1 /* 2 * ++Copyright++ 1985, 1988, 1993 3 * - 4 * Copyright (c) 1985, 1988, 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 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 36 * 37 * Permission to use, copy, modify, and distribute this software for any 38 * purpose with or without fee is hereby granted, provided that the above 39 * copyright notice and this permission notice appear in all copies, and that 40 * the name of Digital Equipment Corporation not be used in advertising or 41 * publicity pertaining to distribution of the document or software without 42 * specific, written prior permission. 43 * 44 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 45 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 46 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 47 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 48 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 49 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 50 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 51 * SOFTWARE. 52 * - 53 * --Copyright-- 54 * 55 * @(#)gethostnamadr.c 8.1 (Berkeley) 6/4/93 56 * $From: Id: gethnamaddr.c,v 8.23 1998/04/07 04:59:46 vixie Exp $ 57 * $FreeBSD: src/lib/libc/net/gethostbydns.c,v 1.27.2.5 2002/11/02 18:54:57 ume Exp $ 58 * $DragonFly: src/lib/libc/net/gethostbydns.c,v 1.3 2003/11/12 20:21:24 eirikn Exp $ 59 */ 60 61 #include <sys/types.h> 62 #include <sys/param.h> 63 #include <sys/socket.h> 64 #include <netinet/in.h> 65 #include <arpa/inet.h> 66 #include <arpa/nameser.h> 67 68 #include <stdio.h> 69 #include <stdlib.h> 70 #include <unistd.h> 71 #include <string.h> 72 #include <netdb.h> 73 #include <resolv.h> 74 #include <ctype.h> 75 #include <errno.h> 76 #include <syslog.h> 77 78 #include "res_config.h" 79 80 #define SPRINTF(x) ((size_t)sprintf x) 81 82 #define MAXALIASES 35 83 #define MAXADDRS 35 84 85 static const char AskedForGot[] = 86 "gethostby*.gethostanswer: asked for \"%s\", got \"%s\""; 87 88 static char *h_addr_ptrs[MAXADDRS + 1]; 89 90 static struct hostent host; 91 static char *host_aliases[MAXALIASES]; 92 static char hostbuf[8*1024]; 93 static u_char host_addr[16]; /* IPv4 or IPv6 */ 94 95 #ifdef RESOLVSORT 96 static void addrsort (char **, int); 97 #endif 98 99 #define MAXPACKET (64*1024) 100 101 typedef union { 102 HEADER hdr; 103 u_char buf[MAXPACKET]; 104 } querybuf; 105 106 typedef union { 107 int32_t al; 108 char ac; 109 } align; 110 111 extern int h_errno; 112 int _dns_ttl_; 113 114 #ifdef DEBUG 115 static void 116 dprintf(msg, num) 117 char *msg; 118 int num; 119 { 120 if (_res.options & RES_DEBUG) { 121 int save = errno; 122 123 printf(msg, num); 124 errno = save; 125 } 126 } 127 #else 128 # define dprintf(msg, num) /*nada*/ 129 #endif 130 131 #define BOUNDED_INCR(x) \ 132 do { \ 133 cp += x; \ 134 if (cp > eom) { \ 135 h_errno = NO_RECOVERY; \ 136 return (NULL); \ 137 } \ 138 } while (0) 139 140 #define BOUNDS_CHECK(ptr, count) \ 141 do { \ 142 if ((ptr) + (count) > eom) { \ 143 h_errno = NO_RECOVERY; \ 144 return (NULL); \ 145 } \ 146 } while (0) 147 148 static struct hostent * 149 gethostanswer(answer, anslen, qname, qtype) 150 const querybuf *answer; 151 int