res_init.c revision 1.32
1 /* $NetBSD: res_init.c,v 1.32 2021/09/30 12:35:55 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 1.32 2021/09/30 12:35:55 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 static int 194 __res_kqinit(res_state statp) 195 { 196 struct kevent kc; 197 struct __res_state_ext *ext = statp->_u._ext.ext; 198 199 ext->kq = kqueue1(O_CLOEXEC); 200 ext->kqpid = getpid(); 201 EV_SET(&kc, ext->resfd, EVFILT_VNODE, 202 EV_ADD|EV_ENABLE|EV_CLEAR, NOTE_DELETE|NOTE_WRITE| NOTE_EXTEND| 203 NOTE_ATTRIB|NOTE_LINK|NOTE_RENAME|NOTE_REVOKE, 0, 0); 204 (void)kevent(ext->kq, &kc, 1, NULL, 0, &ts); 205 return ext->kq; 206 } 207 208 /*% This function has to be reachable by res_data.c but not publically. */ 209 int 210 __res_vinit(res_state statp, int preinit) { 211 register FILE *fp; 212 register char *cp, **pp; 213 register int n; 214 char buf[BUFSIZ]; 215 int nserv = 0; /*%< number of nameserver records read from file */ 216 int haveenv = 0; 217 int havesearch = 0; 218 #ifdef RESOLVSORT 219 int nsort = 0; 220 char *net; 221 #endif 222 int dots; 223 union res_sockaddr_union u[2]; 224 int maxns = MAXNS; 225 226 RES_SET_H_ERRNO(statp, 0); 227 228 if ((statp->options & RES_INIT) != 0U) 229 res_ndestroy(statp); 230 231 if (!preinit) { 232 statp->retrans = RES_TIMEOUT; 233 statp->retry = RES_DFLRETRY; 234 statp->options = RES_DEFAULT; 235 } 236 statp->_rnd = malloc(16); 237 res_rndinit(statp); 238 statp->id = res_nrandomid(statp); 239 240 memset(u, 0, sizeof(u)); 241 #ifdef USELOOPBACK 242 u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1); 243 #else 244 u[nserv].sin.sin_addr.s_addr = INADDR_ANY; 245 #endif 246 u[nserv].sin.sin_family = AF_INET; 247 u[nserv].sin.sin_port = htons(NAMESERVER_PORT); 248 #ifdef HAVE_SA_LEN 249 u[nserv].sin.sin_len = sizeof(struct sockaddr_in); 250 #endif 251 nserv++; 252 #ifdef HAS_INET6_STRUCTS 253 #ifdef USELOOPBACK 254 u[nserv].sin6.sin6_addr = in6addr_loopback; 255 #else 256 u[nserv].sin6.sin6_addr = in6addr_any; 257 #endif 258 u[nserv].sin6.sin6_family = AF_INET6; 259 u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT); 260 #ifdef HAVE_SA_LEN 261 u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6); 262 #endif 263 nserv++; 264 #endif 265 statp->nscount = 0; 266 statp->ndots = 1; 267 statp->pfcode = 0; 268 statp->_vcsock = -1; 269 statp->_flags = 0; 270 statp->qhook = NULL; 271 statp->rhook = NULL; 272 statp->_u._ext.nscount = 0; 273 statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext)); 274 if (statp->_u._ext.ext != NULL) { 275 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext)); 276 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr; 277 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa"); 278 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int"); 279 } else { 280 /* 281 * Historically res_init() rarely, if at all, failed. 282 * Examples and applications exist which do not check 283 * our return code. Furthermore several applications 284 * simply call us to get the systems domainname. So 285 * rather than immediately fail here we store the 286 * failure, which is returned later, in h_errno. And 287 * prevent the collection of 'nameserver' information 288 * by setting maxns to 0. Thus applications that fail 289 * to check our return code wont be able to make 290 * queries anyhow. 