1 /* $NetBSD: res_init.c,v 1.31 2017/04/19 22:21:07 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 1.31 2017/04/19 22:21:07 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 #include <sys/event.h> 88 89 #include <netinet/in.h> 90 #include <arpa/inet.h> 91 #include <arpa/nameser.h> 92 93 #include <ctype.h> 94 #include <stdio.h> 95 #include <stdlib.h> 96 #include <string.h> 97 #include <unistd.h> 98 #include <fcntl.h> 99 #include <netdb.h> 100 101 #define HAVE_MD5 102 #include <md5.h> 103 104 #ifndef HAVE_MD5 105 # include "../dst/md5.h" 106 #else 107 # ifdef SOLARIS2 108 # include <sys/md5.h> 109 # endif 110 #endif 111 #ifndef _MD5_H_ 112 # define _MD5_H_ 1 /*%< make sure we do not include rsaref md5.h file */ 113 #endif 114 115 #include "port_after.h" 116 117 #if 0 118 #ifdef __weak_alias 119 __weak_alias(res_ninit,_res_ninit) 120 __weak_alias(res_randomid,__res_randomid) 121 __weak_alias(res_nclose,_res_nclose) 122 __weak_alias(res_ndestroy,_res_ndestroy) 123 __weak_alias(res_get_nibblesuffix,__res_get_nibblesuffix) 124 __weak_alias(res_get_nibblesuffix2,__res_get_nibblesuffix2) 125 __weak_alias(res_getservers,__res_getservers) 126 __weak_alias(res_setservers,__res_setservers) 127 #endif 128 #endif 129 130 131 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */ 132 #include <resolv.h> 133 134 #include "res_private.h" 135 136 #define RESOLVSORT 137 /*% Options. Should all be left alone. */ 138 #ifndef DEBUG 139 #define DEBUG 140 #endif 141 142 #ifdef SOLARIS2 143 #include <sys/systeminfo.h> 144 #endif 145 146 static void res_setoptions(res_state, const char *, const char *); 147 148 #ifdef RESOLVSORT 149 static const char sort_mask[] = "/&"; 150 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL) 151 static uint32_t net_mask(struct in_addr); 152 #endif 153 154 #if !defined(isascii) /*%< XXX - could be a function */ 155 # define isascii(c) (!(c & 0200)) 156 #endif 157 158 static struct timespec __res_conf_time; 159 static const struct timespec ts = { 0, 0 }; 160 161 const char *__res_conf_name = _PATH_RESCONF; 162 163 /* 164 * Resolver state default settings. 165 */ 166 167 /*% 168 * Set up default settings. If the configuration file exist, the values 169 * there will have precedence. Otherwise, the server address is set to 170 * INADDR_ANY and the default domain name comes from the gethostname(). 171 * 172 * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1 173 * rather than INADDR_ANY ("0.0.0.0") as the default name server address 174 * since it was noted that INADDR_ANY actually meant ``the first interface 175 * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface, 176 * it had to be "up" in order for you to reach your own name server. It 177 * was later decided that since the recommended practice is to always 178 * install local static routes through 127.0.0.1 for all your network 179 * interfaces, that we could solve this problem without a code change. 180 * 181 * The configuration file should always be used, since it is the only way 182 * to specify a default domain. If you are running a server on your local 183 * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1" 184 * in the configuration file. 185 * 186 * Return 0 if completes successfully, -1 on error 187 */ 188 int 189 res_ninit(res_state statp) { 190 return (__res_vinit(statp, 0)); 191 } 192 193 /*% This function has to be reachable by res_data.c but not publically. */ 194 int 195 __res_vinit(res_state statp, int preinit) { 196 register FILE *fp; 197 register char *cp, **pp; 198 register int n; 199 char buf[BUFSIZ]; 200 int nserv = 0; /*%< number of nameserver records read from file */ 201 int haveenv = 0; 202 int havesearch = 0; 203 #ifdef RESOLVSORT 204 int nsort = 0; 205 char *net; 206 #endif 207 int dots; 208 union res_sockaddr_union u[2]; 209 int maxns = MAXNS; 210 211 RES_SET_H_ERRNO(statp, 0); 212 213 if ((statp->options & RES_INIT) != 0U) 214 res_ndestroy(statp); 215 216 if (!preinit) { 217 statp->retrans = RES_TIMEOUT; 218 statp->retry = RES_DFLRETRY; 219 statp->options = RES_DEFAULT; 220 } 221 statp->_rnd = malloc(16); 222 res_rndinit(statp); 223 statp->id = res_nrandomid(statp); 224 225 memset(u, 0, sizeof(u)); 226 #ifdef USELOOPBACK 227 u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1); 228 #else 229 u[nserv].sin.sin_addr.s_addr = INADDR_ANY; 230 #endif 231 u[nserv].sin.sin_family = AF_INET; 232 u[nserv].sin.sin_port = htons(NAMESERVER_PORT); 233 #ifdef HAVE_SA_LEN 234 u[nserv].sin.sin_len = sizeof(struct sockaddr_in); 235 #endif 236 nserv++; 237 #ifdef HAS_INET6_STRUCTS 238 #ifdef USELOOPBACK 239 u[nserv].sin6.sin6_addr = in6addr_loopback; 240 #else 241 u[nserv].sin6.sin6_addr = in6addr_any; 242 #endif 243 u[nserv].sin6.sin6_family = AF_INET6; 244 u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT); 245 #ifdef HAVE_SA_LEN 246 u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6); 247 #endif 248 nserv++; 249 #endif 250 statp->nscount = 0; 251 statp->ndots = 1; 252 statp->pfcode = 0; 253 statp->_vcsock = -1; 254 statp->_flags = 0; 255 statp->qhook = NULL; 256 statp->rhook = NULL; 257 statp->_u._ext.nscount = 0; 258 statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext)); 259 if (statp->_u._ext.ext != NULL) { 260 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext)); 261 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr; 262 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa"); 263 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int"); 264 } else { 265 /* 266 * Historically res_init() rarely, if at all, failed. 267 * Examples and applications exist which do not check 268 * our return code. Furthermore several applications 269 * simply call us to get the systems domainname. So 270 * rather than immediately fail here we store the 271 * failure, which is returned later, in h_errno. And 272 * prevent the collection of 'nameserver' information 273 * by setting maxns to 0. Thus applications that fail 274 * to check our return code wont be able to make 275 * queries anyhow. 276 */ 277 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 278 maxns = 0; 279 } 280 #ifdef RESOLVSORT 281 statp->nsort = 0; 282 #endif 283 res_setservers(statp, u, nserv); 284 285 #ifdef SOLARIS2 286 /* 287 * The old libresolv derived the defaultdomain from NIS/NIS+. 288 * We want to keep this behaviour 289 */ 290 { 291 char buf[sizeof(statp->defdname)], *cp; 292 int ret; 293 294 if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 && 295 (unsigned int)ret <= sizeof(buf)) { 296 if (buf[0] == '+') 297 buf[0] = '.'; 298 cp = strchr(buf, '.'); 299 cp = (cp == NULL) ? buf : (cp + 1); 300 (void)strlcpy(statp->defdname, cp, 301 sizeof(statp->defdname)); 302 } 303 } 304 #endif /* SOLARIS2 */ 305 306 /* Allow user to override the local domain definition */ 307 if ((cp = getenv("LOCALDOMAIN")) != NULL) { 308 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 309 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 310 haveenv++; 311 312 /* 313 * Set search list to be blank-separated strings 314 * from rest of env value. Permits users of LOCALDOMAIN 315 * to still have a search list, and anyone to set the 316 * one that they