anslen; 152 const char *qname; 153 int qtype; 154 { 155 register const HEADER *hp; 156 register const u_char *cp; 157 register int n; 158 const u_char *eom, *erdata; 159 char *bp, **ap, **hap; 160 int type, class, buflen, ancount, qdcount; 161 int haveanswer, had_error; 162 int toobig = 0; 163 char tbuf[MAXDNAME]; 164 const char *tname; 165 int (*name_ok) (const char *); 166 167 tname = qname; 168 host.h_name = NULL; 169 eom = answer->buf + anslen; 170 switch (qtype) { 171 case T_A: 172 case T_AAAA: 173 name_ok = res_hnok; 174 break; 175 case T_PTR: 176 name_ok = res_dnok; 177 break; 178 default: 179 h_errno = NO_RECOVERY; 180 return (NULL); /* XXX should be abort(); */ 181 } 182 /* 183 * find first satisfactory answer 184 */ 185 hp = &answer->hdr; 186 ancount = ntohs(hp->ancount); 187 qdcount = ntohs(hp->qdcount); 188 bp = hostbuf; 189 buflen = sizeof hostbuf; 190 cp = answer->buf; 191 BOUNDED_INCR(HFIXEDSZ); 192 if (qdcount != 1) { 193 h_errno = NO_RECOVERY; 194 return (NULL); 195 } 196 n = dn_expand(answer->buf, eom, cp, bp, buflen); 197 if ((n < 0) || !(*name_ok)(bp)) { 198 h_errno = NO_RECOVERY; 199 return (NULL); 200 } 201 BOUNDED_INCR(n + QFIXEDSZ); 202 if (qtype == T_A || qtype == T_AAAA) { 203 /* res_send() has already verified that the query name is the 204 * same as the one we sent; this just gets the expanded name 205 * (i.e., with the succeeding search-domain tacked on). 206 */ 207 n = strlen(bp) + 1; /* for the \0 */ 208 if (n >= MAXHOSTNAMELEN) { 209 h_errno = NO_RECOVERY; 210 return (NULL); 211 } 212 host.h_name = bp; 213 bp += n; 214 buflen -= n; 215 /* The qname can be abbreviated, but h_name is now absolute. */ 216 qname = host.h_name; 217 } 218 ap = host_aliases; 219 *ap = NULL; 220 host.h_aliases = host_aliases; 221 hap = h_addr_ptrs; 222 *hap = NULL; 223 host.h_addr_list = h_addr_ptrs; 224 haveanswer = 0; 225 had_error = 0; 226 _dns_ttl_ = -1; 227 while (ancount-- > 0 && cp < eom && !had_error) { 228 n = dn_expand(answer->buf, eom, cp, bp, buflen); 229 if ((n < 0) || !(*name_ok)(bp)) { 230 had_error++; 231 continue; 232 } 233 cp += n; /* name */ 234 BOUNDS_CHECK(cp, 3 * INT16SZ + INT32SZ); 235 type = _getshort(cp); 236 cp += INT16SZ; /* type */ 237 class = _getshort(cp); 238 cp += INT16SZ; /* class */ 239 if (qtype == T_A && type == T_A) 240 _dns_ttl_ = _getlong(cp); 241 cp += INT32SZ; /* TTL */ 242 n = _getshort(cp); 243 cp += INT16SZ; /* len */ 244 BOUNDS_CHECK(cp, n); 245 erdata = cp + n; 246 if (class != C_IN) { 247 /* XXX - debug? syslog? */ 248 cp += n; 249 continue; /* XXX - had_error++ ? */ 250 } 251 if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME) { 252 if (ap >= &host_aliases[MAXALIASES-1]) 253 continue; 254 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 255 if ((n < 0) || !