1 /* $NetBSD: res_init.c,v 1.22 2009/10/24 17:24:01 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 1.26 2008/12/11 09:59:00 marka Exp"; 78 #else 79 __RCSID("$NetBSD: res_init.c,v 1.22 2009/10/24 17:24:01 christos Exp $"); 80 #endif 81 #endif /* LIBC_SCCS and not lint */ 82 83 #include "port_before.h" 84 85 #include "namespace.h" 86 #include <sys/types.h> 87 #include <sys/param.h> 88 #include <sys/socket.h> 89 #include <sys/stat.h> 90 #include <sys/time.h> 91 #include <sys/event.h> 92 93 #include <netinet/in.h> 94 #include <arpa/inet.h> 95 #include <arpa/nameser.h> 96 97 #include <ctype.h> 98 #include <stdio.h> 99 #include <stdlib.h> 100 #include <string.h> 101 #include <unistd.h> 102 #include <fcntl.h> 103 #include <netdb.h> 104 105 #define HAVE_MD5 106 #include <md5.h> 107 108 #ifndef HAVE_MD5 109 # include "../dst/md5.h" 110 #else 111 # ifdef SOLARIS2 112 # include <sys/md5.h> 113 # endif 114 #endif 115 #ifndef _MD5_H_ 116 # define _MD5_H_ 1 /*%< make sure we do not include rsaref md5.h file */ 117 #endif 118 119 #include "port_after.h" 120 121 #if 0 122 #ifdef __weak_alias 123 __weak_alias(res_ninit,_res_ninit) 124 __weak_alias(res_randomid,__res_randomid) 125 __weak_alias(res_nclose,_res_nclose) 126 __weak_alias(res_ndestroy,_res_ndestroy) 127 __weak_alias(res_get_nibblesuffix,__res_get_nibblesuffix) 128 __weak_alias(res_get_nibblesuffix2,__res_get_nibblesuffix2) 129 __weak_alias(res_getservers,__res_getservers) 130 __weak_alias(res_setservers,__res_setservers) 131 #endif 132 #endif 133 134 135 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */ 136 #include <resolv.h> 137 138 #include "res_private.h" 139 140 #define RESOLVSORT 141 /*% Options. Should all be left alone. */ 142 #ifndef DEBUG 143 #define DEBUG 144 #endif 145 146 #ifdef SOLARIS2 147 #include <sys/systeminfo.h> 148 #endif 149 150 static void res_setoptions __P((res_state, const char *, const char *)); 151 152 #ifdef RESOLVSORT 153 static const char sort_mask[] = "/&"; 154 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL) 155 static u_int32_t net_mask __P((struct in_addr)); 156 #endif 157 158 #if !defined(isascii) /*%< XXX - could be a function */ 159 # define isascii(c) (!(c & 0200)) 160 #endif 161 162 static struct timespec __res_conf_time; 163 static const struct timespec ts = { 0, 0 }; 164 165 /* 166 * Resolver state default settings. 167 */ 168 169 /*% 170 * Set up default settings. If the configuration file exist, the values 171 * there will have precedence. Otherwise, the server address is set to 172 * INADDR_ANY and the default domain name comes from the gethostname(). 173 * 174 * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1 175 * rather than INADDR_ANY ("0.0.0.0") as the default name server address 176 * since it was noted that INADDR_ANY actually meant ``the first interface 177 * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface, 178 * it had to be "up" in order for you to reach your own name server. It 179 * was later decided that since the recommended practice is to always 180 * install local static routes through 127.0.0.1 for all your network 181 * interfaces, that we could solve this problem without a code change. 