comes from the gethostname(). 146 * 147 * An interim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1 148 * rather than INADDR_ANY ("0.0.0.0") as the default name server address 149 * since it was noted that INADDR_ANY actually meant ``the first interface 150 * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface, 151 * it had to be "up" in order for you to reach your own name server. It 152 * was later decided that since the recommended practice is to always 153 * install local static routes through 127.0.0.1 for all your network 154 * interfaces, that we could solve this problem without a code change. 155 * 156 * The configuration file should always be used, since it is the only way 157 * to specify a default domain. If you are running a server on your local 158 * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1" 159 * in the configuration file. 160 * 161 * Return 0 if completes successfully, -1 on error 162 */ 163int 164res_ninit(res_state statp) { 165 extern int __res_vinit(res_state, int); 166 167 return (__res_vinit(statp, 0)); 168} 169 170/*% This function has to be reachable by res_data.c but not publicly. */ 171int 172__res_vinit(res_state statp, int preinit) { 173 FILE *fp; 174 char *cp, **pp; 175 int n; 176 char buf[BUFSIZ]; 177 int nserv = 0; /*%< number of nameserver records read from file */ 178 int haveenv = 0; 179 int havesearch = 0; 180#ifdef RESOLVSORT 181 int nsort = 0; 182 char *net; 183#endif 184 int dots; 185 union res_sockaddr_union u[2]; 186 int maxns = MAXNS; 187 188 RES_SET_H_ERRNO(statp, 0); 189 if (statp->_u._ext.ext != NULL) 190 res_ndestroy(statp); 191 192 if (!preinit) { 193 statp->retrans = RES_TIMEOUT; 194 statp->retry = RES_DFLRETRY; 195 statp->options = RES_DEFAULT; 196 } 197 198 statp->_rnd = malloc(16); 199 res_rndinit(statp); 200 statp->id = res_nrandomid(statp); 201 202 memset(u, 0, sizeof(u)); 203#ifdef USELOOPBACK 204 u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1); 205#else 206 u[nserv].sin.sin_addr.s_addr = INADDR_ANY; 207#endif 208 u[nserv].sin.sin_family = AF_INET; 209 u[nserv].sin.sin_port = htons(NAMESERVER_PORT); 210#ifdef HAVE_SA_LEN 211 u[nserv].sin.sin_len = sizeof(struct sockaddr_in); 212#endif 213 nserv++; 214#ifdef HAS_INET6_STRUCTS 215#ifdef USELOOPBACK 216 u[nserv].sin6.sin6_addr = in6addr_loopback; 217#else 218 u[nserv].sin6.sin6_addr = in6addr_any; 219#endif 220 u[nserv].sin6.sin6_family = AF_INET6; 221 u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT); 222#ifdef HAVE_SA_LEN 223 u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6); 224#endif 225 nserv++; 226#endif 227 statp->nscount = 0; 228 statp->ndots = 1; 229 statp->pfcode = 0; 230 statp->_vcsock = -1; 231 statp->_flags = 0; 232 statp->qhook = NULL; 233 statp->rhook = NULL; 234 statp->_u._ext.nscount = 0; 235 statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext)); 236 if (statp->_u._ext.ext != NULL) { 237 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext)); 238 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr; 239 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa"); 240 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int"); 241 statp->_u._ext.ext->reload_period = 2; 242 } else { 243 /* 244 * Historically res_init() rarely, if at all, failed. 245 * Examples and applications exist which do not check 246 * our return code. Furthermore several applications 247 * simply call us to get the systems domainname. So 248 * rather then immediately fail here we store the 249 * failure, which is returned later, in h_errno. And 250 * prevent the collection of 'nameserver' information 251 * by setting maxns to 0. Thus applications that fail 252 * to check our return code wont be able to make 253 * queries anyhow. 