(*name_ok)(tbuf)) { 256 had_error++; 257 continue; 258 } 259 cp += n; 260 if (cp != erdata) { 261 h_errno = NO_RECOVERY; 262 return (NULL); 263 } 264 /* Store alias. */ 265 *ap++ = bp; 266 n = strlen(bp) + 1; /* for the \0 */ 267 if (n >= MAXHOSTNAMELEN) { 268 had_error++; 269 continue; 270 } 271 bp += n; 272 buflen -= n; 273 /* Get canonical name. */ 274 n = strlen(tbuf) + 1; /* for the \0 */ 275 if (n > buflen || n >= MAXHOSTNAMELEN) { 276 had_error++; 277 continue; 278 } 279 strcpy(bp, tbuf); 280 host.h_name = bp; 281 bp += n; 282 buflen -= n; 283 continue; 284 } 285 if (qtype == T_PTR && type == T_CNAME) { 286 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 287 if (n < 0 || !res_dnok(tbuf)) { 288 had_error++; 289 continue; 290 } 291 cp += n; 292 if (cp != erdata) { 293 h_errno = NO_RECOVERY; 294 return (NULL); 295 } 296 /* Get canonical name. */ 297 n = strlen(tbuf) + 1; /* for the \0 */ 298 if (n > buflen || n >= MAXHOSTNAMELEN) { 299 had_error++; 300 continue; 301 } 302 strcpy(bp, tbuf); 303 tname = bp; 304 bp += n; 305 buflen -= n; 306 continue; 307 } 308 if (type != qtype) { 309 if (type != T_SIG) 310 syslog(LOG_NOTICE|LOG_AUTH, 311 "gethostby*.gethostanswer: asked for \"%s %s %s\", got type \"%s\"", 312 qname, p_class(C_IN), p_type(qtype), 313 p_type(type)); 314 cp += n; 315 continue; /* XXX - had_error++ ? */ 316 } 317 switch (type) { 318 case T_PTR: 319 if (strcasecmp(tname, bp) != 0) { 320 syslog(LOG_NOTICE|LOG_AUTH, 321 AskedForGot, qname, bp); 322 cp += n; 323 continue; /* XXX - had_error++ ? */ 324 } 325 n = dn_expand(answer->buf, eom, cp, bp, buflen); 326 if ((n < 0) || !res_hnok(bp)) { 327 had_error++; 328 break; 329 } 330 #if MULTI_PTRS_ARE_ALIASES 331 cp += n; 332 if (cp != erdata) { 333 h_errno = NO_RECOVERY; 334 return (NULL); 335 } 336 if (!haveanswer) 337 host.h_name = bp; 338 else if (ap < &host_aliases[MAXALIASES-1]) 339 *ap++ = bp; 340 else 341 n = -1; 342 if (n != -1) { 343 n = strlen(bp) + 1; /* for the \0 */ 344 if (n >= MAXHOSTNAMELEN) { 345 had_error++; 346 break; 347 } 348 bp += n; 349 buflen -= n; 350 } 351 break; 352 #else 353 host.h_name = bp; 354 if (_res.options & RES_USE_INET6) { 355 n = strlen(bp) + 1; /* for the \0 */ 356 if (n >= MAXHOSTNAMELEN) { 357 had_error++; 358 break; 359 } 360 bp += n; 361 buflen -= n; 362 _map_v4v6_hostent(&host, &bp, &buflen); 363 } 364 h_errno = NETDB_SUCCESS; 365 return (&host); 366 #endif 367 case T_A: 368 case T_AAAA: 369 if (strcasecmp(host.h_name, bp) != 0) { 370 syslog(LOG_NOTICE|LOG_AUTH, 371 AskedForGot, host.h_name, bp); 372 cp += n; 373 continue; /* XXX - had_error++ ? */ 374 } 375 if (n != host.h_length) { 376 cp += n; 377 continue; 378 } 379 if (!haveanswer) { 380 register int nn; 381 382 host.h_name = bp; 383 nn = strlen(bp) + 1; /* for the \0 */ 384 bp += nn; 385 buflen -= nn; 386 } 387 388 buflen -= sizeof(align) - ((u_long)bp % sizeof(align)); 389 bp += sizeof(align) - ((u_long)bp % sizeof(align)); 390 391 if (bp + n >= &hostbuf[sizeof hostbuf]) { 392 dprintf("size (%d) too big\n", n); 393 had_error++; 394 continue; 395 } 396 if (hap >= &h_addr_ptrs[MAXADDRS-1]) { 397 if (!toobig++) 398 dprintf("Too many addresses (%d)\n", 399 MAXADDRS); 400 cp += n; 401 continue; 402 } 403 bcopy(cp, *hap++ = bp, n); 404 bp += n; 405 buflen -= n; 406 cp += n; 407 if (cp != erdata) { 408 h_errno = NO_RECOVERY; 409 return (NULL); 410 } 411 break; 412 default: 413 dprintf("Impossible condition (type=%d)\n", type); 414 h_errno = NO_RECOVERY; 415 return (NULL); 416 /* BIND has abort() here, too risky on bad data */ 417 } 418 if (!had_error) 419 haveanswer++; 