182 * 183 * The configuration file should always be used, since it is the only way 184 * to specify a default domain. If you are running a server on your local 185 * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1" 186 * in the configuration file. 187 * 188 * Return 0 if completes successfully, -1 on error 189 */ 190 int 191 res_ninit(res_state statp) { 192 return (__res_vinit(statp, 0)); 193 } 194 195 /*% This function has to be reachable by res_data.c but not publically. */ 196 int 197 __res_vinit(res_state statp, int preinit) { 198 register FILE *fp; 199 register char *cp, **pp; 200 register int n; 201 char buf[BUFSIZ]; 202 int nserv = 0; /*%< number of nameserver records read from file */ 203 int haveenv = 0; 204 int havesearch = 0; 205 #ifdef RESOLVSORT 206 int nsort = 0; 207 char *net; 208 #endif 209 int dots; 210 union res_sockaddr_union u[2]; 211 int maxns = MAXNS; 212 213 RES_SET_H_ERRNO(statp, 0); 214 215 if ((statp->options & RES_INIT) != 0U) 216 res_ndestroy(statp); 217 218 if (!preinit) { 219 statp->retrans = RES_TIMEOUT; 220 statp->retry = RES_DFLRETRY; 221 statp->options = RES_DEFAULT; 222 } 223 statp->_rnd = malloc(16); 224 res_rndinit(statp); 225 statp->id = res_nrandomid(statp); 226 227 memset(u, 0, sizeof(u)); 228 #ifdef USELOOPBACK 229 u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1); 230 #else 231 u[nserv].sin.sin_addr.s_addr = INADDR_ANY; 232 #endif 233 u[nserv].sin.sin_family = AF_INET; 234 u[nserv].sin.sin_port = htons(NAMESERVER_PORT); 235 #ifdef HAVE_SA_LEN 236 u[nserv].sin.sin_len = sizeof(struct sockaddr_in); 237 #endif 238 nserv++; 239 #ifdef HAS_INET6_STRUCTS 240 #ifdef USELOOPBACK 241 u[nserv].sin6.sin6_addr = in6addr_loopback; 242 #else 243 u[nserv].sin6.sin6_addr = in6addr_any; 244 #endif 245 u[nserv].sin6.sin6_family = AF_INET6; 246 u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT); 247 #ifdef HAVE_SA_LEN 248 u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6); 249 #endif 250 nserv++; 251 #endif 252 statp->nscount = 0; 253 statp->ndots = 1; 254 statp->pfcode = 0; 255 statp->_vcsock = -1; 256 statp->_flags = 0; 257 statp->qhook = NULL; 258 statp->rhook = NULL; 259 statp->_u._ext.nscount = 0; 260 statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext)); 261 if (statp->_u._ext.ext != NULL) { 262 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext)); 263 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr; 264 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa"); 265 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int"); 266 } else { 267 /* 268 * Historically res_init() rarely, if at all, failed. 269 * Examples and applications exist which do not check 270 * our return code. Furthermore several applications 271 * simply call us to get the systems domainname. So 272 * rather then immediately fail here we store the 273 * failure, which is returned later, in h_errno. And 274 * prevent the collection of 'nameserver' information 275 * by setting maxns to 0. Thus applications that fail 276 * to check our return code wont be able to make 277 * queries anyhow. 278 */ 279 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 280 maxns = 0; 281 } 282 #ifdef RESOLVSORT 283 statp->nsort = 0; 284 #endif 285 res_setservers(statp, u, nserv); 286 287 #ifdef SOLARIS2 288 /* 289 * The old libresolv derived the defaultdomain from NIS/NIS+. 