291 */ 292 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 293 maxns = 0; 294 } 295 #ifdef RESOLVSORT 296 statp->nsort = 0; 297 #endif 298 res_setservers(statp, u, nserv); 299 300 #ifdef SOLARIS2 301 /* 302 * The old libresolv derived the defaultdomain from NIS/NIS+. 303 * We want to keep this behaviour 304 */ 305 { 306 char buf[sizeof(statp->defdname)], *cp; 307 int ret; 308 309 if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 && 310 (unsigned int)ret <= sizeof(buf)) { 311 if (buf[0] == '+') 312 buf[0] = '.'; 313 cp = strchr(buf, '.'); 314 cp = (cp == NULL) ? buf : (cp + 1); 315 (void)strlcpy(statp->defdname, cp, 316 sizeof(statp->defdname)); 317 } 318 } 319 #endif /* SOLARIS2 */ 320 321 /* Allow user to override the local domain definition */ 322 if ((cp = getenv("LOCALDOMAIN")) != NULL) { 323 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 324 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 325 haveenv++; 326 327 /* 328 * Set search list to be blank-separated strings 329 * from rest of env value. Permits users of LOCALDOMAIN 330 * to still have a search list, and anyone to set the 331 * one that they want to use as an individual (even more 332 * important now that the rfc1535 stuff restricts searches) 333 */ 334 cp = statp->defdname; 335 pp = statp->dnsrch; 336 *pp++ = cp; 337 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) { 338 if (*cp == '\n') /*%< silly backwards compat */ 339 break; 340 else if (*cp == ' ' || *cp == '\t') { 341 *cp = 0; 342 n = 1; 343 } else if (n) { 344 *pp++ = cp; 345 n = 0; 346 havesearch = 1; 347 } 348 } 349 /* null terminate last domain if there are excess */ 350 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n') 351 cp++; 352 *cp = '\0'; 353 *pp++ = 0; 354 } 355 356 #define MATCH(line, name) \ 357 (!strncmp(line, name, sizeof(name) - 1) && \ 358 (line[sizeof(name) - 1] == ' ' || \ 359 line[sizeof(name) - 1] == '\t')) 360 361 nserv = 0; 362 if ((fp = fopen(__res_conf_name, "re")) != NULL) { 363 struct stat st; 364 365 /* read the config file */ 366 while (fgets(buf, (int)sizeof(buf), fp) != NULL) { 367 /* skip comments */ 368 if (*buf == ';' || *buf == '#') 369 continue; 370 /* read default domain name */ 371 if (MATCH(buf, "domain")) { 372 if (haveenv) /*%< skip if have from environ */ 373 continue; 374 cp = buf + sizeof("domain") - 1; 375 while (*cp == ' ' || *cp == '\t') 376 cp++; 377 if ((*cp == '\0') || (*cp == '\n')) 378 continue; 379 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 380 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 381 if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL) 382 *cp = '\0'; 383 havesearch = 0; 384 continue; 385 } 386 /* set search list */ 387 if (MATCH(buf, "search")) { 388 if (haveenv) /*%< skip if have from environ */ 389 continue; 390 cp = buf + sizeof("search") - 1; 391 while (*cp == ' ' || *cp == '\t') 392 cp++; 393 if ((*cp == '\0') || (*cp == '\n')) 394 continue; 395 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); 396 statp->defdname[sizeof(statp->defdname) - 1] = '\0'; 397 if ((cp = strchr(statp->defdname, '\n')) != NULL) 398 *cp = '\0'; 399 /* 400 * Set search list to be blank-separated strings 401 * on rest of line. 402 */ 403 cp = statp->defdname; 404 pp = statp->dnsrch; 