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. 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 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 32 * 33 * Permission to use, copy, modify, and distribute this software for any 34 * purpose with or without fee is hereby granted, provided that the above 35 * copyright notice and this permission notice appear in all copies, and that 36 * the name of Digital Equipment Corporation not be used in advertising or 37 * publicity pertaining to distribution of the document or software without 38 * specific, written prior permission. 39 * 40 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 41 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 42 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 43 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 44 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 45 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 46 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 47 * SOFTWARE. 48 * - 49 * --Copyright-- 50 * 51 * @(#)gethostnamadr.c 8.1 (Berkeley) 6/4/93 52 * $From: Id: gethnamaddr.c,v 8.23 1998/04/07 04:59:46 vixie Exp $ 53 * $FreeBSD: src/lib/libc/net/gethostbydns.c,v 1.27.2.5 2002/11/02 18:54:57 ume Exp $ 54 * $DragonFly: src/lib/libc/net/gethostbydns.c,v 1.6 2005/11/13 02:04:47 swildner Exp $ 55 */ 56 57 #include <sys/types.h> 58 #include <sys/param.h> 59 #include <sys/socket.h> 60 #include <netinet/in.h> 61 #include <arpa/inet.h> 62 #include <arpa/nameser.h> 63 64 #include <stdio.h> 65 #include <stdlib.h> 66 #include <unistd.h> 67 #include <string.h> 68 #include <netdb.h> 69 #include <resolv.h> 70 #include <ctype.h> 71 #include <errno.h> 72 #include <syslog.h> 73 74 #include "res_config.h" 75 76 #define SPRINTF(x) ((size_t)sprintf x) 77 78 #define MAXALIASES 35 79 #define MAXADDRS 35 80 81 static const char AskedForGot[] = 82 "gethostby*.gethostanswer: asked for \"%s\", got \"%s\""; 83 84 static char *h_addr_ptrs[MAXADDRS + 1]; 85 86 static struct hostent host; 87 static char *host_aliases[MAXALIASES]; 88 static char hostbuf[8*1024]; 89 static u_char host_addr[16]; /* IPv4 or IPv6 */ 90 91 #ifdef RESOLVSORT 92 static void addrsort (char **, int); 93 #endif 94 95 #define MAXPACKET (64*1024) 96 97 typedef union { 98 HEADER hdr; 99 u_char buf[MAXPACKET]; 100 } querybuf; 101 102 typedef union { 103 int32_t al; 104 char ac; 105 } align; 106 107 extern int h_errno; 108 int _dns_ttl_; 109 110 #ifdef DEBUG 111 static void 112 dprintf(char *msg, int num) 113 { 114 if (_res.options & RES_DEBUG) { 115 int save = errno; 116 117 printf(msg, num); 118 errno = save; 119 } 120 } 121 #else 122 # define dprintf(msg, num) /*nada*/ 123 #endif 124 125 #define BOUNDED_INCR(x) \ 126 do { \ 127 cp += x; \ 128 if (cp > eom) { \ 129 h_errno = NO_RECOVERY; \ 130 return (NULL); \ 131 } \ 132 } while (0) 133 134 #define BOUNDS_CHECK(ptr, count) \ 135 do { \ 136 if ((ptr) + (count) > eom) { \ 137 h_errno = NO_RECOVERY; \ 138 return (NULL); \ 139 } \ 140 } while (0) 141 142 static struct hostent * 143 gethostanswer(const querybuf *answer, int anslen, const char *qname, int qtype) 144 { 145 const HEADER *hp; 146 const u_char *cp; 147 int n; 148 const u_char *eom, *erdata; 149 char *bp, **ap, **hap; 150 int type, class, buflen, ancount, qdcount; 151 int haveanswer, had_error; 152 int toobig = 0; 153 char tbuf[MAXDNAME]; 154 const char *tname; 155 int (*name_ok) (const char *); 156 157 tname = qname; 158 host.h_name = NULL; 159 eom = answer->buf + anslen; 160 switch (qtype) { 161 case T_A: 162 case T_AAAA: 163 name_ok = res_hnok; 164 break; 165 case T_PTR: 166 name_ok = res_dnok; 167 break; 168 default: 169 h_errno = NO_RECOVERY; 170 return (NULL); /* XXX should be abort(); */ 171 } 172 /* 173 * find first satisfactory answer 174 */ 175 hp = &answer->hdr; 176 ancount = ntohs(hp->ancount); 177 qdcount = ntohs(hp->qdcount); 178 bp = hostbuf; 179 buflen = sizeof hostbuf; 180 cp = answer->buf; 181 BOUNDED_INCR(HFIXEDSZ); 182 if (qdcount != 1) { 183 h_errno = NO_RECOVERY; 184 return (NULL); 185 } 186 n = dn_expand(answer->buf, eom, cp, bp, buflen); 187 if ((n < 0) || !(*name_ok)(bp)) { 188 h_errno = NO_RECOVERY; 189 return (NULL); 190 } 191 BOUNDED_INCR(n + QFIXEDSZ); 192 if (qtype == T_A || qtype == T_AAAA) { 193 /* res_send() has already verified that the query name is the 194 * same as the one we sent; this just gets the expanded name 195 * (i.e., with the succeeding search-domain tacked on). 196 */ 197 n = strlen(bp) + 1; /* for the \0 */ 198 if (n >= MAXHOSTNAMELEN) { 199 h_errno = NO_RECOVERY; 200 return (NULL); 201 } 202 host.h_name = bp; 203 bp += n; 204 buflen -= n; 205 /* The qname can be abbreviated, but h_name is now absolute. */ 206 qname = host.h_name; 207 } 208 ap = host_aliases; 209 *ap = NULL; 210 host.h_aliases = host_aliases; 211 hap = h_addr_ptrs; 212 *hap = NULL; 213 host.h_addr_list = h_addr_ptrs; 214 haveanswer = 0; 215 had_error = 0; 216 _dns_ttl_ = -1; 217 while (ancount-- > 0 && cp < eom && !had_error) { 218 n = dn_expand(answer->buf, eom, cp, bp, buflen); 219 if ((n < 0) || !(*name_ok)(bp)) { 220 had_error++; 221 continue; 222 } 223 cp += n; /* name */ 224 BOUNDS_CHECK(cp, 3 * INT16SZ + INT32SZ); 225 type = _getshort(cp); 226 cp += INT16SZ; /* type */ 227 class = _getshort(cp); 228 cp += INT16SZ; /* class */ 229 if (qtype == T_A && type == T_A) 230 _dns_ttl_ = _getlong(cp); 231 cp += INT32SZ; /* TTL */ 232 n = _getshort(cp); 233 cp += INT16SZ; /* len */ 234 BOUNDS_CHECK(cp, n); 235 erdata = cp + n; 236 if (class != C_IN) { 237 /* XXX - debug? syslog? */ 238 cp += n; 239 continue; /* XXX - had_error++ ? */ 240 } 241 if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME) { 242 if (ap >= &host_aliases[MAXALIASES-1]) 243 continue; 244 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 245 if ((n < 0) || !(*name_ok)(tbuf)) { 246 had_error++; 247 continue; 248 } 249 cp += n; 250 if (cp != erdata) { 251 h_errno = NO_RECOVERY; 252 return (NULL); 253 } 254 /* Store alias. */ 255 *ap++ = bp; 256 n = strlen(bp) + 1; /* for the \0 */ 257 if (n >= MAXHOSTNAMELEN) { 258 had_error++; 259 continue; 260 } 261 bp += n; 262 buflen -= n; 263 /* Get canonical name. */ 264 n = strlen(tbuf) + 1; /* for the \0 */ 265 if (n > buflen || n >= MAXHOSTNAMELEN) { 266 had_error++; 267 continue; 268 } 269 strcpy(bp, tbuf); 270 host.h_name = bp; 271 bp += n; 272 buflen -= n; 273 continue; 274 } 275 if (qtype == T_PTR && type == T_CNAME) { 276 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 277 if (n < 0 || !res_dnok(tbuf)) { 278 had_error++; 279 continue; 280 } 281 cp += n; 282 if (cp != erdata) { 283 h_errno = NO_RECOVERY; 284 return (NULL); 285 } 286 /* Get canonical name. */ 287 n = strlen(tbuf) + 1; /* for the \0 */ 288 if (n > buflen || n >= MAXHOSTNAMELEN) { 289 had_error++; 290 continue; 291 } 292 strcpy(bp, tbuf); 293 tname = bp; 294 bp += n; 295 buflen -= n; 296 continue; 297 } 298 if (type != qtype) { 299 if (type != T_SIG) 300 