254 */ 255 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 256 maxns = 0; 257 } 258#ifdef RESOLVSORT 259 statp->nsort = 0; 260#endif 261 res_setservers(statp, u, nserv); 262 263#ifdef SOLARIS2 264 /* 265 * The old libresolv derived the defaultdomain from NIS/NIS+. 266 * We want to keep this behaviour 267 */ 268 { 269 char buf[sizeof(statp->defdname)], *cp; 270 int ret; 271 272 if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 && 273 (unsigned int)ret <= sizeof(buf)) { 274 if (buf[0] == '+') 275 buf[0] = '.'; 276 cp = strchr(buf, '.'); 277 cp = (cp == NULL) ? buf : (cp + 1); 278 strncpy(statp->defdname, cp, 279 sizeof(statp->defdname) - 1); 280 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 281 } 282 } 283#endif /* SOLARIS2 */ 284 285 /* Allow user to override the local domain definition */ 286 if (issetugid() == 0 && (cp = getenv("LOCALDOMAIN")) != NULL) { 287 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 288 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 289 haveenv++; 290 291 /* 292 * Set search list to be blank-separated strings 293 * from rest of env value. Permits users of LOCALDOMAIN 294 * to still have a search list, and anyone to set the 295 * one that they want to use as an individual (even more 296 * important now that the rfc1535 stuff restricts searches) 297 */ 298 cp = statp->defdname; 299 pp = statp->dnsrch; 300 *pp++ = cp; 301 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) { 302 if (*cp == '\n') /*%< silly backwards compat */ 303 break; 304 else if (*cp == ' ' || *cp == '\t') { 305 *cp = 0; 306 n = 1; 307 } else if (n) { 308 *pp++ = cp; 309 n = 0; 310 havesearch = 1; 311 } 312 } 313 /* null terminate last domain if there are excess */ 314 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n') 315 cp++; 316 *cp = '\0'; 317 *pp++ = NULL; 318 } 319 320#define MATCH(line, name) \ 321 (!strncmp(line, name, sizeof(name) - 1) && \ 322 (line[sizeof(name) - 1] == ' ' || \ 323 line[sizeof(name) - 1] == '\t')) 324 325 nserv = 0; 326 if ((fp = fopen(_PATH_RESCONF, "re")) != NULL) { 327 struct stat sb; 328 struct timespec now; 329 330 if (statp->_u._ext.ext != NULL) { 331 if (_fstat(fileno(fp), &sb) == 0) { 332 statp->_u._ext.ext->conf_mtim = sb.st_mtim; 333 if (clock_gettime(CLOCK_MONOTONIC_FAST, &now) == 0) { 334 statp->_u._ext.ext->conf_stat = now.tv_sec; 335 } 336 } 337 } 338 339 /* read the config file */ 340 while (fgets(buf, sizeof(buf), fp) != NULL) { 341 /* skip comments */ 342 if (*buf == ';' || *buf == '#') 343 continue; 344 /* read default domain name */ 345 if (MATCH(buf, "domain")) { 346 if (haveenv) /*%< skip if have from environ */ 347 continue; 348 cp = buf + sizeof("domain") - 1; 349 while (*cp == ' ' || *cp == '\t') 350 cp++; 351 if ((*cp == '\0') || (*cp == '\n')) 352 continue; 353 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 354 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 355 if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL) 356 *cp = '\0'; 357 havesearch = 0; 358 continue; 359 } 360 /* set search list */ 361 if (MATCH(buf, "search")) { 362 if (haveenv) /*%< skip if have from environ */ 363 continue; 364 cp = buf + sizeof("search") - 1; 365 while (*cp == ' ' || *cp == '\t') 366 cp++; 367 if ((*cp == '\0') || (*cp == '\n')) 368 continue; 369 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 370 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 371 if ((cp = strchr(statp->defdname, '\n')) != NULL) 372 *cp = '\0'; 373 /* 374 * Set search list to be blank-separated strings 375 * on rest of line. 376 */ 377 cp = statp->defdname; 378 pp = statp->dnsrch; 379 *pp++ = cp; 380 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) { 381 if (*cp == ' ' || *cp == '\t') { 382 *cp = 0; 383 n = 1; 384 } else if (n) { 385 *pp++ = cp; 386 n = 0; 387 } 388 } 389 /* null terminate last domain if there are excess */ 390 while (*cp != '\0' && *cp != ' ' && *cp != '\t') 391 cp++; 392 *cp = '\0'; 393 *pp++ = NULL; 394 havesearch = 1; 395 continue; 396 } 397 /* read nameservers to query */ 398 if (MATCH(buf, "nameserver") && nserv < maxns) { 399 struct addrinfo hints, *ai; 400 char sbuf[NI_MAXSERV]; 401 const size_t minsiz = 402 sizeof(statp->_u._ext.ext->nsaddrs[0]); 403 404 cp = buf + sizeof("nameserver") - 1; 405 while (*cp == ' ' || *cp == '\t') 406 cp++; 407 cp[strcspn(cp, ";# \t\n")] = '\0'; 408 if ((*cp != '\0') && (*cp != '\n')) { 409 memset(&hints, 0, sizeof(hints)); 410 hints.ai_family = PF_UNSPEC; 411 hints.ai_socktype = SOCK_DGRAM; /*dummy*/ 412 hints.ai_flags = AI_NUMERICHOST; 413 sprintf(sbuf, "%u", NAMESERVER_PORT); 414 if (getaddrinfo(cp, sbuf, &hints, &ai) == 0) { 415 if (ai->ai_addrlen <= minsiz) { 416 if (statp->_u._ext.ext != NULL) { 417 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 418 ai->ai_addr, ai->ai_addrlen); 419 } 420 if (ai->ai_addrlen <= 421 sizeof(statp->nsaddr_list[nserv])) { 422 memcpy(&statp->nsaddr_list[nserv], 423 ai->ai_addr, ai->ai_addrlen); 424 } else 425 statp->nsaddr_list[nserv].sin_family = 0; 426 nserv++; 427 } 428 freeaddrinfo(ai); 429 } 430 } 431 continue; 432 } 433#ifdef RESOLVSORT 434 if (MATCH(buf, "sortlist")) { 435 struct in_addr a; 436 struct in6_addr a6; 437 int m, i; 438 u_char *u; 439 struct __res_state_ext *ext = statp->_u._ext.ext; 440 441 cp = buf + sizeof("sortlist") - 1; 442 while (nsort < MAXRESOLVSORT) { 443 while (*cp == ' ' || *cp == '\t') 444 cp++; 445 if (*cp == '\0' || *cp == '\n' || *cp == ';') 446 break; 447 net = cp; 448 while (*cp && !ISSORTMASK(*cp) && *cp != ';' && 449 isascii(*cp) && !isspace((unsigned char)*cp)) 450 cp++; 451 n = *cp; 452 *cp = 0; 453 if (inet_aton(net, &a)) { 454 statp->sort_list[nsort].addr = a; 455 if (ISSORTMASK(n)) { 456 *cp++ = n; 457 net = cp; 458 while (*cp && *cp != ';' && 459 isascii(*cp) && 460 !isspace((unsigned char)*cp)) 461 cp++; 462 n = *cp; 463 *cp = 0; 464 if (inet_aton(net, &a)) { 465 statp->sort_list[nsort].mask = a.s_addr; 466 } else { 467 statp->sort_list[nsort].mask = 468 net_mask(statp->sort_list[nsort].addr); 469 } 470 } else { 471 statp->sort_list[nsort].mask = 472 net_mask(statp->sort_list[nsort].addr); 473 } 474 ext->sort_list[nsort].af = AF_INET; 475 ext->sort_list[nsort].addr.ina = 476 statp->sort_list[nsort].addr; 477 ext->sort_list[nsort].mask.ina.s_addr = 478 statp->sort_list[nsort].mask; 479 nsort++; 480 } 481 else if (inet_pton(AF_INET6, net, &a6) == 1) { 482 483 ext->sort_list[nsort].af = AF_INET6; 484 ext->sort_list[nsort].addr.in6a = a6; 485 u = (u_char *)&ext->sort_list[nsort].mask.in6a; 486 *cp++ = n; 487 net = cp; 488 while (*cp && *cp != ';' && 489 isascii(*cp) && !isspace(*cp)) 490 cp++; 491 m = n; 492 n = *cp; 493 *cp = 0; 494 switch (m) { 495 case '/': 496 m = atoi(net); 497 break; 498 case '&': 499 if (inet_pton(AF_INET6, net, u) == 1) { 500 m = -1; 501 break; 502 } 503 /*FALLTHROUGH*/ 504 default: 505 m = sizeof(struct in6_addr) * CHAR_BIT; 506 break; 507 } 508 if (m >= 0) { 509 for (i = 0; i < sizeof(struct in6_addr); i++) { 510 if (m <= 0) { 511 *u = 0; 512 } else { 513 m -= CHAR_BIT; 514 *u = (u_char)~0; 515 if (m < 0) 516 *u <<= -m; 517 } 518 u++; 519 } 520 } 521 statp->sort_list[nsort].addr.s_addr = 522 (u_int32_t)0xffffffff; 523 statp->sort_list[nsort].mask = 524 (u_int32_t)0xffffffff; 525 nsort++; 526 } 527 *cp = n; 528 } 529 continue; 530 } 531#endif 532 if (MATCH(buf, "options")) { 533 res_setoptions(statp, buf + sizeof("options") - 1, "conf"); 534 continue; 535 } 536 } 537 if (nserv > 0) 538 statp->nscount = nserv; 539#ifdef RESOLVSORT 540 statp->nsort = nsort; 541#endif 542 (void) fclose(fp); 543 } 544/* 545 * Last chance to get a nameserver. This should not normally 546 * be necessary 547 */ 548#ifdef NO_RESOLV_CONF 549 if(nserv == 0) 550 nserv = get_nameservers(statp); 551#endif 552 553 if (statp->defdname[0] == 0 && 554 gethostname(buf, sizeof(statp->defdname) - 1) == 0 && 555 (cp = strchr(buf, '.')) != NULL) 556 strcpy(statp->defdname, cp + 1); 557 558 /* find components of local domain that might be searched */ 559 if (havesearch == 0) { 560 pp = statp->dnsrch; 561 *pp++ = statp->defdname; 562 *pp = NULL; 563 564 dots = 0; 565 for (cp = statp->defdname; *cp; cp++) 566 dots += (*cp == '.'); 567 568 cp = statp->defdname; 569 while (pp < statp->dnsrch + MAXDFLSRCH) { 570 if (dots < LOCALDOMAINPARTS) 571 break; 572 cp = strchr(cp, '.') + 1; /*%< we know there is one */ 573 *pp++ = cp; 574 dots--; 575 } 576 *pp = NULL; 577#ifdef DEBUG 578 if (statp->options & RES_DEBUG) { 579 printf(";; res_init()... default dnsrch list:\n"); 580 for (pp = statp->dnsrch; *pp; pp++) 581 printf(";;\t%s\n", *pp); 582 printf(";;\t..END..\n"); 583 } 584#endif 585 } 586 587 if (issetugid()) 588 statp->options |= RES_NOALIASES; 589 else if ((cp = getenv("RES_OPTIONS")) != NULL) 590 res_setoptions(statp, cp, "env"); 591 statp->options |= RES_INIT; 592 return (statp->res_h_errno); 593} 594 595static void 596res_setoptions(res_state statp, const char *options, const char *source) 597{ 598 const char *cp = options; 599 int i; 600 struct __res_state_ext *ext = statp->_u._ext.ext; 601 602#ifdef DEBUG 603 if (statp->options & RES_DEBUG) 604 printf(";; res_setoptions(\"%s\", \"%s\")...\n", 605 options, source); 606#endif 607 while (*cp) { 608 /* skip leading and inner runs of spaces */ 609 while (*cp == ' ' || *cp == '\t') 610 cp++; 611 /* search for and process individual options */ 612 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) { 613 i = atoi(cp + sizeof("ndots:") - 1); 614 if (i <= RES_MAXNDOTS) 615 statp->ndots = i; 616 else 617 statp->ndots = RES_MAXNDOTS; 618#ifdef DEBUG 619 if (statp->options & RES_DEBUG) 620 printf(";;\tndots=%d\n", statp->ndots); 621#endif 622 } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) { 623 i = atoi(cp + sizeof("timeout:") - 1); 624 if (i <= RES_MAXRETRANS) 625 statp->retrans = i; 626 else 627 statp->retrans = RES_MAXRETRANS; 628#ifdef DEBUG 629 if (statp->options & RES_DEBUG) 630 printf(";;\ttimeout=%d\n", statp->retrans); 631#endif 632#ifdef SOLARIS2 633 } else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) { 634 /* 635 * For backward compatibility, 'retrans' is 636 * supported as an alias for 'timeout', though 637 * without an imposed maximum. 638 */ 639 statp->retrans = atoi(cp + sizeof("retrans:") - 1); 640 } else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){ 641 /* 642 * For backward compatibility, 'retry' is 643 * supported as an alias for 'attempts', though 644 * without an imposed maximum. 645 */ 646 statp->retry = atoi(cp + sizeof("retry:") - 1); 647#endif /* SOLARIS2 */ 648 } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){ 649 i = atoi(cp + sizeof("attempts:") - 1); 650 if (i <= RES_MAXRETRY) 651 statp->retry = i; 652 else 653 statp->retry = RES_MAXRETRY; 654#ifdef DEBUG 655 if (statp->options & RES_DEBUG) 656 printf(";;\tattempts=%d\n", statp->retry); 657#endif 658 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) { 659#ifdef DEBUG 660 if (!