290 * We want to keep this behaviour 291 */ 292 { 293 char buf[sizeof(statp->defdname)], *cp; 294 int ret; 295 296 if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 && 297 (unsigned int)ret <= sizeof(buf)) { 298 if (buf[0] == '+') 299 buf[0] = '.'; 300 cp = strchr(buf, '.'); 301 cp = (cp == NULL) ? buf : (cp + 1); 302 (void)strlcpy(statp->defdname, cp, 303 sizeof(statp->defdname)); 304 } 305 } 306 #endif /* SOLARIS2 */ 307 308 /* Allow user to override the local domain definition */ 309 if ((cp = getenv("LOCALDOMAIN")) != NULL) { 310 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 311 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 312 haveenv++; 313 314 /* 315 * Set search list to be blank-separated strings 316 * from rest of env value. Permits users of LOCALDOMAIN 317 * to still have a search list, and anyone to set the 318 * one that they want to use as an individual (even more 319 * important now that the rfc1535 stuff restricts searches) 320 */ 321 cp = statp->defdname; 322 pp = statp->dnsrch; 323 *pp++ = cp; 324 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) { 325 if (*cp == '\n') /*%< silly backwards compat */ 326 break; 327 else if (*cp == ' ' || *cp == '\t') { 328 *cp = 0; 329 n = 1; 330 } else if (n) { 331 *pp++ = cp; 332 n = 0; 333 havesearch = 1; 334 } 335 } 336 /* null terminate last domain if there are excess */ 337 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n') 338 cp++; 339 *cp = '\0'; 340 *pp++ = 0; 341 } 342 343 #define MATCH(line, name) \ 344 (!strncmp(line, name, sizeof(name) - 1) && \ 345 (line[sizeof(name) - 1] == ' ' || \ 346 line[sizeof(name) - 1] == '\t')) 347 348 nserv = 0; 349 if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) { 350 struct stat st; 351 struct kevent kc; 352 353 /* read the config file */ 354 while (fgets(buf, sizeof(buf), fp) != NULL) { 355 /* skip comments */ 356 if (*buf == ';' || *buf == '#') 357 continue; 358 /* read default domain name */ 359 if (MATCH(buf, "domain")) { 360 if (haveenv) /*%< skip if have from environ */ 361 continue; 362 cp = buf + sizeof("domain") - 1; 363 while (*cp == ' ' || *cp == '\t') 364 cp++; 365 if ((*cp == '\0') || (*cp == '\n')) 366 continue; 367 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 368 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 369 if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL) 370 *cp = '\0'; 371 havesearch = 0; 372 continue; 373 } 374 /* set search list */ 375 if (MATCH(buf, "search")) { 376 if (haveenv) /*%< skip if have from environ */ 377 continue; 378 cp = buf + sizeof("search") - 1; 379 while (*cp == ' ' || *cp == '\t') 380 cp++; 381 if ((*cp == '\0') || (*cp == '\n')) 382 continue; 383 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 384 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 385 if ((cp = strchr(statp->defdname, '\n')) != NULL) 386 *cp = '\0'; 387 /* 388 * Set search list to be blank-separated strings 389 * on rest of line. 390 */ 391 cp = statp->defdname; 392 pp = statp->dnsrch; 393 *pp++ = cp; 394 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) { 395 if (*cp == ' ' || *cp == '\t') { 396 *cp = 0; 397 n = 