405 *pp++ = cp; 406 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) { 407 if (*cp == ' ' || *cp == '\t') { 408 *cp = 0; 409 n = 1; 410 } else if (n) { 411 *pp++ = cp; 412 n = 0; 413 } 414 } 415 /* null terminate last domain if there are excess */ 416 while (*cp != '\0' && *cp != ' ' && *cp != '\t') 417 cp++; 418 *cp = '\0'; 419 *pp++ = 0; 420 havesearch = 1; 421 continue; 422 } 423 /* read nameservers to query */ 424 if (MATCH(buf, "nameserver") && nserv < maxns) { 425 struct addrinfo hints, *ai; 426 char sbuf[NI_MAXSERV]; 427 const size_t minsiz = 428 sizeof(statp->_u._ext.ext->nsaddrs[0]); 429 430 cp = buf + sizeof("nameserver") - 1; 431 while (*cp == ' ' || *cp == '\t') 432 cp++; 433 cp[strcspn(cp, ";# \t\n")] = '\0'; 434 if ((*cp != '\0') && (*cp != '\n')) { 435 memset(&hints, 0, sizeof(hints)); 436 hints.ai_family = PF_UNSPEC; 437 hints.ai_socktype = SOCK_DGRAM; /*dummy*/ 438 hints.ai_flags = AI_NUMERICHOST; 439 sprintf(sbuf, "%u", NAMESERVER_PORT); 440 if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 && 441 ai->ai_addrlen <= minsiz) { 442 if (statp->_u._ext.ext != NULL) { 443 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 444 ai->ai_addr, ai->ai_addrlen); 445 } 446 if (ai->ai_addrlen <= 447 sizeof(statp->nsaddr_list[nserv])) { 448 memcpy(&statp->nsaddr_list[nserv], 449 ai->ai_addr, ai->ai_addrlen); 450 } else 451 statp->nsaddr_list[nserv].sin_family = 0; 452 freeaddrinfo(ai); 453 nserv++; 454 } 455 } 456 continue; 457 } 458 #ifdef RESOLVSORT 459 if (MATCH(buf, "sortlist")) { 460 struct in_addr a; 461 462 cp = buf + sizeof("sortlist") - 1; 463 while (nsort < MAXRESOLVSORT) { 464 while (*cp == ' ' || *cp == '\t') 465 cp++; 466 if (*cp == '\0' || *cp == '\n' || *cp == ';') 467 break; 468 net = cp; 469 while (*cp && !ISSORTMASK(*cp) && *cp != ';' && 470 isascii(*cp) && !isspace((unsigned char)*cp)) 471 cp++; 472 n = *cp; 473 *cp = 0; 474 if (inet_aton(net, &a)) { 475 statp->sort_list[nsort].addr = a; 476 if (ISSORTMASK(n)) { 477 *cp++ = n; 478 net = cp; 479 while (*cp && *cp != ';' && 480 isascii(*cp) && 481 !isspace((unsigned char)*cp)) 482 cp++; 483 n = *cp; 484 *cp = 0; 485 if (inet_aton(net, &a)) { 486 statp->sort_list[nsort].mask = a.s_addr; 487 } else { 488 statp->sort_list[nsort].mask = 489 net_mask(statp->sort_list[nsort].addr); 490 } 491 } else { 492 statp->sort_list[nsort].mask = 493 net_mask(statp->sort_list[nsort].addr); 494 } 495 nsort++; 496 } 497 *cp = n; 498 } 499 continue; 500 } 501 #endif 502 if (MATCH(buf, "options")) { 503 res_setoptions(statp, buf + sizeof("options") - 1, "conf"); 504 continue; 505 } 506 } 507 if (nserv > 0) 508 statp->nscount = nserv; 509 #ifdef RESOLVSORT 510 statp->nsort = nsort; 511 #endif 512 statp->_u._ext.ext->resfd = fcntl(fileno(fp), F_DUPFD_CLOEXEC, 0); 513 (void) fclose(fp); 514 if (fstat(statp->_u._ext.ext->resfd, &st) != -1) 515 __res_conf_time = statp->_u._ext.ext->res_conf_time = 516 st.st_mtimespec; 517 __res_kqinit(statp); 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 /* 575 * If the times are equal, then we check if there 576 * was a kevent related to resolv.conf and reload. 