(statp->options & RES_DEBUG)) { 661 printf(";; res_setoptions(\"%s\", \"%s\")..\n", 662 options, source); 663 statp->options |= RES_DEBUG; 664 } 665 printf(";;\tdebug\n"); 666#endif 667 } else if (!strncmp(cp, "no_tld_query", 668 sizeof("no_tld_query") - 1) || 669 !strncmp(cp, "no-tld-query", 670 sizeof("no-tld-query") - 1)) { 671 statp->options |= RES_NOTLDQUERY; 672 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) { 673 statp->options |= RES_USE_INET6; 674 } else if (!strncmp(cp, "insecure1", sizeof("insecure1") - 1)) { 675 statp->options |= RES_INSECURE1; 676 } else if (!strncmp(cp, "insecure2", sizeof("insecure2") - 1)) { 677 statp->options |= RES_INSECURE2; 678 } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) { 679 statp->options |= RES_ROTATE; 680 } else if (!strncmp(cp, "no-check-names", 681 sizeof("no-check-names") - 1)) { 682 statp->options |= RES_NOCHECKNAME; 683 } else if (!strncmp(cp, "reload-period:", 684 sizeof("reload-period:") - 1)) { 685 if (ext != NULL) { 686 ext->reload_period = (u_short) 687 atoi(cp + sizeof("reload-period:") - 1); 688 } 689 } 690#ifdef RES_USE_EDNS0 691 else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) { 692 statp->options |= RES_USE_EDNS0; 693 } 694#endif 695#ifndef _LIBC 696 else if (!strncmp(cp, "dname", sizeof("dname") - 1)) { 697 statp->options |= RES_USE_DNAME; 698 } 699 else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) { 700 if (ext == NULL) 701 goto skip; 702 cp += sizeof("nibble:") - 1; 703 i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1); 704 strncpy(ext->nsuffix, cp, i); 705 ext->nsuffix[i] = '\0'; 706 } 707 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) { 708 if (ext == NULL) 709 goto skip; 710 cp += sizeof("nibble2:") - 1; 711 i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1); 712 strncpy(ext->nsuffix2, cp, i); 713 ext->nsuffix2[i] = '\0'; 714 } 715 else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) { 716 cp += sizeof("v6revmode:") - 1; 717 /* "nibble" and "bitstring" used to be valid */ 718 if (!strncmp(cp, "single", sizeof("single") - 1)) { 719 statp->options |= RES_NO_NIBBLE2; 720 } else if (!strncmp(cp, "both", sizeof("both") - 1)) { 721 statp->options &= 722 ~RES_NO_NIBBLE2; 723 } 724 } 725#endif 726 else { 727 /* XXX - print a warning here? */ 728 } 729#ifndef _LIBC 730 skip: 731#endif 732 /* skip to next run of spaces */ 733 while (*cp && *cp != ' ' && *cp != '\t') 734 cp++; 735 } 736} 737 738#ifdef RESOLVSORT 739/* XXX - should really support CIDR which means explicit masks always. */ 740static u_int32_t 741net_mask(struct in_addr in) /*!< XXX - should really use system's version of this */ 742{ 743 u_int32_t i = ntohl(in.s_addr); 744 745 if (IN_CLASSA(i)) 746 return (htonl(IN_CLASSA_NET)); 747 else if (IN_CLASSB(i)) 748 return (htonl(IN_CLASSB_NET)); 749 return (htonl(IN_CLASSC_NET)); 750} 751#endif 752 753static u_char srnd[16]; 754 755void 756res_rndinit(res_state statp) 757{ 758 struct timeval now; 759 u_int32_t u32; 760 u_int16_t u16; 761 u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd; 762 763 gettimeofday(&now, NULL); 764 u32 = now.tv_sec; 765 memcpy(rnd, &u32, 4); 766 u32 = now.tv_usec; 767 memcpy(rnd + 4, &u32, 4); 768 u32 += now.tv_sec; 769 memcpy(rnd + 8, &u32, 4); 770 u16 = getpid(); 771 memcpy(rnd + 12, &u16, 2); 772} 773 774u_int 775res_nrandomid(res_state statp) { 776 struct timeval now; 777 u_int16_t u16; 778 MD5_CTX ctx; 779 u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd; 780 781 gettimeofday(&now, NULL); 782 u16 = (u_int16_t) (now.tv_sec ^ now.tv_usec); 783 memcpy(rnd + 14, &u16, 2); 784#ifndef HAVE_MD5 785 MD5_Init(&ctx); 786 MD5_Update(&ctx, rnd, 16); 787 MD5_Final(rnd, &ctx); 788#else 789 MD5Init(&ctx); 790 MD5Update(&ctx, rnd, 16); 791 MD5Final(rnd, &ctx); 792#endif 793 memcpy(&u16, rnd + 14, 2); 794 return ((u_int) u16); 795} 796 797/*% 798 * This routine is for closing the socket if a virtual circuit is used and 799 * the program wants to close it. This provides support for endhostent() 800 * which expects to close the socket. 