1; 398 } else if (n) { 399 *pp++ = cp; 400 n = 0; 401 } 402 } 403 /* null terminate last domain if there are excess */ 404 while (*cp != '\0' && *cp != ' ' && *cp != '\t') 405 cp++; 406 *cp = '\0'; 407 *pp++ = 0; 408 havesearch = 1; 409 continue; 410 } 411 /* read nameservers to query */ 412 if (MATCH(buf, "nameserver") && nserv < maxns) { 413 struct addrinfo hints, *ai; 414 char sbuf[NI_MAXSERV]; 415 const size_t minsiz = 416 sizeof(statp->_u._ext.ext->nsaddrs[0]); 417 418 cp = buf + sizeof("nameserver") - 1; 419 while (*cp == ' ' || *cp == '\t') 420 cp++; 421 cp[strcspn(cp, ";# \t\n")] = '\0'; 422 if ((*cp != '\0') && (*cp != '\n')) { 423 memset(&hints, 0, sizeof(hints)); 424 hints.ai_family = PF_UNSPEC; 425 hints.ai_socktype = SOCK_DGRAM; /*dummy*/ 426 hints.ai_flags = AI_NUMERICHOST; 427 sprintf(sbuf, "%u", NAMESERVER_PORT); 428 if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 && 429 ai->ai_addrlen <= minsiz) { 430 if (statp->_u._ext.ext != NULL) { 431 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 432 ai->ai_addr, ai->ai_addrlen); 433 } 434 if (ai->ai_addrlen <= 435 sizeof(statp->nsaddr_list[nserv])) { 436 memcpy(&statp->nsaddr_list[nserv], 437 ai->ai_addr, ai->ai_addrlen); 438 } else 439 statp->nsaddr_list[nserv].sin_family = 0; 440 freeaddrinfo(ai); 441 nserv++; 442 } 443 } 444 continue; 445 } 446 #ifdef RESOLVSORT 447 if (MATCH(buf, "sortlist")) { 448 struct in_addr a; 449 450 cp = buf + sizeof("sortlist") - 1; 451 while (nsort < MAXRESOLVSORT) { 452 while (*cp == ' ' || *cp == '\t') 453 cp++; 454 if (*cp == '\0' || *cp == '\n' || *cp == ';') 455 break; 456 net = cp; 457 while (*cp && !ISSORTMASK(*cp) && *cp != ';' && 458 isascii(*cp) && !isspace((unsigned char)*cp)) 459 cp++; 460 n = *cp; 461 *cp = 0; 462 if (inet_aton(net, &a)) { 463 statp->sort_list[nsort].addr = a; 464 if (ISSORTMASK(n)) { 465 *cp++ = n; 466 net = cp; 467 while (*cp && *cp != ';' && 468 isascii(*cp) && 469 !isspace((unsigned char)*cp)) 470 cp++; 471 n = *cp; 472 *cp = 0; 473 if (inet_aton(net, &a)) { 474 statp->sort_list[nsort].mask = a.s_addr; 475 } else { 476 statp->sort_list[nsort].mask = 477 net_mask(statp->sort_list[nsort].addr); 478 } 479 } else { 480 statp->sort_list[nsort].mask = 481 net_mask(statp->sort_list[nsort].addr); 482 } 483 nsort++; 484 } 485 *cp = n; 486 } 487 continue; 488 } 489 #endif 490 if (MATCH(buf, "options")) { 491 res_setoptions(statp, buf + sizeof("options") - 1, "conf"); 492 continue; 493 } 494 } 495 if (nserv > 0) 496 statp->nscount = nserv; 497 #ifdef RESOLVSORT 498 statp->nsort = nsort; 499 #endif 500 statp->_u._ext.ext->resfd = dup(fileno(fp)); 501 (void) fclose(fp); 502 if (fstat(statp->_u._ext.ext->resfd, &st) != -1) 503 __res_conf_time = statp->_u._ext.ext->res_conf_time = 504 st.st_mtimespec; 505 statp->_u._ext.ext->kq = kqueue(); 506 (void)fcntl(statp->_u._ext.ext->kq, F_SETFD, FD_CLOEXEC); 507 (void)fcntl(statp->_u._ext.ext->resfd, F_SETFD, FD_CLOEXEC); 508 EV_SET(&kc, statp->_u._ext.ext->resfd, EVFILT_VNODE, 509 EV_ADD|EV_ENABLE|EV_CLEAR, NOTE_DELETE|NOTE_WRITE| NOTE_EXTEND| 510 NOTE_ATTRIB|NOTE_LINK|NOTE_RENAME|NOTE_REVOKE, 0, 0); 511 (void)kevent(statp->_u._ext.ext->kq, &kc, 1, NULL, 0, &ts); 512 } else { 513 statp->_u._ext.ext->kq = -1; 514 