want to use as an individual (even more 317 * important now that the rfc1535 stuff restricts searches) 318 */ 319 cp = statp->defdname; 320 pp = statp->dnsrch; 321 *pp++ = cp; 322 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) { 323 if (*cp == '\n') /*%< silly backwards compat */ 324 break; 325 else if (*cp == ' ' || *cp == '\t') { 326 *cp = 0; 327 n = 1; 328 } else if (n) { 329 *pp++ = cp; 330 n = 0; 331 havesearch = 1; 332 } 333 } 334 /* null terminate last domain if there are excess */ 335 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n') 336 cp++; 337 *cp = '\0'; 338 *pp++ = 0; 339 } 340 341 #define MATCH(line, name) \ 342 (!strncmp(line, name, sizeof(name) - 1) && \ 343 (line[sizeof(name) - 1] == ' ' || \ 344 line[sizeof(name) - 1] == '\t')) 345 346 nserv = 0; 347 if ((fp = fopen(__res_conf_name, "re")) != NULL) { 348 struct stat st; 349 struct kevent kc; 350 351 /* read the config file */ 352 while (fgets(buf, (int)sizeof(buf), fp) != NULL) { 353 /* skip comments */ 354 if (*buf == ';' || *buf == '#') 355 continue; 356 /* read default domain name */ 357 if (MATCH(buf, "domain")) { 358 if (haveenv) /*%< skip if have from environ */ 359 continue; 360 cp = buf + sizeof("domain") - 1; 361 while (*cp == ' ' || *cp == '\t') 362 cp++; 363 if ((*cp == '\0') || (*cp == '\n')) 364 continue; 365 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 366 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 367 if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL) 368 *cp = '\0'; 369 havesearch = 0; 370 continue; 371 } 372 /* set search list */ 373 if (MATCH(buf, "search")) { 374 if (haveenv) /*%< skip if have from environ */ 375 continue; 376 cp = buf + sizeof("search") - 1; 377 while (*cp == ' ' || *cp == '\t') 378 cp++; 379 if ((*cp == '\0') || (*cp == '\n')) 380 continue; 381 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 382 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 383 if ((cp = strchr(statp->defdname, '\n')) != NULL) 384 *cp = '\0'; 385 /* 386 * Set search list to be blank-separated strings 387 * on rest of line. 388 */ 389 cp = statp->defdname; 390 pp = statp->dnsrch; 391 *pp++ = cp; 392 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) { 393 if (*cp == ' ' || *cp == '\t') { 394 *cp = 0; 395 n = 1; 396 } else if (n) { 397 *pp++ = cp; 398 n = 0; 399 } 400 } 401 /* null terminate last domain if there are excess */ 402 while (*cp != '\0' && *cp != ' ' && *cp != '\t') 403 cp++; 404 *cp = '\0'; 405 *pp++ = 0; 406 havesearch = 1; 407 continue; 408 } 409 /* read nameservers to query */ 410 if (MATCH(buf, "nameserver") && nserv < maxns) { 411 struct addrinfo hints, *ai; 412 char sbuf[NI_MAXSERV]; 413 const size_t minsiz = 414 sizeof(statp->_u._ext.ext->nsaddrs[0]); 415 416 cp = buf + sizeof("nameserver") - 1; 417 while (*cp == ' ' || *cp == '\t') 418 cp++; 419 cp[strcspn(cp, ";# \t\n")] = '\0'; 420 if ((*cp != '\0') && (*cp != '\n')) { 421 memset(&hints, 0, sizeof(hints)); 422 hints.ai_family = PF_UNSPEC; 423 hints.ai_socktype = SOCK_DGRAM; /*dummy*/ 424 hints.ai_flags = AI_NUMERICHOST; 425 sprintf(sbuf, "%u", NAMESERVER_PORT); 426 if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 && 427 ai->ai_addrlen <= minsiz) { 428 if (statp->_u._ext.ext != NULL) { 429 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 430 ai->ai_addr, ai->ai_addrlen); 431 } 432 if (ai->ai_addrlen <= 433 sizeof(statp->nsaddr_list[nserv])) { 434 memcpy(&statp->nsaddr_list[nserv], 435 ai->ai_addr, ai->ai_addrlen); 436 } else 437 statp->nsaddr_list[nserv].sin_family = 0; 438 freeaddrinfo(ai); 439 nserv++; 440 } 441 } 442 continue; 443 } 444 #ifdef RESOLVSORT 445 if (MATCH(buf, "sortlist")) { 446 struct in_addr a; 447 448 cp = buf + sizeof("sortlist") - 1; 449 while (nsort < MAXRESOLVSORT) { 450 while (*cp == ' ' || *cp == '\t') 451 cp++; 452 if (*cp == '\0' || *cp == '\n' || *cp == ';') 453 break; 454 net = cp; 455 while (*cp && !ISSORTMASK(*cp) && *cp != ';' && 456 isascii(*cp) && !isspace((unsigned char)*cp)) 457 cp++; 458 n = *cp; 459 *cp = 0; 460 if (inet_aton(net, &a)) { 461 statp->sort_list[nsort].addr = a; 462 if (ISSORTMASK(n)) { 463 *cp++ = n; 464 net = cp; 465 while (*cp && *cp != ';' && 466 isascii(*cp) && 467 !isspace((unsigned char)*cp)) 468 cp++; 469 n = *cp; 470 *cp = 0; 471 if (inet_aton(net, &a)) { 472 statp->sort_list[nsort].mask = a.s_addr; 473 } else { 474 statp->sort_list[nsort].mask = 475 net_mask(statp->sort_list[nsort].addr); 476 } 477 } else { 478 statp->sort_list[nsort].mask = 479 net_mask(statp->sort_list[nsort].addr); 480 } 481 nsort++; 482 } 483 *cp = n; 484 } 485 continue; 486 } 487 #endif 488 if (MATCH(buf, "options")) { 489 res_setoptions(statp, buf + sizeof("options") - 1, "conf"); 490 continue; 491 } 492 } 493 if (nserv > 0) 494 statp->nscount = nserv; 495 #ifdef RESOLVSORT 496 statp->nsort = nsort; 497 #endif 498 statp->_u._ext.ext->resfd = fcntl(fileno(fp), F_DUPFD_CLOEXEC, 0); 499 (void) fclose(fp); 500 if (fstat(statp->_u._ext.ext->resfd, &st) != -1) 501 __res_conf_time = statp->_u._ext.ext->res_conf_time = 502 st.st_mtimespec; 503 statp->_u._ext.ext->kq = kqueue1(O_CLOEXEC); 504 EV_SET(&kc, statp->_u._ext.ext->resfd, EVFILT_VNODE, 505 EV_ADD|EV_ENABLE|EV_CLEAR, NOTE_DELETE|NOTE_WRITE| NOTE_EXTEND| 506 NOTE_ATTRIB|NOTE_LINK|NOTE_RENAME|NOTE_REVOKE, 0, 0); 507 (void)kevent(statp->_u._ext.ext->kq, &kc, 1, NULL, 0, &ts); 508 } else { 509 statp->_u._ext.ext->kq = -1; 510 statp->_u._ext.ext->resfd = -1; 511 } 512 /* 513 * Last chance to get a nameserver. This should not normally 514 * be necessary 515 */ 516 #ifdef NO_RESOLV_CONF 517 if(nserv == 0) 518 nserv = get_nameservers(statp); 519 #endif 520 521 if (statp->defdname[0] == 0 && 522 gethostname(buf, sizeof(statp->defdname) - 1) == 0 && 523 (cp = strchr(buf, '.')) != NULL) 524 strcpy(statp->defdname, cp + 1); 525 526 /* find components of local domain that might be searched */ 527 if (havesearch == 0) { 528 pp = statp->dnsrch; 529 *pp++ = statp->defdname; 530 *pp = NULL; 531 532 dots = 0; 533 for (cp = statp->defdname; *cp; cp++) 534 dots += (*cp == '.'); 535 536 cp = statp->defdname; 537 while (pp < statp->dnsrch + MAXDFLSRCH) { 538 if (dots < LOCALDOMAINPARTS) 539 break; 540 cp = strchr(cp, '.') + 1; /*%< we know there is one */ 541 *pp++ = cp; 542 dots--; 543 } 544 *pp = NULL; 545 #ifdef DEBUG 546 if (statp->options & RES_DEBUG) { 547 printf(";; res_init()... default dnsrch list:\n"); 548 for (pp = statp->dnsrch; *pp; pp++) 549 printf(";;\t%s\n", *pp); 550 printf(";;\t..END..\n"); 551 } 552 #endif 553 } 554 555 if ((cp = getenv("RES_OPTIONS")) != NULL) 556 res_setoptions(statp, cp, "env"); 557 statp->options |= RES_INIT; 558 return (statp->res_h_errno); 559 } 560 561 int 562 res_check(res_state statp, struct timespec *mtime) 563 { 564 /* 565 * If the times are equal, then we check if there 566 * was a kevent related to resolv.conf and reload. 