420 } 421 if (haveanswer) { 422 *ap = NULL; 423 *hap = NULL; 424 # if defined(RESOLVSORT) 425 /* 426 * Note: we sort even if host can take only one address 427 * in its return structures - should give it the "best" 428 * address in that case, not some random one 429 */ 430 if (_res.nsort && haveanswer > 1 && qtype == T_A) 431 addrsort(h_addr_ptrs, haveanswer); 432 # endif /*RESOLVSORT*/ 433 if (!host.h_name) { 434 n = strlen(qname) + 1; /* for the \0 */ 435 if (n > buflen || n >= MAXHOSTNAMELEN) 436 goto no_recovery; 437 strcpy(bp, qname); 438 host.h_name = bp; 439 bp += n; 440 buflen -= n; 441 } 442 if (_res.options & RES_USE_INET6) 443 _map_v4v6_hostent(&host, &bp, &buflen); 444 h_errno = NETDB_SUCCESS; 445 return (&host); 446 } 447 no_recovery: 448 h_errno = NO_RECOVERY; 449 return (NULL); 450 } 451 452 struct hostent * 453 __dns_getanswer(answer, anslen, qname, qtype) 454 const char *answer; 455 int anslen; 456 const char *qname; 457 int qtype; 458 { 459 switch(qtype) { 460 case T_AAAA: 461 host.h_addrtype = AF_INET6; 462 host.h_length = IN6ADDRSZ; 463 break; 464 case T_A: 465 default: 466 host.h_addrtype = AF_INET; 467 host.h_length = INADDRSZ; 468 break; 469 } 470 471 return(gethostanswer((const querybuf *)answer, anslen, qname, qtype)); 472 } 473 474 struct hostent * 475 _gethostbydnsname(name, af) 476 const char *name; 477 int af; 478 { 479 querybuf *buf; 480 register const char *cp; 481 char *bp; 482 int n, size, type, len; 483 struct hostent *hp; 484 485 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 486 h_errno = NETDB_INTERNAL; 487 return (NULL); 488 } 489 490 switch (af) { 491 case AF_INET: 492 size = INADDRSZ; 493 type = T_A; 494 break; 495 case AF_INET6: 496 size = IN6ADDRSZ; 497 type = T_AAAA; 498 break; 499 default: 500 h_errno = NETDB_INTERNAL; 501 errno = EAFNOSUPPORT; 502 return (NULL); 503 } 504 505 host.h_addrtype = af; 506 host.h_length = size; 507 508 /* 509 * if there aren't any dots, it could be a user-level alias. 510 * this is also done in res_query() since we are not the only 511 * function that looks up host names. 512 */ 513 if (!strchr(name, '.') && (cp = __hostalias(name))) 514 name = cp; 515 516 /* 517 * disallow names consisting only of digits/dots, unless 518 * they end in a dot. 519 */ 520 if (isdigit((unsigned char)name[0])) 521 for (cp = name;; ++cp) { 522 if (!*cp) { 523 if (*--cp == '.') 524 break; 525 /* 526 * All-numeric, no dot at the end. 527 * Fake up a hostent as if we'd actually 528 * done a lookup. 529 */ 530 if (inet_pton(af, name, host_addr) <= 0) { 531 h_errno = HOST_NOT_FOUND; 532 return (NULL); 533 } 534 strncpy(hostbuf, name, MAXDNAME); 535 hostbuf[MAXDNAME] = '\0'; 536 bp = hostbuf + MAXDNAME; 537 len = sizeof hostbuf - MAXDNAME; 538 host.h_name = hostbuf; 539 host.h_aliases = host_aliases; 540 host_aliases[0] = NULL; 541 h_addr_ptrs[0] = (char *)host_addr; 542 h_addr_ptrs[1] = NULL; 543 host.h_addr_list = h_addr_ptrs; 544 if (_res.options & RES_USE_INET6) 545 _map_v4v6_hostent(&host, &bp, &len); 546 h_errno = NETDB_SUCCESS; 547 return (&host); 548 } 549 if (!isdigit((unsigned char)*cp) && *cp != '.') 