statp->_u._ext.ext->resfd = -1; 515 } 516 /* 517 * Last chance to get a nameserver. This should not normally 518 * be necessary 519 */ 520 #ifdef NO_RESOLV_CONF 521 if(nserv == 0) 522 nserv = get_nameservers(statp); 523 #endif 524 525 if (statp->defdname[0] == 0 && 526 gethostname(buf, sizeof(statp->defdname) - 1) == 0 && 527 (cp = strchr(buf, '.')) != NULL) 528 strcpy(statp->defdname, cp + 1); 529 530 /* find components of local domain that might be searched */ 531 if (havesearch == 0) { 532 pp = statp->dnsrch; 533 *pp++ = statp->defdname; 534 *pp = NULL; 535 536 dots = 0; 537 for (cp = statp->defdname; *cp; cp++) 538 dots += (*cp == '.'); 539 540 cp = statp->defdname; 541 while (pp < statp->dnsrch + MAXDFLSRCH) { 542 if (dots < LOCALDOMAINPARTS) 543 break; 544 cp = strchr(cp, '.') + 1; /*%< we know there is one */ 545 *pp++ = cp; 546 dots--; 547 } 548 *pp = NULL; 549 #ifdef DEBUG 550 if (statp->options & RES_DEBUG) { 551 printf(";; res_init()... default dnsrch list:\n"); 552 for (pp = statp->dnsrch; *pp; pp++) 553 printf(";;\t%s\n", *pp); 554 printf(";;\t..END..\n"); 555 } 556 #endif 557 } 558 559 if ((cp = getenv("RES_OPTIONS")) != NULL) 560 res_setoptions(statp, cp, "env"); 561 statp->options |= RES_INIT; 562 return (statp->res_h_errno); 563 } 564 565 int 566 res_check(res_state statp, struct timespec *mtime) 567 { 568 /* 569 * If the times are equal, then we check if there 570 * was a kevent related to resolv.conf and reload. 571 * If the times are not equal, then we don't bother 572 * to check the kevent, because another thread already 573 * did, loaded and changed the time. 574 */ 575 if (timespeccmp(&statp->_u._ext.ext->res_conf_time, 576 &__res_conf_time, ==)) { 577 struct kevent ke; 578 if (statp->_u._ext.ext->kq == -1) 579 goto out; 580 581 switch (kevent(statp->_u._ext.ext->kq, NULL, 0, &ke, 1, &ts)) { 582 case 0: 583 case -1: 584 out: 585 if (mtime) 586 *mtime = __res_conf_time; 587 return 0; 588 default: 589 break; 590 } 591 } 592 (void)__res_vinit(statp, 0); 593 if (mtime) 594 *mtime = __res_conf_time; 595 return 1; 596 } 597 598 static void 599 res_setoptions(res_state statp, const char *options, const char *source) 600 { 601 const char *cp = options; 602 int i; 603 struct __res_state_ext *ext = statp->_u._ext.ext; 604 605 #ifdef DEBUG 606 if (statp->options & RES_DEBUG) 607 printf(";; res_setoptions(\"%s\", \"%s\")...\n", 608 options, source); 609 #endif 610 while (*cp) { 611 /* skip leading and inner runs of spaces */ 612 while (*cp == ' ' || *cp == '\t') 613 cp++; 614 /* search for and process individual options */ 615 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) { 616 i = atoi(cp + sizeof("ndots:") - 1); 617 if (i <= RES_MAXNDOTS) 618 statp->ndots = i; 619 else 620 statp->ndots = RES_MAXNDOTS; 621 #ifdef DEBUG 622 if (statp->options & RES_DEBUG) 623 printf(";;\tndots=%d\n", statp->ndots); 624 #endif 625 } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) { 626 i = atoi(cp + sizeof("timeout:") - 1); 627 if (i <= RES_MAXRETRANS) 628 statp->retrans = i; 629 else 630 statp->retrans = RES_MAXRETRANS; 631 #ifdef DEBUG 632 if (statp->options & RES_DEBUG) 633 printf(";;\ttimeout=%d\n", statp->retrans); 634 #endif 635 #ifdef SOLARIS2 636 } else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) { 637 /* 638 * For backward compatibility, 'retrans' is 639 * supported as an alias for 'timeout', though 640 * without an imposed maximum. 