1 /* $NetBSD: res_init.c,v 1.30 2015/02/24 17:56:20 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. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 34 * 35 * Permission to use, copy, modify, and distribute this software for any 36 * purpose with or without fee is hereby granted, provided that the above 37 * copyright notice and this permission notice appear in all copies, and that 38 * the name of Digital Equipment Corporation not be used in advertising or 39 * publicity pertaining to distribution of the document or software without 40 * specific, written prior permission. 41 * 42 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 43 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 44 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 45 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 46 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 47 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 48 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 49 * SOFTWARE. 50 */ 51 52 /* 53 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 54 * Portions Copyright (c) 1996-1999 by Internet Software Consortium. 55 * 56 * Permission to use, copy, modify, and distribute this software for any 57 * purpose with or without fee is hereby granted, provided that the above 58 * copyright notice and this permission notice appear in all copies. 59 * 60 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 61 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 62 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 63 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 64 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 65 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 66 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 67 */ 68 69 #include <sys/cdefs.h> 70 #if defined(LIBC_SCCS) && !defined(lint) 71 #ifdef notdef 72 static const char sccsid[] = "@(#)res_init.c 8.1 (Berkeley) 6/7/93"; 73 static const char rcsid[] = "Id: res_init.c,v 1.26 2008/12/11 09:59:00 marka Exp"; 74 #else 75 __RCSID("$NetBSD: res_init.c,v 1.30 2015/02/24 17:56:20 christos Exp $"); 76 #endif 77 #endif /* LIBC_SCCS and not lint */ 78 79 #include "port_before.h" 80 81 #include "namespace.h" 82 #include <sys/types.h> 83 #include <sys/param.h> 84 #include <sys/socket.h> 85 #include <sys/stat.h> 86 #include <sys/time.h> 87 #if !defined(__minix) 88 #include <sys/event.h> 89 #endif /* !defined(__minix) */ 90 91 #include <netinet/in.h> 92 #include <arpa/inet.h> 93 #include <arpa/nameser.h> 94 95 #include <ctype.h> 96 #include <stdio.h> 97 #include <stdlib.h> 98 #include <string.h> 99 #include <unistd.h> 100 #include <fcntl.h> 101 #include <netdb.h> 102 103 #define HAVE_MD5 104 #include <md5.h> 105 106 #ifndef HAVE_MD5 107 # include "../dst/md5.h" 108 #else 109 # ifdef SOLARIS2 110 # include <sys/md5.h> 111 # endif 112 #endif 113 #ifndef _MD5_H_ 114 # define _MD5_H_ 1 /*%< make sure we do not include rsaref md5.h file */ 115 #endif 116 117 #include "port_after.h" 118 119 #if 0 120 #ifdef __weak_alias 121 __weak_alias(res_ninit,_res_ninit) 122 __weak_alias(res_randomid,__res_randomid) 123 __weak_alias(res_nclose,_res_nclose) 124 __weak_alias(res_ndestroy,_res_ndestroy) 125 __weak_alias(res_get_nibblesuffix,__res_get_nibblesuffix) 126 __weak_alias(res_get_nibblesuffix2,__res_get_nibblesuffix2) 