577 * If the times are not equal, then we don't bother 578 * to check the kevent, because another thread already 579 * did, loaded and changed the time. 580 */ 581 if (timespeccmp(&statp->_u._ext.ext->res_conf_time, 582 &__res_conf_time, ==)) { 583 struct kevent ke; 584 if (statp->_u._ext.ext->kq == -1) 585 goto out; 586 if (statp->_u._ext.ext->kqpid != getpid() && 587 __res_kqinit(statp) == -1) 588 goto out; 589 590 switch (kevent(statp->_u._ext.ext->kq, NULL, 0, &ke, 1, &ts)) { 591 case 0: 592 case -1: 593 out: 594 if (mtime) 595 *mtime = __res_conf_time; 596 return 0; 597 default: 598 break; 599 } 600 } 601 (void)__res_vinit(statp, 0); 602 if (mtime) 603 *mtime = __res_conf_time; 604 return 1; 605 } 606 607 static void 608 res_setoptions(res_state statp, const char *options, const char *source) 609 { 610 const char *cp = options; 611 int i; 612 size_t j; 613 struct __res_state_ext *ext = statp->_u._ext.ext; 614 615 #ifdef DEBUG 616 if (statp->options & RES_DEBUG) 617 printf(";; res_setoptions(\"%s\", \"%s\")...\n", 618 options, source); 619 #endif 620 while (*cp) { 621 /* skip leading and inner runs of spaces */ 622 while (*cp == ' ' || *cp == '\t') 623 cp++; 624 /* search for and process individual options */ 625 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) { 626 i = atoi(cp + sizeof("ndots:") - 1); 627 if (i <= RES_MAXNDOTS) 628 statp->ndots = i; 629 else 630 statp->ndots = RES_MAXNDOTS; 631 #ifdef DEBUG 632 if (statp->options & RES_DEBUG) 633 printf(";;\tndots=%d\n", statp->ndots); 634 #endif 635 } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) { 636 i = atoi(cp + sizeof("timeout:") - 1); 637 if (i <= RES_MAXRETRANS) 638 statp->retrans = i; 639 else 640 statp->retrans = RES_MAXRETRANS; 641 #ifdef DEBUG 642 if (statp->options & RES_DEBUG) 643 printf(";;\ttimeout=%d\n", statp->retrans); 644 #endif 645 #ifdef SOLARIS2 646 } else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) { 647 /* 648 * For backward compatibility, 'retrans' is 649 * supported as an alias for 'timeout', though 650 * without an imposed maximum. 651 */ 652 statp->retrans = atoi(cp + sizeof("retrans:") - 1); 653 } else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){ 654 /* 655 * For backward compatibility, 'retry' is 656 * supported as an alias for 'attempts', though 657 * without an imposed maximum. 658 */ 659 statp->retry = atoi(cp + sizeof("retry:") - 1); 660 #endif /* SOLARIS2 */ 661 } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){ 662 i = atoi(cp + sizeof("attempts:") - 1); 663 if (i <= RES_MAXRETRY) 664 statp->retry = i; 665 else 666 statp->retry = RES_MAXRETRY; 667 #ifdef DEBUG 668 if (statp->options & RES_DEBUG) 669 printf(";;\tattempts=%d\n", statp->retry); 670 #endif 671 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) { 672 #ifdef DEBUG 673 if (!(statp->options & RES_DEBUG)) { 674 printf(";; res_setoptions(\"%s\", \"%s\")..\n", 675 options, source); 676 statp->options |= RES_DEBUG; 677 } 678 printf(";;\tdebug\n"); 679 #endif 680 } else if (!strncmp(cp, "no_tld_query", 681 sizeof("no_tld_query") - 1) || 682 !strncmp(cp, "no-tld-query", 683 sizeof("no-tld-query") - 1)) { 684 statp->options |= RES_NOTLDQUERY; 685 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) { 686 statp->options |= RES_USE_INET6; 687 } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) { 688 statp->options |= RES_ROTATE; 689 } else if (!strncmp(cp, "no-check-names", 690 sizeof("no-check-names") - 1)) { 691 statp->options |= RES_NOCHECKNAME; 692 } else if (!strncmp(cp, "check-names", 693 sizeof("check-names") - 1)) { 694 statp->options &= ~RES_NOCHECKNAME; 695 } 696 #ifdef RES_USE_EDNS0 697 else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) { 698 statp->options |= RES_USE_EDNS0; 699 } 700 #endif 701 else if (!strncmp(cp, "dname", sizeof("dname") - 1)) { 702 statp->options |= RES_USE_DNAME; 703 } 704 else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) { 705 if (ext == NULL) 706 goto skip; 707 cp += sizeof("nibble:") - 1; 708 j = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1); 709 strncpy(ext->nsuffix, cp, j); 710 ext->nsuffix[j] = '\0'; 711 } 712 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) { 713 if (ext == NULL) 714 goto skip; 715 cp += sizeof("nibble2:") - 1; 716 j = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1); 717 strncpy(ext->nsuffix2, cp, j); 718 ext->nsuffix2[j] = '\0'; 719 } 720 else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) { 721 cp += sizeof("v6revmode:") - 1; 722 /* "nibble" and "bitstring" used to be valid */ 723 if (!strncmp(cp, "single", sizeof("single") - 1)) { 724 statp->options |= RES_NO_NIBBLE2; 725 } else if (!strncmp(cp, "both", sizeof("both") - 1)) { 726 statp->options &= 727 ~RES_NO_NIBBLE2; 728 } 729 } 730 else { 731 /* XXX - print a warning here? */ 732 } 733 skip: 734 /* skip to next run of spaces */ 735 while (*cp && *cp != ' ' && *cp != '\t') 736 cp++; 737 } 738 } 739 740 #ifdef RESOLVSORT 741 /* XXX - should really support CIDR which means explicit masks always. */ 742 static uint32_t 743 net_mask(struct in_addr in) /*!< XXX - should really use system's version of this */ 744 { 745 register uint32_t i = ntohl(in.s_addr); 746 747 if (IN_CLASSA(i)) 748 return (htonl(IN_CLASSA_NET)); 749 else if (IN_CLASSB(i)) 750 return (htonl(IN_CLASSB_NET)); 751 return (htonl(IN_CLASSC_NET)); 752 } 753 #endif 754 755 static u_char srnd[16]; 756 757 void 758 res_rndinit(res_state statp) 759 { 760 struct timeval now; 761 uint32_t u32; 762 uint16_t u16; 763 u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd; 764 765 gettimeofday(&now, NULL); 766 u32 = (uint32_t)now.tv_sec; 767 memcpy(rnd, &u32, 4); 768 u32 = now.tv_usec; 769 memcpy(rnd + 4, &u32, 4); 770 u32 += (uint32_t)now.tv_sec; 771 memcpy(rnd + 8, &u32, 4); 772 u16 = getpid(); 773 memcpy(rnd + 12, &u16, 2); 774 } 775 776 u_int 777 res_nrandomid(res_state statp) 778 { 779 struct timeval now; 780 uint16_t u16; 781 MD5_CTX ctx; 782 u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd; 783 784 gettimeofday(&now, NULL); 785 u16 = (uint16_t) (now.tv_sec ^ now.tv_usec); 786 memcpy(rnd + 14, &u16, 2); 787 #ifndef HAVE_MD5 788 MD5_Init(&ctx); 789 MD5_Update(&ctx, rnd, 16); 790 MD5_Final(rnd, &ctx); 791 #else 792 MD5Init(&ctx); 793 MD5Update(&ctx, rnd, 16); 794 MD5Final(rnd, &ctx); 795 #endif 796 memcpy(&u16, rnd + 14, 2); 797 return ((u_int) u16); 798 } 799 800 /*% 801 * This routine is for closing the socket if a virtual circuit is used and 802 * the program wants to close it. This provides support for endhostent() 803 * which expects to close the socket. 804 * 805 * This routine is not expected to be user visible. 