550 break; 551 } 552 if ((isxdigit((unsigned char)name[0]) && strchr(name, ':') != NULL) || 553 name[0] == ':') 554 for (cp = name;; ++cp) { 555 if (!*cp) { 556 if (*--cp == '.') 557 break; 558 /* 559 * All-IPv6-legal, no dot at the end. 560 * Fake up a hostent as if we'd actually 561 * done a lookup. 562 */ 563 if (inet_pton(af, name, host_addr) <= 0) { 564 h_errno = HOST_NOT_FOUND; 565 return (NULL); 566 } 567 strncpy(hostbuf, name, MAXDNAME); 568 hostbuf[MAXDNAME] = '\0'; 569 bp = hostbuf + MAXDNAME; 570 len = sizeof hostbuf - MAXDNAME; 571 host.h_name = hostbuf; 572 host.h_aliases = host_aliases; 573 host_aliases[0] = NULL; 574 h_addr_ptrs[0] = (char *)host_addr; 575 h_addr_ptrs[1] = NULL; 576 host.h_addr_list = h_addr_ptrs; 577 h_errno = NETDB_SUCCESS; 578 return (&host); 579 } 580 if (!isxdigit((unsigned char)*cp) && *cp != ':' && *cp != '.') 581 break; 582 } 583 584 if ((buf = malloc(sizeof(*buf))) == NULL) { 585 h_errno = NETDB_INTERNAL; 586 return (NULL); 587 } 588 n = res_search(name, C_IN, type, buf->buf, sizeof(buf->buf)); 589 if (n < 0) { 590 free(buf); 591 dprintf("res_search failed (%d)\n", n); 592 return (NULL); 593 } else if (n > sizeof(buf->buf)) { 594 free(buf); 595 dprintf("static buffer is too small (%d)\n", n); 596 return (NULL); 597 } 598 hp = gethostanswer(buf, n, name, type); 599 free(buf); 600 return (hp); 601 } 602 603 struct hostent * 604 _gethostbydnsaddr(addr, len, af) 605 const char *addr; /* XXX should have been def'd as u_char! */ 606 int len, af; 607 { 608 const u_char *uaddr = (const u_char *)addr; 609 static const u_char mapped[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0xff,0xff }; 610 static const u_char tunnelled[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0,0 }; 611 int n, size; 612 querybuf *buf; 613 register struct hostent *hp; 614 char qbuf[MAXDNAME+1], *qp; 615 #ifdef SUNSECURITY 616 register struct hostent *rhp; 617 char **haddr; 618 u_long old_options; 619 char hname2[MAXDNAME+1]; 620 #endif /*SUNSECURITY*/ 621 622 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 623 h_errno = NETDB_INTERNAL; 624 return (NULL); 625 } 626 if (af == AF_INET6 && len == IN6ADDRSZ && 627 (!bcmp(uaddr, mapped, sizeof mapped) || 628 !bcmp(uaddr, tunnelled, sizeof tunnelled))) { 629 /* Unmap. */ 630 addr += sizeof mapped; 631 uaddr += sizeof mapped; 632 af = AF_INET; 633 len = INADDRSZ; 634 } 635 switch (af) { 636 case AF_INET: 637 size = INADDRSZ; 638 break; 639 case AF_INET6: 640 size = IN6ADDRSZ; 641 break; 642 default: 643 errno = EAFNOSUPPORT; 644 h_errno = NETDB_INTERNAL; 645 return (NULL); 646 } 647 if (size != len) { 648 errno = EINVAL; 649 h_errno = NETDB_INTERNAL; 650 return (NULL); 651 } 652 switch (af) { 653 case AF_INET: 654 (void) sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa", 655 (uaddr[3] & 0xff), 656 (uaddr[2] & 0xff), 657 (uaddr[1] & 0xff), 658 (uaddr[0] & 0xff)); 659 break; 660 case AF_INET6: 661 qp = qbuf; 662 for (n = IN6ADDRSZ - 1; n >= 0; n--) { 663 qp += SPRINTF((qp, "%x.