127 __weak_alias(res_getservers,__res_getservers) 128 __weak_alias(res_setservers,__res_setservers) 129 #endif 130 #endif 131 132 133 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */ 134 #include <resolv.h> 135 136 #include "res_private.h" 137 138 #define RESOLVSORT 139 /*% Options. Should all be left alone. */ 140 #ifndef DEBUG 141 #define DEBUG 142 #endif 143 144 #ifdef SOLARIS2 145 #include <sys/systeminfo.h> 146 #endif 147 148 static void res_setoptions(res_state, const char *, const char *); 149 150 #ifdef RESOLVSORT 151 static const char sort_mask[] = "/&"; 152 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL) 153 static uint32_t net_mask(struct in_addr); 154 #endif 155 156 #if !defined(isascii) /*%< XXX - could be a function */ 157 # define isascii(c) (!(c & 0200)) 158 #endif 159 160 static struct timespec __res_conf_time; 161 #if !defined(__minix) 162 static const struct timespec ts = { 0, 0 }; 163 #endif /* !defined(__minix) */ 164 165 const char *__res_conf_name = _PATH_RESCONF; 166 167 /* 168 * Resolver state default settings. 169 */ 170 171 /*% 172 * Set up default settings. If the configuration file exist, the values 173 * there will have precedence. Otherwise, the server address is set to 174 * INADDR_ANY and the default domain name comes from the gethostname(). 175 * 176 * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1 177 * rather than INADDR_ANY ("0.0.0.0") as the default name server address 178 * since it was noted that INADDR_ANY actually meant ``the first interface 179 * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface, 180 * it had to be "up" in order for you to reach your own name server. It 181 * was later decided that since the recommended practice is to always 182 * install local static routes through 127.0.0.1 for all your network 183 * interfaces, that we could solve this problem without a code change. 184 * 185 * The configuration file should always be used, since it is the only way 186 * to specify a default domain. If you are running a server on your local 187 * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1" 188 * in the configuration file. 189 * 190 * Return 0 if completes successfully, -1 on error 191 */ 192 int 193 res_ninit(res_state statp) { 194 return (__res_vinit(statp, 0)); 195 } 196 197 /*% This function has to be reachable by res_data.c but not publically. */ 198 int 199 __res_vinit(res_state statp, int preinit) { 200 register FILE *fp; 201 register char *cp, **pp; 202 register int n; 203 char buf[BUFSIZ]; 204 int nserv = 0; /*%< number of nameserver records read from file */ 205 int haveenv = 0; 206 int havesearch = 0; 207 #ifdef RESOLVSORT 208 int nsort = 0; 209 char *net; 210 #endif 211 int dots; 212 union res_sockaddr_union u[2]; 213 int maxns = MAXNS; 214 215 RES_SET_H_ERRNO(statp, 0); 216 217 if ((statp->options & RES_INIT) != 0U) 218 res_ndestroy(statp); 219 220 if (!preinit) { 221 statp->retrans = RES_TIMEOUT; 222 statp->retry = RES_DFLRETRY; 223 statp->options = RES_DEFAULT; 224 } 225 statp->_rnd = malloc(16); 226 res_rndinit(statp); 227 statp->id = res_nrandomid(statp); 228 229 memset(u, 0, sizeof(u)); 230 #ifdef USELOOPBACK 231 u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1); 232 #else 233 u[nserv].sin.sin_addr.s_addr = INADDR_ANY; 234 #endif 