806 */ 807 void 808 res_nclose(res_state statp) 809 { 810 int ns; 811 812 if (statp->_vcsock >= 0) { 813 (void) close(statp->_vcsock); 814 statp->_vcsock = -1; 815 statp->_flags &= ~(RES_F_VC | RES_F_CONN); 816 } 817 for (ns = 0; ns < statp->_u._ext.nscount; ns++) { 818 if (statp->_u._ext.nssocks[ns] != -1) { 819 (void) close(statp->_u._ext.nssocks[ns]); 820 statp->_u._ext.nssocks[ns] = -1; 821 } 822 } 823 } 824 825 void 826 res_ndestroy(res_state statp) 827 { 828 struct __res_state_ext *ext = statp->_u._ext.ext; 829 res_nclose(statp); 830 if (ext != NULL) { 831 if (ext->kq != -1 && ext->kqpid == getpid()) 832 (void)close(ext->kq); 833 if (ext->resfd != -1) 834 (void)close(ext->resfd); 835 free(ext); 836 statp->_u._ext.ext = NULL; 837 } 838 if (statp->_rnd != NULL) { 839 free(statp->_rnd); 840 statp->_rnd = NULL; 841 } 842 statp->options &= ~RES_INIT; 843 } 844 845 const char * 846 res_get_nibblesuffix(res_state statp) 847 { 848 if (statp->_u._ext.ext) 849 return (statp->_u._ext.ext->nsuffix); 850 return ("ip6.arpa"); 851 } 852 853 const char * 854 res_get_nibblesuffix2(res_state statp) 855 { 856 if (statp->_u._ext.ext) 857 return (statp->_u._ext.ext->nsuffix2); 858 return ("ip6.int"); 859 } 860 861 void 862 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) 863 { 864 int i, nserv; 865 size_t size; 866 867 /* close open servers */ 868 res_nclose(statp); 869 870 /* cause rtt times to be forgotten */ 871 statp->_u._ext.nscount = 0; 872 873 nserv = 0; 874 for (i = 0; i < cnt && nserv < MAXNS; i++) { 875 switch (set->sin.sin_family) { 876 case AF_INET: 877 size = sizeof(set->sin); 878 if (statp->_u._ext.ext) 879 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 880 &set->sin, size); 881 if (size <= sizeof(statp->nsaddr_list[nserv])) 882 memcpy(&statp->nsaddr_list[nserv], 883 &set->sin, size); 884 else 885 statp->nsaddr_list[nserv].sin_family = 0; 886 nserv++; 887 break; 888 889 #ifdef HAS_INET6_STRUCTS 890 case AF_INET6: 891 size = sizeof(set->sin6); 892 if (statp->_u._ext.ext) 893 memcpy(&statp->_u._ext.ext->nsaddrs[nserv], 894 &set->sin6, size); 895 if (size <= sizeof(statp->nsaddr_list[nserv])) 896 memcpy(&statp->nsaddr_list[nserv], 897 &set->sin6, size); 898 else 899 statp->nsaddr_list[nserv].sin_family = 0; 900 nserv++; 901 break; 902 #endif 903 904 default: 905 break; 906 } 907 set++; 908 } 909 statp->nscount = nserv; 910 911 } 912 913 int 914 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) 915 { 916 int i; 917 size_t size; 918 uint16_t family; 919 920 for (i = 0; i < statp->nscount && i < cnt; i++) { 921 if (statp->_u._ext.ext) 922 family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family; 923 else 924 family = statp->nsaddr_list[i].sin_family; 925 926 switch (family) { 927 case AF_INET: 928 size = sizeof(set->sin); 929 if (statp->_u._ext.ext) 930 memcpy(&set->sin, 931 &statp->_u._ext.ext->nsaddrs[i], 932 size); 933 else 934 memcpy(&set->sin, &statp->nsaddr_list[i], 935 size); 936 break; 937 938 #ifdef HAS_INET6_STRUCTS 939 case AF_INET6: 940 size = sizeof(set->sin6); 941 if (statp->_u._ext.ext) 942 memcpy(&set->sin6, 943 &statp->_u._ext.ext->nsaddrs[i], 944 size); 945 else 946 memcpy(&set->sin6, &statp->nsaddr_list[i], 947 size); 948 break; 949 #endif 950 951 default: 952 set->sin.sin_family = 0; 953 break; 954 } 955 set++; 956 } 957 return (statp->nscount); 958 } 959 960 /*! \file */ 961
Indexes created Mon Sep 22 13:09:51 GMT 2025