syslog(LOG_NOTICE|LOG_AUTH, 301 "gethostby*.gethostanswer: asked for \"%s %s %s\", got type \"%s\"", 302 qname, p_class(C_IN), p_type(qtype), 303 p_type(type)); 304 cp += n; 305 continue; /* XXX - had_error++ ? */ 306 } 307 switch (type) { 308 case T_PTR: 309 if (strcasecmp(tname, bp) != 0) { 310 syslog(LOG_NOTICE|LOG_AUTH, 311 AskedForGot, qname, bp); 312 cp += n; 313 continue; /* XXX - had_error++ ? */ 314 } 315 n = dn_expand(answer->buf, eom, cp, bp, buflen); 316 if ((n < 0) || !res_hnok(bp)) { 317 had_error++; 318 break; 319 } 320 #if MULTI_PTRS_ARE_ALIASES 321 cp += n; 322 if (cp != erdata) { 323 h_errno = NO_RECOVERY; 324 return (NULL); 325 } 326 if (!haveanswer) 327 host.h_name = bp; 328 else if (ap < &host_aliases[MAXALIASES-1]) 329 *ap++ = bp; 330 else 331 n = -1; 332 if (n != -1) { 333 n = strlen(bp) + 1; /* for the \0 */ 334 if (n >= MAXHOSTNAMELEN) { 335 had_error++; 336 break; 337 } 338 bp += n; 339 buflen -= n; 340 } 341 break; 342 #else 343 host.h_name = bp; 344 if (_res.options & RES_USE_INET6) { 345 n = strlen(bp) + 1; /* for the \0 */ 346 if (n >= MAXHOSTNAMELEN) { 347 had_error++; 348 break; 349 } 350 bp += n; 351 buflen -= n; 352 _map_v4v6_hostent(&host, &bp, &buflen); 353 } 354 h_errno = NETDB_SUCCESS; 355 return (&host); 356 #endif 357 case T_A: 358 case T_AAAA: 359 if (strcasecmp(host.h_name, bp) != 0) { 360 syslog(LOG_NOTICE|LOG_AUTH, 361 AskedForGot, host.h_name, bp); 362 cp += n; 363 continue; /* XXX - had_error++ ? */ 364 } 365 if (n != host.h_length) { 366 cp += n; 367 continue; 368 } 369 if (!haveanswer) { 370 int nn; 371 372 host.h_name = bp; 373 nn = strlen(bp) + 1; /* for the \0 */ 374 bp += nn; 375 buflen -= nn; 376 } 377 378 buflen -= sizeof(align) - ((u_long)bp % sizeof(align)); 379 bp += sizeof(align) - ((u_long)bp % sizeof(align)); 380 381 if (bp + n >= &hostbuf[sizeof hostbuf]) { 382 dprintf("size (%d) too big\n", n); 383 had_error++; 384 continue; 385 } 386 if (hap >= &h_addr_ptrs[MAXADDRS-1]) { 387 if (!toobig++) 388 dprintf("Too many addresses (%d)\n", 389 MAXADDRS); 390 cp += n; 391 continue; 392 } 393 bcopy(cp, *hap++ = bp, n); 394 bp += n; 395 buflen -= n; 396 cp += n; 397 if (cp != erdata) { 398 h_errno = NO_RECOVERY; 399 return (NULL); 400 } 401 break; 402 default: 403 dprintf("Impossible condition (type=%d)\n", type); 404 h_errno = NO_RECOVERY; 405 return (NULL); 406 /* BIND has abort() here, too risky on bad data */ 407 } 408 if (!had_error) 409 haveanswer++; 410 } 411 if (haveanswer) { 412 *ap = NULL; 413 *hap = NULL; 414 # if defined(RESOLVSORT) 415 /* 416 * Note: we sort even if host can take only one address 417 * in its return structures - should give it the "best" 418 * address in that case, not some random one 419 */ 420 if (_res.nsort && haveanswer > 1 && qtype == T_A) 421 addrsort(h_addr_ptrs, haveanswer); 422 # endif /*RESOLVSORT*/ 423 if (!host.h_name) { 424 n = strlen(qname) + 1; /* for the \0 */ 425 if (n > buflen || n >= MAXHOSTNAMELEN) 426 goto no_recovery; 427 strcpy(bp, qname); 428 host.h_name = bp; 429 bp += n; 430 buflen -= n; 431 } 432 if (_res.options & RES_USE_INET6) 433 _map_v4v6_hostent(&host, &bp, &buflen); 434 h_errno = NETDB_SUCCESS; 435 return (&host); 436 } 437 no_recovery: 438 h_errno = NO_RECOVERY; 439 return (NULL); 440 } 441 442 struct hostent * 443 __dns_getanswer(const char *answer, int anslen, const char *qname, int qtype) 444 { 445 switch(qtype) { 446 case T_AAAA: 447 host.h_addrtype = AF_INET6; 448 host.h_length = IN6ADDRSZ; 449 break; 450 case T_A: 