235 u[nserv].sin.sin_family = AF_INET; 236 u[nserv].sin.sin_port = htons(NAMESERVER_PORT); 237 #ifdef HAVE_SA_LEN 238 u[nserv].sin.sin_len = sizeof(struct sockaddr_in); 239 #endif 240 nserv++; 241 #ifdef HAS_INET6_STRUCTS 242 #ifdef USELOOPBACK 243 u[nserv].sin6.sin6_addr = in6addr_loopback; 244 #else 245 u[nserv].sin6.sin6_addr = in6addr_any; 246 #endif 247 u[nserv].sin6.sin6_family = AF_INET6; 248 u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT); 249 #ifdef HAVE_SA_LEN 250 u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6); 251 #endif 252 nserv++; 253 #endif 254 statp->nscount = 0; 255 statp->ndots = 1; 256 statp->pfcode = 0; 257 statp->_vcsock = -1; 258 statp->_flags = 0; 259 statp->qhook = NULL; 260 statp->rhook = NULL; 261 statp->_u._ext.nscount = 0; 262 statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext)); 263 if (statp->_u._ext.ext != NULL) { 264 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext)); 265 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr; 266 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa"); 267 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int"); 268 } else { 269 /* 270 * Historically res_init() rarely, if at all, failed. 271 * Examples and applications exist which do not check 272 * our return code. Furthermore several applications 273 * simply call us to get the systems domainname. So 274 * rather than immediately fail here we store the 275 * failure, which is returned later, in h_errno. And 276 * prevent the collection of 'nameserver' information 277 * by setting maxns to 0. Thus applications that fail 278 * to check our return code wont be able to make 279 * queries anyhow. 280 */ 281 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 282 maxns = 0; 283 } 284 #ifdef RESOLVSORT 285 statp->nsort = 0; 286 #endif 287 res_setservers(statp, u, nserv); 288 289 #ifdef SOLARIS2 290 /* 291 * The old libresolv derived the defaultdomain from NIS/NIS+. 292 * We want to keep this behaviour 293 */ 294 { 295 char buf[sizeof(statp->defdname)], *cp; 296 int ret; 297 298 if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 && 299 (unsigned int)ret <= sizeof(buf)) { 300 if (buf[0] == '+') 301 buf[0] = '.'; 302 cp = strchr(buf, '.'); 303 cp = (cp == NULL) ? buf : (cp + 1); 304 (void)strlcpy(statp->defdname, cp, 305 sizeof(statp->defdname)); 306 } 307 } 308 #endif /* SOLARIS2 */ 309 310 /* Allow user to override the local domain definition */ 311 if ((cp = getenv("LOCALDOMAIN")) != NULL) { 312 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 313 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 314 haveenv++; 315 316 /* 317 * Set search list to be blank-separated strings 318 * from rest of env value. Permits users of LOCALDOMAIN 319 * to still have a search list, and anyone to set the 320 * one that they want to use as an individual (even more 321 * important now that the rfc1535 stuff restricts searches) 322 */ 323 cp = statp->defdname; 324 pp = statp->dnsrch; 325 *pp++ = cp; 326 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) { 327 if (*cp == '\n') /*%< silly backwards compat */ 328 break; 329 else if (*cp == ' ' || *cp == '\t') { 330 *cp = 0; 331 n = 1; 332 } else if (n) { 333 *pp++ = cp; 334 n = 0; 335 havesearch = 1; 336 } 337 } 338 /* null terminate last domain if there are excess */ 