567 * If the times are not equal, then we don't bother 568 * to check the kevent, because another thread already 569 * did, loaded and changed the time. 570 */ 571 if (timespeccmp(&statp->_u._ext.ext->res_conf_time, 572 &__res_conf_time, ==)) { 573 struct kevent ke; 574 if (statp->_u._ext.ext->kq == -1) 575 goto out; 576 577 switch (kevent(statp->_u._ext.ext->kq, NULL, 0, &ke, 1, &ts)) { 578 case 0: 579 case -1: 580 out: 581 if (mtime) 582 *mtime = __res_conf_time; 583 return 0; 584 default: 585 break; 586 } 587 } 588 (void)__res_vinit(statp, 0); 589 if (mtime) 590 *mtime = __res_conf_time; 591 return 1; 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 size_t j; 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, "rotate", sizeof("rotate") - 1)) { 675 statp->options |= RES_ROTATE; 676 } else if (!strncmp(cp, "no-check-names", 677 sizeof("no-check-names") - 1)) { 678 statp->options |= RES_NOCHECKNAME; 679 } else if (!strncmp(cp, "check-names", 680 sizeof("check-names") - 1)) { 681 statp->options &= ~RES_NOCHECKNAME; 682 } 683 #ifdef RES_USE_EDNS0 684 else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) { 685 statp->options |= RES_USE_EDNS0; 686 } 687 #endif 688 else if (!strncmp(cp, "dname", sizeof("dname") - 1)) { 689 statp->options |= RES_USE_DNAME; 690 } 691 else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) { 692 if (ext == NULL) 693 goto skip; 694 cp += sizeof("nibble:") - 1; 695 j = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1); 696 strncpy(ext->nsuffix, cp, j); 697 ext->nsuffix[j] = '\0'; 698 } 699 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) { 700 if (ext == NULL) 701 goto skip; 702 cp += sizeof("nibble2:") - 1; 703 j = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1); 704 strncpy(ext->nsuffix2, cp, j); 705 ext->nsuffix2[j] = '\0'; 706 } 707 else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) { 708 cp += sizeof("v6revmode:") - 1; 709 /* "nibble" and "bitstring" used to be valid */ 710 if (!strncmp(cp, "single", sizeof("single") - 1)) { 711 statp->options |= RES_NO_NIBBLE2; 712 } else if (!strncmp(cp, "both", sizeof("both") - 1)) { 713 statp->options &= 714 ~RES_NO_NIBBLE2; 715 } 716 } 717 else { 718 /* XXX - print a warning here? */ 719 } 720 skip: 721 /* skip to next run of spaces */ 722 while (*cp && *cp != ' ' && *cp != '\t') 723 cp++; 724 } 725 } 726 727 #ifdef RESOLVSORT 728 /* XXX - should really support CIDR which means explicit masks always. */ 729 static uint32_t 730 net_mask(struct in_addr in) /*!< XXX - should really use system's version of this */ 731 { 732 register uint32_t i = ntohl(in.s_addr); 733 734 if (IN_CLASSA(i)) 735 return (htonl(IN_CLASSA_NET)); 736 else if (IN_CLASSB(i)) 737 return (htonl(IN_CLASSB_NET)); 738 return (htonl(IN_CLASSC_NET)); 739 } 740 #endif 741 742 static u_char srnd[16]; 743 744 void 745 res_rndinit(res_state statp) 746 { 747 struct timeval now; 748 uint32_t u32; 749 uint16_t u16; 750 u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd; 751 752 gettimeofday(&now, NULL); 753 u32 = (uint32_t)now.tv_sec; 754 memcpy(rnd, &u32, 4); 755 u32 = now.tv_usec; 756 memcpy(rnd + 4, &u32, 4); 757 u32 += (uint32_t)now.tv_sec; 758 memcpy(rnd + 8, &u32, 4); 759 u16 = getpid(); 760 memcpy(rnd + 12, &u16, 2); 761 } 762 763 u_int 764 res_nrandomid(res_state statp) 765 { 766 struct timeval now; 767 uint16_t u16; 768 MD5_CTX ctx; 769 u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd; 770 771 gettimeofday(&now, NULL); 772 u16 = (uint16_t) (now.tv_sec ^ now.tv_usec); 773 memcpy(rnd + 14, &u16, 2); 774 #ifndef HAVE_MD5 775 MD5_Init(&ctx); 776 MD5_Update(&ctx, rnd, 16); 777 MD5_Final(rnd, &ctx); 778 #else 779 MD5Init(&ctx); 780 MD5Update(&ctx, rnd, 16); 781 MD5Final(rnd, &ctx); 782 #endif 783 memcpy(&u16, rnd + 14, 2); 784 return ((u_int) u16); 785 } 786 787 /*% 788 * This routine is for closing the socket if a virtual circuit is used and 789 * the program wants to close it. This provides support for endhostent() 790 * which expects to close the socket. 