641 */ 642 statp->retrans = atoi(cp + sizeof("retrans:") - 1); 643 } else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){ 644 /* 645 * For backward compatibility, 'retry' is 646 * supported as an alias for 'attempts', though 647 * without an imposed maximum. 648 */ 649 statp->retry = atoi(cp + sizeof("retry:") - 1); 650 #endif /* SOLARIS2 */ 651 } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){ 652 i = atoi(cp + sizeof("attempts:") - 1); 653 if (i <= RES_MAXRETRY) 654 statp->retry = i; 655 else 656 statp->retry = RES_MAXRETRY; 657 #ifdef DEBUG 658 if (statp->options & RES_DEBUG) 659 printf(";;\tattempts=%d\n", statp->retry); 660 #endif 661 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) { 662 #ifdef DEBUG 663 if (!(statp->options & RES_DEBUG)) { 664 printf(";; res_setoptions(\"%s\", \"%s\")..\n", 665 options, source); 666 statp->options |= RES_DEBUG; 667 } 668 printf(";;\tdebug\n"); 669 #endif 670 } else if (!strncmp(cp, "no_tld_query", 671 sizeof("no_tld_query") - 1) || 672 !strncmp(cp, "no-tld-query", 673 sizeof("no-tld-query") - 1)) { 674 statp->options |= RES_NOTLDQUERY; 675 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) { 676 statp->options |= RES_USE_INET6; 677 } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) { 678 statp->options |= RES_ROTATE; 679 } else if (!strncmp(cp, "no-check-names", 680 sizeof("no-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 i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1); 696 strncpy(ext->nsuffix, cp, (size_t)i); 697 ext->nsuffix[i] = '\0'; 698 } 699 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) { 700 if (ext == NULL) 701 goto skip; 702 cp += sizeof("nibble2:") - 1; 703 i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1); 704 strncpy(ext->nsuffix2, cp, (size_t)i); 705 ext->nsuffix2[i] = '\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 u_int32_t 730 net_mask(in) /*!< XXX - should really use system's version of this */ 731 struct in_addr in; 732 { 733 register u_int32_t i = ntohl(in.s_addr); 734 735 if (IN_CLASSA(i)) 736 return (htonl(IN_CLASSA_NET)); 737 else if (IN_CLASSB(i)) 738 return (htonl(IN_CLASSB_NET)); 739 return (htonl(IN_CLASSC_NET)); 740 } 741 #endif 742 743 static u_char srnd[16]; 744 745 void 746 res_rndinit(res_state statp) 747 { 748 struct timeval now; 749 u_int32_t u32; 750 u_int16_t u16; 751 u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd; 752 753 gettimeofday(&now, NULL); 754 u32 = (u_int32_t)now.tv_sec; 755 memcpy(rnd, &u32, 4); 756 u32 = now.tv_usec; 757 memcpy(rnd + 4, &u32, 4); 758 u32 += (u_int32_t)now.tv_sec; 759 memcpy(rnd + 8, &u32, 4); 760 u16 = getpid(); 761 memcpy(rnd + 12, &u16, 2); 762 } 763 764 u_int 765 res_nrandomid(res_state statp) { 766 struct timeval now; 767 u_int16_t u16; 768 MD5_CTX ctx; 769 u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd; 770 771 gettimeofday(&now, NULL); 772 u16 = (u_int16_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 int ns; 797 798 if (statp->_vcsock >= 0) { 799 (void) close(statp->_vcsock); 800 