339 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n') 340 cp++; 341 *cp = '\0'; 342 *pp++ = 0; 343 } 344 345 #define MATCH(line, name) \ 346 (!strncmp(line, name, sizeof(name) - 1) && \ 347 (line[sizeof(name) - 1] == ' ' || \ 348 line[sizeof(name) - 1] == '\t')) 349 350 nserv = 0; 351 if ((fp = fopen(__res_conf_name, "re")) != NULL) { 352 struct stat st; 353 #if !defined(__minix) 354 struct kevent kc; 355 #endif /* !defined(__minix) */ 356 357 /* read the config file */ 358 while (fgets(buf, (int)sizeof(buf), fp) != NULL) { 359 /* skip comments */ 360 if (*buf == ';' || *buf == '#') 361 continue; 362 /* read default domain name */ 363 if (MATCH(buf, "domain")) { 364 if (haveenv) /*%< skip if have from environ */ 365 continue; 366 cp = buf + sizeof("domain") - 1; 367 while (*cp == ' ' || *cp == '\t') 368 cp++; 369 if ((*cp == '\0') || (*cp == '\n')) 370 continue; 371 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 372 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 373 if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL) 374 *cp = '\0'; 375 havesearch = 0; 376 continue; 377 } 378 /* set search list */ 379 if (MATCH(buf, "search")) { 380 if (haveenv) /*%< skip if have from environ */ 381 continue; 382 cp = buf + sizeof("search") - 1; 383 while (*cp == ' ' || *cp == '\t') 384 cp++; 385 if ((*cp == '\0') || (*cp == '\n')) 386 continue; 387 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 388 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 389 if ((cp = strchr(statp->defdname, '\n')) != NULL) 390 *cp = '\0'; 391 /* 392 * Set search list to be blank-separated strings 393 * on rest of line. 394 */ 395 cp = statp->defdname; 396 pp = statp->dnsrch; 397 *pp++ = cp; 398 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) { 399 if (*cp == ' ' || *cp == '\t') { 400 *cp = 0; 401 n = 1; 402 } else if (n) { 403 *pp++ = cp; 404 n = 0; 405 } 406 } 407 /* null terminate last domain if there are excess */ 408 while (*cp != '\0' && *cp != ' ' && *cp != '\t') 409 cp++; 410 *cp = '\0'; 411 *pp++ = 0; 412 havesearch = 1; 413 continue; 414 } 415 /* read nameservers to query */ 416 if (MATCH(buf, "nameserver") && nserv < maxns) { 417 struct addrinfo hints, *ai; 418 char sbuf[NI_MAXSERV]; 419 const size_t minsiz = 420 sizeof(statp->_u._ext.ext->nsaddrs[0]); 421 422 cp = buf + sizeof("nameserver") - 1; 423 while (*cp == ' ' || *cp == '\t') 424 cp++; 425 cp[strcspn(cp, ";# \t\n")] = '\0'; 426 if ((*cp != '\0') && (*cp != '\n')) { 427 memset(&hints, 0, sizeof(hints)); 428 hints.ai_family = PF_UNSPEC; 429 hints.ai_socktype = SOCK_DGRAM; /*dummy*/ 430 hints.ai_flags = AI_NUMERICHOST; 431 sprintf(sbuf, "%u", NAMESERVER_PORT); 432 if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 && 433 ai->ai_addrlen <= minsiz) { 434 if (statp->_u._ext.ext != NULL) { 435 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 436 ai->ai_addr, ai->ai_addrlen); 437 } 438 if (ai->ai_addrlen <= 439 sizeof(statp->nsaddr_list[nserv])) { 440 memcpy(&statp->nsaddr_list[nserv], 441 ai->ai_addr, ai->ai_addrlen); 442 } else 443 statp->nsaddr_list[nserv].sin_family = 0; 444 freeaddrinfo(ai); 445 nserv++; 446 } 447 } 448 continue; 449 } 450 #ifdef RESOLVSORT 451 if (MATCH(buf, "sortlist")) { 452 struct in_addr a; 453 454 cp = buf + sizeof("sortlist") - 1; 455 while (nsort < MAXRESOLVSORT) { 