791 * 792 * This routine is not expected to be user visible. 793 */ 794 void 795 res_nclose(res_state statp) 796 { 797 int ns; 798 799 if (statp->_vcsock >= 0) { 800 (void) close(statp->_vcsock); 801 statp->_vcsock = -1; 802 statp->_flags &= ~(RES_F_VC | RES_F_CONN); 803 } 804 for (ns = 0; ns < statp->_u._ext.nscount; ns++) { 805 if (statp->_u._ext.nssocks[ns] != -1) { 806 (void) close(statp->_u._ext.nssocks[ns]); 807 statp->_u._ext.nssocks[ns] = -1; 808 } 809 } 810 } 811 812 void 813 res_ndestroy(res_state statp) 814 { 815 res_nclose(statp); 816 if (statp->_u._ext.ext != NULL) { 817 if (statp->_u._ext.ext->kq != -1) 818 (void)close(statp->_u._ext.ext->kq); 819 if (statp->_u._ext.ext->resfd != -1) 820 (void)close(statp->_u._ext.ext->resfd); 821 free(statp->_u._ext.ext); 822 statp->_u._ext.ext = NULL; 823 } 824 if (statp->_rnd != NULL) { 825 free(statp->_rnd); 826 statp->_rnd = NULL; 827 } 828 statp->options &= ~RES_INIT; 829 } 830 831 const char * 832 res_get_nibblesuffix(res_state statp) 833 { 834 if (statp->_u._ext.ext) 835 return (statp->_u._ext.ext->nsuffix); 836 return ("ip6.arpa"); 837 } 838 839 const char * 840 res_get_nibblesuffix2(res_state statp) 841 { 842 if (statp->_u._ext.ext) 843 return (statp->_u._ext.ext->nsuffix2); 844 return ("ip6.int"); 845 } 846 847 void 848 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) 849 { 850 int i, nserv; 851 size_t size; 852 853 /* close open servers */ 854 res_nclose(statp); 855 856 /* cause rtt times to be forgotten */ 857 statp->_u._ext.nscount = 0; 858 859 nserv = 0; 860 for (i = 0; i < cnt && nserv < MAXNS; i++) { 861 switch (set->sin.sin_family) { 862 case AF_INET: 863 size = sizeof(set->sin); 864 if (statp->_u._ext.ext) 865 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 866 &set->sin, size); 867 if (size <= sizeof(statp->nsaddr_list[nserv])) 868 memcpy(&statp->nsaddr_list[nserv], 869 &set->sin, size); 870 else 871 statp->nsaddr_list[nserv].sin_family = 0; 872 nserv++; 873 break; 874 875 #ifdef HAS_INET6_STRUCTS 876 case AF_INET6: 877 size = sizeof(set->sin6); 878 if (statp->_u._ext.ext) 879 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 880 &set->sin6, size); 881 if (size <= sizeof(statp->nsaddr_list[nserv])) 882 memcpy(&statp->nsaddr_list[nserv], 883 &set->sin6, size); 884 else 885 statp->nsaddr_list[nserv].sin_family = 0; 886 nserv++; 887 break; 888 #endif 889 890 default: 891 break; 892 } 893 set++; 894 } 895 statp->nscount = nserv; 896 897 } 898 899 int 900 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) 901 { 902 int i; 903 size_t size; 904 uint16_t family; 905 906 for (i = 0; i < statp->nscount && i < cnt; i++) { 907 if (statp->_u._ext.ext) 908 family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family; 909 else 910 family = statp->nsaddr_list[i].sin_family; 911 912 switch (family) { 913 case AF_INET: 914 size = sizeof(set->sin); 915 if (statp->_u._ext.ext) 916 memcpy(&set->sin, 917 &statp->_u._ext.ext->nsaddrs[i], 918 size); 919 else 920 memcpy(&set->sin, &statp->nsaddr_list[i], 921 size); 922 break; 923 924 #ifdef HAS_INET6_STRUCTS 925 case AF_INET6: 926 size = sizeof(set->sin6); 927 if (statp->_u._ext.ext) 928 memcpy(&set->sin6, 929 &statp->_u._ext.ext->nsaddrs[i], 930 size); 931 else 932 memcpy(&set->sin6, &statp->nsaddr_list[i], 933 size); 934 break; 935 #endif 936 937 default: 938 set->sin.sin_family = 0; 939 break; 940 } 941 set++; 942 } 943 return (statp->nscount); 944 } 945 946 /*! \file */ 947