%x.", 664 uaddr[n] & 0xf, 665 (uaddr[n] >> 4) & 0xf)); 666 } 667 strlcat(qbuf, "ip6.arpa", sizeof(qbuf)); 668 break; 669 default: 670 abort(); 671 } 672 if ((buf = malloc(sizeof(*buf))) == NULL) { 673 h_errno = NETDB_INTERNAL; 674 return (NULL); 675 } 676 n = res_query(qbuf, C_IN, T_PTR, (u_char *)buf->buf, sizeof buf->buf); 677 if (n < 0 && af == AF_INET6) { 678 *qp = '\0'; 679 strlcat(qbuf, "ip6.int", sizeof(qbuf)); 680 n = res_query(qbuf, C_IN, T_PTR, (u_char *)buf->buf, 681 sizeof buf->buf); 682 } 683 if (n < 0) { 684 free(buf); 685 dprintf("res_query failed (%d)\n", n); 686 return (NULL); 687 } 688 if (n > sizeof buf->buf) { 689 free(buf); 690 dprintf("static buffer is too small (%d)\n", n); 691 return (NULL); 692 } 693 if (!(hp = gethostanswer(buf, n, qbuf, T_PTR))) { 694 free(buf); 695 return (NULL); /* h_errno was set by gethostanswer() */ 696 } 697 free(buf); 698 #ifdef SUNSECURITY 699 if (af == AF_INET) { 700 /* 701 * turn off search as the name should be absolute, 702 * 'localhost' should be matched by defnames 703 */ 704 strncpy(hname2, hp->h_name, MAXDNAME); 705 hname2[MAXDNAME] = '\0'; 706 old_options = _res.options; 707 _res.options &= ~RES_DNSRCH; 708 _res.options |= RES_DEFNAMES; 709 if (!(rhp = gethostbyname(hname2))) { 710 syslog(LOG_NOTICE|LOG_AUTH, 711 "gethostbyaddr: No A record for %s (verifying [%s])", 712 hname2, inet_ntoa(*((struct in_addr *)addr))); 713 _res.options = old_options; 714 h_errno = HOST_NOT_FOUND; 715 return (NULL); 716 } 717 _res.options = old_options; 718 for (haddr = rhp->h_addr_list; *haddr; haddr++) 719 if (!memcmp(*haddr, addr, INADDRSZ)) 720 break; 721 if (!*haddr) { 722 syslog(LOG_NOTICE|LOG_AUTH, 723 "gethostbyaddr: A record of %s != PTR record [%s]", 724 hname2, inet_ntoa(*((struct in_addr *)addr))); 725 h_errno = HOST_NOT_FOUND; 726 return (NULL); 727 } 728 } 729 #endif /*SUNSECURITY*/ 730 hp->h_addrtype = af; 731 hp->h_length = len; 732 bcopy(addr, host_addr, len); 733 h_addr_ptrs[0] = (char *)host_addr; 734 h_addr_ptrs[1] = NULL; 735 if (af == AF_INET && (_res.options & RES_USE_INET6)) { 736 _map_v4v6_address((char*)host_addr, (char*)host_addr); 737 hp->h_addrtype = AF_INET6; 738 hp->h_length = IN6ADDRSZ; 739 } 740 h_errno = NETDB_SUCCESS; 741 return (hp); 742 } 743 744 #ifdef RESOLVSORT 745 static void 746 addrsort(ap, num) 747 char **ap; 748 int num; 749 { 750 int i, j; 751 char **p; 752 short aval[MAXADDRS]; 753 int needsort = 0; 754 755 p = ap; 756 for (i = 0; i < num; i++, p++) { 757 for (j = 0 ; (unsigned)j < _res.nsort; j++) 758 if (_res.sort_list[j].addr.s_addr == 759 (((struct in_addr *)(*p))->s_addr & _res.sort_list[j].mask)) 760 break; 761 aval[i] = j; 762 if (needsort == 0 && i > 0 && j < aval[i-1]) 763 needsort = i; 764 } 765 if (!needsort) 766 return; 767 768 while (needsort < num) { 769 for (j = needsort - 1; j >= 0; j--) { 770 if (aval[j] > aval[j+1]) { 771 char *hp; 772 773 i = aval[j]; 774 aval[j] = aval[j+1]; 775 aval[j+1] = i; 776 777 hp = ap[j]; 778 ap[j] = ap[j+1]; 779 ap[j+1] = hp; 780 781 } else 782 break; 783 } 784 needsort++; 785 } 786 } 787 #endif 788 void 789 _sethostdnsent(stayopen) 790 int stayopen; 791 { 792 if ((_res.options & RES_INIT) == 0 && res_init() == -1) 793 return; 794 if (stayopen) 795 _res.options |= RES_STAYOPEN | RES_USEVC; 796 } 797 798 void 799 _endhostdnsent() 800 { 801 _res.options &= ~(RES_STAYOPEN | RES_USEVC); 802 res_close(); 803 } 804