801 * 802 * This routine is not expected to be user visible. 803 */ 804void 805res_nclose(res_state statp) { 806 int ns; 807 808 if (statp->_vcsock >= 0) { 809 (void) _close(statp->_vcsock); 810 statp->_vcsock = -1; 811 statp->_flags &= ~(RES_F_VC | RES_F_CONN); 812 } 813 for (ns = 0; ns < statp->_u._ext.nscount; ns++) { 814 if (statp->_u._ext.nssocks[ns] != -1) { 815 (void) _close(statp->_u._ext.nssocks[ns]); 816 statp->_u._ext.nssocks[ns] = -1; 817 } 818 } 819} 820 821void 822res_ndestroy(res_state statp) { 823 res_nclose(statp); 824 if (statp->_u._ext.ext != NULL) { 825 free(statp->_u._ext.ext); 826 statp->_u._ext.ext = NULL; 827 } 828 if (statp->_rnd != NULL) { 829 free(statp->_rnd); 830 statp->_rnd = NULL; 831 } 832 statp->options &= ~RES_INIT; 833} 834 835#ifndef _LIBC 836const char * 837res_get_nibblesuffix(res_state statp) { 838 if (statp->_u._ext.ext) 839 return (statp->_u._ext.ext->nsuffix); 840 return ("ip6.arpa"); 841} 842 843const char * 844res_get_nibblesuffix2(res_state statp) { 845 if (statp->_u._ext.ext) 846 return (statp->_u._ext.ext->nsuffix2); 847 return ("ip6.int"); 848} 849#endif 850 851void 852res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) { 853 int i, nserv; 854 size_t size; 855 856 /* close open servers */ 857 res_nclose(statp); 858 859 /* cause rtt times to be forgotten */ 860 statp->_u._ext.nscount = 0; 861 862 nserv = 0; 863 for (i = 0; i < cnt && nserv < MAXNS; i++) { 864 switch (set->sin.sin_family) { 865 case AF_INET: 866 size = sizeof(set->sin); 867 if (statp->_u._ext.ext) 868 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 869 &set->sin, size); 870 if (size <= sizeof(statp->nsaddr_list[nserv])) 871 memcpy(&statp->nsaddr_list[nserv], 872 &set->sin, size); 873 else 874 statp->nsaddr_list[nserv].sin_family = 0; 875 nserv++; 876 break; 877 878#ifdef HAS_INET6_STRUCTS 879 case AF_INET6: 880 size = sizeof(set->sin6); 881 if (statp->_u._ext.ext) 882 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 883 &set->sin6, size); 884 if (size <= sizeof(statp->nsaddr_list[nserv])) 885 memcpy(&statp->nsaddr_list[nserv], 886 &set->sin6, size); 887 else 888 statp->nsaddr_list[nserv].sin_family = 0; 889 nserv++; 890 break; 891#endif 892 893 default: 894 break; 895 } 896 set++; 897 } 898 statp->nscount = nserv; 899 900} 901 902int 903res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) { 904 int i; 905 size_t size; 906 u_int16_t family; 907 908 for (i = 0; i < statp->nscount && i < cnt; i++) { 909 if (statp->_u._ext.ext) 910 family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family; 911 else 912 family = statp->nsaddr_list[i].sin_family; 913 914 switch (family) { 915 case AF_INET: 916 size = sizeof(set->sin); 917 if (statp->_u._ext.ext) 918 memcpy(&set->sin, 919 &statp->_u._ext.ext->nsaddrs[i], 920 size); 921 else 922 memcpy(&set->sin, &statp->nsaddr_list[i], 923 size); 924 break; 925 926#ifdef HAS_INET6_STRUCTS 927 case AF_INET6: 928 size = sizeof(set->sin6); 929 if (statp->_u._ext.ext) 930 memcpy(&set->sin6, 931 &statp->_u._ext.ext->nsaddrs[i], 932 size); 933 else 934 memcpy(&set->sin6, &statp->nsaddr_list[i], 935 size); 936 break; 937#endif 938 939 default: 940 set->sin.sin_family = 0; 941 break; 942 } 943 set++; 944 } 945 return (statp->nscount); 946} 947 948/*! \file */ 949