456 while (*cp == ' ' || *cp == '\t') 457 cp++; 458 if (*cp == '\0' || *cp == '\n' || *cp == ';') 459 break; 460 net = cp; 461 while (*cp && !ISSORTMASK(*cp) && *cp != ';' && 462 isascii(*cp) && !isspace((unsigned char)*cp)) 463 cp++; 464 n = *cp; 465 *cp = 0; 466 if (inet_aton(net, &a)) { 467 statp->sort_list[nsort].addr = a; 468 if (ISSORTMASK(n)) { 469 *cp++ = n; 470 net = cp; 471 while (*cp && *cp != ';' && 472 isascii(*cp) && 473 !isspace((unsigned char)*cp)) 474 cp++; 475 n = *cp; 476 *cp = 0; 477 if (inet_aton(net, &a)) { 478 statp->sort_list[nsort].mask = a.s_addr; 479 } else { 480 statp->sort_list[nsort].mask = 481 net_mask(statp->sort_list[nsort].addr); 482 } 483 } else { 484 statp->sort_list[nsort].mask = 485 net_mask(statp->sort_list[nsort].addr); 486 } 487 nsort++; 488 } 489 *cp = n; 490 } 491 continue; 492 } 493 #endif 494 if (MATCH(buf, "options")) { 495 res_setoptions(statp, buf + sizeof("options") - 1, "conf"); 496 continue; 497 } 498 } 499 if (nserv > 0) 500 statp->nscount = nserv; 501 #ifdef RESOLVSORT 502 statp->nsort = nsort; 503 #endif 504 statp->_u._ext.ext->resfd = fcntl(fileno(fp), F_DUPFD_CLOEXEC); 505 (void) fclose(fp); 506 if (fstat(statp->_u._ext.ext->resfd, &st) != -1) 507 __res_conf_time = statp->_u._ext.ext->res_conf_time = 508 st.st_mtimespec; 509 #if !defined(__minix) 510 statp->_u._ext.ext->kq = kqueue1(O_CLOEXEC); 511 EV_SET(&kc, statp->_u._ext.ext->resfd, EVFILT_VNODE, 512 EV_ADD|EV_ENABLE|EV_CLEAR, NOTE_DELETE|NOTE_WRITE| NOTE_EXTEND| 513 NOTE_ATTRIB|NOTE_LINK|NOTE_RENAME|NOTE_REVOKE, 0, 0); 514 (void)kevent(statp->_u._ext.ext->kq, &kc, 1, NULL, 0, &ts); 515 #else 516 statp->_u._ext.ext->kq = -1; 517 #endif /* !defined(__minix) */ 518 } else { 519 statp->_u._ext.ext->kq = -1; 520 statp->_u._ext.ext->resfd = -1; 521 } 522 /* 523 * Last chance to get a nameserver. This should not normally 524 * be necessary 525 */ 526 #ifdef NO_RESOLV_CONF 527 if(nserv == 0) 528 nserv = get_nameservers(statp); 529 #endif 530 531 if (statp->defdname[0] == 0 && 532 gethostname(buf, sizeof(statp->defdname) - 1) == 0 && 533 (cp = strchr(buf, '.')) != NULL) 534 strcpy(statp->defdname, cp + 1); 535 536 /* find components of local domain that might be searched */ 537 if (havesearch == 0) { 538 pp = statp->dnsrch; 539 *pp++ = statp->defdname; 540 *pp = NULL; 541 542 dots = 0; 543 for (cp = statp->defdname; *cp; cp++) 544 dots += (*cp == '.'); 545 546 cp = statp->defdname; 547 while (pp < statp->dnsrch + MAXDFLSRCH) { 548 if (dots < LOCALDOMAINPARTS) 549 break; 550 cp = strchr(cp, '.') + 1; /*%< we know there is one */ 551 *pp++ = cp; 552 dots--; 553 } 554 *pp = NULL; 555 #ifdef DEBUG 556 if (statp->options & RES_DEBUG) { 557 printf(";; res_init()... default dnsrch list:\n"); 558 for (pp = statp->dnsrch; *pp; pp++) 559 printf(";;\t%s\n", *pp); 560 printf(";;\t..END..\n"); 561 } 562 #endif 563 } 564 565 if ((cp = getenv("RES_OPTIONS")) != NULL) 566 res_setoptions(statp, cp, "env"); 567 statp->options |= RES_INIT; 568 return (statp->res_h_errno); 569 } 570 571 int 572 res_check(res_state statp, struct timespec *mtime) 573 { 574 #if defined(__minix) 575 /* 576 * XXX: No update on change. 577 */ 578 return 0; 579 #else 580 /* 581 * If the times are equal, then we check if there 582 * was a kevent related to resolv.conf and reload. 