statp->_vcsock = -1; 801 statp->_flags &= ~(RES_F_VC | RES_F_CONN); 802 } 803 for (ns = 0; ns < statp->_u._ext.nscount; ns++) { 804 if (statp->_u._ext.nssocks[ns] != -1) { 805 (void) close(statp->_u._ext.nssocks[ns]); 806 statp->_u._ext.nssocks[ns] = -1; 807 } 808 } 809 } 810 811 void 812 res_ndestroy(res_state statp) { 813 res_nclose(statp); 814 if (statp->_u._ext.ext != NULL) { 815 if (statp->_u._ext.ext->kq != -1) 816 (void)close(statp->_u._ext.ext->kq); 817 if (statp->_u._ext.ext->resfd != -1) 818 (void)close(statp->_u._ext.ext->resfd); 819 free(statp->_u._ext.ext); 820 statp->_u._ext.ext = NULL; 821 } 822 if (statp->_rnd != NULL) { 823 free(statp->_rnd); 824 statp->_rnd = NULL; 825 } 826 statp->options &= ~RES_INIT; 827 } 828 829 const char * 830 res_get_nibblesuffix(res_state statp) { 831 if (statp->_u._ext.ext) 832 return (statp->_u._ext.ext->nsuffix); 833 return ("ip6.arpa"); 834 } 835 836 const char * 837 res_get_nibblesuffix2(res_state statp) { 838 if (statp->_u._ext.ext) 839 return (statp->_u._ext.ext->nsuffix2); 840 return ("ip6.int"); 841 } 842 843 void 844 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) { 845 int i, nserv; 846 size_t size; 847 848 /* close open servers */ 849 res_nclose(statp); 850 851 /* cause rtt times to be forgotten */ 852 statp->_u._ext.nscount = 0; 853 854 nserv = 0; 855 for (i = 0; i < cnt && nserv < MAXNS; i++) { 856 switch (set->sin.sin_family) { 857 case AF_INET: 858 size = sizeof(set->sin); 859 if (statp->_u._ext.ext) 860 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 861 &set->sin, size); 862 if (size <= sizeof(statp->nsaddr_list[nserv])) 863 memcpy(&statp->nsaddr_list[nserv], 864 &set->sin, size); 865 else 866 statp->nsaddr_list[nserv].sin_family = 0; 867 nserv++; 868 break; 869 870 #ifdef HAS_INET6_STRUCTS 871 case AF_INET6: 872 size = sizeof(set->sin6); 873 if (statp->_u._ext.ext) 874 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 875 &set->sin6, size); 876 if (size <= sizeof(statp->nsaddr_list[nserv])) 877 memcpy(&statp->nsaddr_list[nserv], 878 &set->sin6, size); 879 else 880 statp->nsaddr_list[nserv].sin_family = 0; 881 nserv++; 882 break; 883 #endif 884 885 default: 886 break; 887 } 888 set++; 889 } 890 statp->nscount = nserv; 891 892 } 893 894 int 895 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) { 896 int i; 897 size_t size; 898 u_int16_t family; 899 900 for (i = 0; i < statp->nscount && i < cnt; i++) { 901 if (statp->_u._ext.ext) 902 family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family; 903 else 904 family = statp->nsaddr_list[i].sin_family; 905 906 switch (family) { 907 case AF_INET: 908 size = sizeof(set->sin); 909 if (statp->_u._ext.ext) 910 memcpy(&set->sin, 911 &statp->_u._ext.ext->nsaddrs[i], 912 size); 913 else 914 memcpy(&set->sin, &statp->nsaddr_list[i], 915 size); 916 break; 917 918 #ifdef HAS_INET6_STRUCTS 919 case AF_INET6: 920 size = sizeof(set->sin6); 921 if (statp->_u._ext.ext) 922 memcpy(&set->sin6, 923 &statp->_u._ext.ext->nsaddrs[i], 924 size); 925 else 926 memcpy(&set->sin6, &statp->nsaddr_list[i], 927 size); 928 break; 929 #endif 930 931 default: 932 set->sin.sin_family = 0; 933 break; 934 } 935 set++; 936 } 937 return (statp->nscount); 938 } 939 940 /*! \file */ 941