583 * If the times are not equal, then we don't bother 584 * to check the kevent, because another thread already 585 * did, loaded and changed the time. 586 */ 587 if (timespeccmp(&statp->_u._ext.ext->res_conf_time, 588 &__res_conf_time, ==)) { 589 struct kevent ke; 590 if (statp->_u._ext.ext->kq == -1) 591 goto out; 592 593 switch (kevent(statp->_u._ext.ext->kq, NULL, 0, &ke, 1, &ts)) { 594 case 0: 595 case -1: 596 out: 597 if (mtime) 598 *mtime = __res_conf_time; 599 return 0; 600 default: 601 break; 602 } 603 } 604 (void)__res_vinit(statp, 0); 605 if (mtime) 606 *mtime = __res_conf_time; 607 return 1; 608 #endif /* defined(__minix) */ 609 } 610 611 static void 612 res_setoptions(res_state statp, const char *options, const char *source) 613 { 614 const char *cp = options; 615 int i; 616 size_t j; 617 struct __res_state_ext *ext = statp->_u._ext.ext; 618 619 #ifdef DEBUG 620 if (statp->options & RES_DEBUG) 621 printf(";; res_setoptions(\"%s\", \"%s\")...\n", 622 options, source); 623 #endif 624 while (*cp) { 625 /* skip leading and inner runs of spaces */ 626 while (*cp == ' ' || *cp == '\t') 627 cp++; 628 /* search for and process individual options */ 629 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) { 630 i = atoi(cp + sizeof("ndots:") - 1); 631 if (i <= RES_MAXNDOTS) 632 statp->ndots = i; 633 else 634 statp->ndots = RES_MAXNDOTS; 635 #ifdef DEBUG 636 if (statp->options & RES_DEBUG) 637 printf(";;\tndots=%d\n", statp->ndots); 638 #endif 639 } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) { 640 i = atoi(cp + sizeof("timeout:") - 1); 641 if (i <= RES_MAXRETRANS) 642 statp->retrans = i; 643 else 644 statp->retrans = RES_MAXRETRANS; 645 #ifdef DEBUG 646 if (statp->options & RES_DEBUG) 647 printf(";;\ttimeout=%d\n", statp->retrans); 648 #endif 649 #ifdef SOLARIS2 650 } else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) { 651 /* 652 * For backward compatibility, 'retrans' is 653 * supported as an alias for 'timeout', though 654 * without an imposed maximum. 655 */ 656 statp->retrans = atoi(cp + sizeof("retrans:") - 1); 657 } else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){ 658 /* 659 * For backward compatibility, 'retry' is 660 * supported as an alias for 'attempts', though 661 * without an imposed maximum. 662 */ 663 statp->retry = atoi(cp + sizeof("retry:") - 1); 664 #endif /* SOLARIS2 */ 665 } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){ 666 i = atoi(cp + sizeof("attempts:") - 1); 667 if (i <= RES_MAXRETRY) 668 statp->retry = i; 669 else 670 statp->retry = RES_MAXRETRY; 671 #ifdef DEBUG 672 if (statp->options & RES_DEBUG) 673 printf(";;\tattempts=%d\n", statp->retry); 674 #endif 675 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) { 676 #ifdef DEBUG 677 if (!(statp->options & RES_DEBUG)) { 678 printf(";; res_setoptions(\"%s\", \"%s\")..\n", 679 options, source); 680 statp->options |= RES_DEBUG; 681 } 682 printf(";;\tdebug\n"); 683 #endif 684 } else if (!strncmp(cp, "no_tld_query", 685 sizeof("no_tld_query") - 1) || 686 !strncmp(cp, "no-tld-query", 687 sizeof("no-tld-query") - 1)) { 688 statp->options |= RES_NOTLDQUERY; 689 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) { 690 statp->options |= RES_USE_INET6; 691 } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) { 692 statp->options |= RES_ROTATE; 693 } else if (!strncmp(cp, "no-check-names", 694 sizeof("no-check-names") - 1)) { 695 statp->options |= RES_NOCHECKNAME; 696 } else if (!strncmp(cp, "check-names", 697 sizeof("check-names") - 1)) { 698 statp->options &= ~RES_NOCHECKNAME; 699 } 700 #ifdef RES_USE_EDNS0 701 else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) { 702 statp->options |= RES_USE_EDNS0; 703 } 704 #endif 705 else if (!strncmp(cp, "dname", sizeof("dname") - 1)) { 706 statp->options |= RES_USE_DNAME; 707 } 708 else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) { 709 if (ext == NULL) 710 goto skip; 711 cp += sizeof("nibble:") - 1; 712 j = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1); 713 strncpy(ext->nsuffix, cp, j); 714 ext->nsuffix[j] = '\0'; 715 } 716 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) { 717 if (ext == NULL) 718 goto skip; 719 cp += sizeof("nibble2:") - 1; 720 j = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1); 721 strncpy(ext->nsuffix2, cp, j); 722 ext->nsuffix2[j] = '\0'; 723 } 724 else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) { 725 cp += sizeof("v6revmode:") - 1; 726 /* "nibble" and "bitstring" used to be valid */ 727 if (!strncmp(cp, "single", sizeof("single") - 1)) { 728 statp->options |= RES_NO_NIBBLE2; 729 } else if (!strncmp(cp, "both", sizeof("both") - 1)) { 730 statp->options &= 731 ~RES_NO_NIBBLE2; 732 } 733 } 734 else { 735 /* XXX - print a warning here? */ 736 } 737 skip: 738 /* skip to next run of spaces */ 739 while (*cp && *cp != ' ' && *cp != '\t') 740 cp++; 741 } 742 } 743 744 #ifdef RESOLVSORT 745 /* XXX - should really support CIDR which means explicit masks always. */ 746 static uint32_t 747 net_mask(struct in_addr in) /*!< XXX - should really use system's version of this */ 748 { 749 register uint32_t i = ntohl(in.s_addr); 750 751 if (IN_CLASSA(i)) 752 return (htonl(IN_CLASSA_NET)); 753 else if (IN_CLASSB(i)) 754 return (htonl(IN_CLASSB_NET)); 755 return (htonl(IN_CLASSC_NET)); 756 } 757 #endif 758 759 static u_char srnd[16]; 760 761 void 762 res_rndinit(res_state statp) 763 { 764 struct timeval now; 765 uint32_t u32; 766 uint16_t u16; 767 u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd; 768 769 gettimeofday(&now, NULL); 770 u32 = (uint32_t)now.tv_sec; 771 memcpy(rnd, &u32, 4); 772 u32 = now.tv_usec; 773 memcpy(rnd + 4, &u32, 4); 774 u32 += (uint32_t)now.tv_sec; 775 memcpy(rnd + 8, &u32, 4); 776 u16 = getpid(); 777 memcpy(rnd + 12, &u16, 2); 778 } 779 780 u_int 781 res_nrandomid(res_state statp) 782 { 783 struct timeval now; 784 uint16_t u16; 785 MD5_CTX ctx; 786 u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd; 787 788 gettimeofday(&now, NULL); 789 u16 = (uint16_t) (now.tv_sec ^ now.tv_usec); 790 memcpy(rnd + 14, &u16, 2); 791 #ifndef HAVE_MD5 792 MD5_Init(&ctx); 793 MD5_Update(&ctx, rnd, 16); 794 MD5_Final(rnd, &ctx); 795 #else 796 MD5Init(&ctx); 797 MD5Update(&ctx, rnd, 16); 798 MD5Final(rnd, &ctx); 799 #endif 800 memcpy(&u16, rnd + 14, 2); 801 return ((u_int) u16); 802 } 803 804 /*% 805 * This routine is for closing the socket if a virtual circuit is used and 806 * the program wants to close it. This provides support for endhostent() 807 * which expects to close the socket. 808 * 809 * This routine is not expected to be user visible. 810 */ 811 void 812 res_nclose(res_state statp) 813 { 814 int ns; 815 816 if (statp->_vcsock >= 0) { 817 (void) close(statp->_vcsock); 818 statp->_vcsock = -1; 819 statp->_flags &= ~(RES_F_VC | RES_F_CONN); 820 } 821 for (ns = 0; ns < statp->_u._ext.nscount; ns++) { 822 if (statp->_u._ext.nssocks[ns] != -1) { 823 (void) close(statp->_u._ext.nssocks[ns]); 824 statp->_u._ext.nssocks[ns] = -1; 825 } 826 } 827 } 828 829 void 830 res_ndestroy(res_state statp) 831 { 832 res_nclose(statp); 833 if (statp->_u._ext.ext != NULL) { 834 if (statp->_u._ext.ext->kq != -1) 835 (void)close(statp->_u._ext.ext->kq); 836 if (statp->_u._ext.ext->resfd != -1) 837 (void)close(statp->_u._ext.ext->resfd); 838 free(statp->_u._ext.ext); 839 statp->_u._ext.ext = NULL; 840 } 841 if (statp->_rnd != NULL) { 842 free(statp->_rnd); 843 statp->_rnd = NULL; 844 } 845 statp->options &= ~RES_INIT; 846 } 847 848 const char * 849 res_get_nibblesuffix(res_state statp) 850 { 851 if (statp->_u._ext.ext) 852 return (statp->_u._ext.ext->nsuffix); 853 return ("ip6.arpa"); 854 } 855 856 const char * 857 res_get_nibblesuffix2(res_state statp) 858 { 859 if (statp->_u._ext.ext) 860 return (statp->_u._ext.ext->nsuffix2); 861 return ("ip6.int"); 862 } 863 864 void 865 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) 866 { 867 int i, nserv; 868 size_t size; 869 870 /* close open servers */ 871 res_nclose(statp); 872 873 /* cause rtt times to be forgotten */ 874 statp->_u._ext.nscount = 0; 875 876 nserv = 0; 877 for (i = 0; i < cnt && nserv < MAXNS; i++) { 878 switch (set->sin.sin_family) { 879 case AF_INET: 880 size = sizeof(set->sin); 881 if (statp->_u._ext.ext) 882 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 883 &set->sin, size); 884 if (size <= sizeof(statp->nsaddr_list[nserv])) 885 memcpy(&statp->nsaddr_list[nserv], 886 &set->sin, size); 887 else 888 statp->nsaddr_list[nserv].sin_family = 0; 889 nserv++; 890 break; 891 892 #ifdef HAS_INET6_STRUCTS 893 case AF_INET6: 894 size = sizeof(set->sin6); 895 if (statp->_u._ext.ext) 896 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 897 &set->sin6, size); 898 if (size <= sizeof(statp->nsaddr_list[nserv])) 899 memcpy(&statp->nsaddr_list[nserv], 900 &set->sin6, size); 901 else 902 statp->nsaddr_list[nserv].sin_family = 0; 903 nserv++; 904 break; 905 #endif 906 907 default: 908 break; 909 } 910 set++; 911 } 912 statp->nscount = nserv; 913 914 } 915 916 int 917 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) 918 { 919 int i; 920 size_t size; 921 uint16_t family; 922 923 for (i = 0; i < statp->nscount && i < cnt; i++) { 924 if (statp->_u._ext.ext) 925 family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family; 926 else 927 family = statp->nsaddr_list[i].sin_family; 928 929 switch (family) { 930 case AF_INET: 931 size = sizeof(set->sin); 932 if (statp->_u._ext.ext) 933 memcpy(&set->sin, 934 &statp->_u._ext.ext->nsaddrs[i], 935 size); 936 else 937 memcpy(&set->sin, &statp->nsaddr_list[i], 938 size); 939 break; 940 941 #ifdef HAS_INET6_STRUCTS 942 case AF_INET6: 943 size = sizeof(set->sin6); 944 if (statp->_u._ext.ext) 945 memcpy(&set->sin6, 946 &statp->_u._ext.ext->nsaddrs[i], 947 size); 948 else 949 memcpy(&set->sin6, &statp->nsaddr_list[i], 950 size); 951 break; 952 #endif 953 954 default: 955 set->sin.sin_family = 0; 956 break; 957 } 958 set++; 959 } 960 return (statp->nscount); 961 } 962 963 /*! \file */ 964