451 default: 452 host.h_addrtype = AF_INET; 453 host.h_length = INADDRSZ; 454 break; 455 } 456 457 return(gethostanswer((const querybuf *)answer, anslen, qname, qtype)); 458 } 459 460 struct hostent * 461 _gethostbydnsname(const char *name, int af) 462 { 463 querybuf *buf; 464 const char *cp; 465 char *bp; 466 int n, size, type, len; 467 struct hostent *hp; 468 469 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 470 h_errno = NETDB_INTERNAL; 471 return (NULL); 472 } 473 474 switch (af) { 475 case AF_INET: 476 size = INADDRSZ; 477 type = T_A; 478 break; 479 case AF_INET6: 480 size = IN6ADDRSZ; 481 type = T_AAAA; 482 break; 483 default: 484 h_errno = NETDB_INTERNAL; 485 errno = EAFNOSUPPORT; 486 return (NULL); 487 } 488 489 host.h_addrtype = af; 490 host.h_length = size; 491 492 /* 493 * if there aren't any dots, it could be a user-level alias. 494 * this is also done in res_query() since we are not the only 495 * function that looks up host names. 496 */ 497 if (!strchr(name, '.') && (cp = __hostalias(name))) 498 name = cp; 499 500 /* 501 * disallow names consisting only of digits/dots, unless 502 * they end in a dot. 503 */ 504 if (isdigit((unsigned char)name[0])) 505 for (cp = name;; ++cp) { 506 if (!*cp) { 507 if (*--cp == '.') 508 break; 509 /* 510 * All-numeric, no dot at the end. 511 * Fake up a hostent as if we'd actually 512 * done a lookup. 513 */ 514 if (inet_pton(af, name, host_addr) <= 0) { 515 h_errno = HOST_NOT_FOUND; 516 return (NULL); 517 } 518 strncpy(hostbuf, name, MAXDNAME); 519 hostbuf[MAXDNAME] = '\0'; 520 bp = hostbuf + MAXDNAME; 521 len = sizeof hostbuf - MAXDNAME; 522 host.h_name = hostbuf; 523 host.h_aliases = host_aliases; 524 host_aliases[0] = NULL; 525 h_addr_ptrs[0] = (char *)host_addr; 526 h_addr_ptrs[1] = NULL; 527 host.h_addr_list = h_addr_ptrs; 528 if (_res.options & RES_USE_INET6) 529 _map_v4v6_hostent(&host, &bp, &len); 530 h_errno = NETDB_SUCCESS; 531 return (&host); 532 } 533 if (!isdigit((unsigned char)*cp) && *cp != '.') 534 break; 535 } 536 if ((isxdigit((unsigned char)name[0]) && strchr(name, ':') != NULL) || 537 name[0] == ':') 538 for (cp = name;; ++cp) { 539 if (!*cp) { 540 if (*--cp == '.') 541 break; 542 /* 543 * All-IPv6-legal, no dot at the end. 544 * Fake up a hostent as if we'd actually 545 * done a lookup. 546 */ 547 if (inet_pton(af, name, host_addr) <= 0) { 548 h_errno = HOST_NOT_FOUND; 549 return (NULL); 550 } 551 strncpy(hostbuf, name, MAXDNAME); 552 hostbuf[MAXDNAME] = '\0'; 553 bp = hostbuf + MAXDNAME; 554 len = sizeof hostbuf - MAXDNAME; 555 host.h_name = hostbuf; 556 host.h_aliases = host_aliases; 557 host_aliases[0] = NULL; 558 h_addr_ptrs[0] = (char *)host_addr; 559 h_addr_ptrs[1] = NULL; 560 host.h_addr_list = h_addr_ptrs; 561 h_errno = NETDB_SUCCESS; 562 return (&host); 563 } 564 if (!isxdigit((unsigned char)*cp) && *cp != ':' && *cp != '.') 565 break; 566 } 567 568 if ((buf = malloc(sizeof(*buf))) == NULL) { 569 h_errno = NETDB_INTERNAL; 570 return (NULL); 571 } 572 n = res_search(name, C_IN, type, buf->buf, sizeof(buf->buf)); 573 if (n < 0) { 574 free(buf); 575 dprintf("res_search failed (%d)\n", n); 576 return (NULL); 577 } else if (n > sizeof(buf->buf)) { 578 free(buf); 579 dprintf("static buffer is too small (%d)\n", n); 580 return (NULL); 581 } 582 hp = gethostanswer(buf, n, name, type); 583 free(buf); 584 return (hp); 585 } 586 587 struct hostent * 588 _gethostbydnsaddr(const char *addr, /* XXX should have been def'd as u_char! */ 589 int len, 590 int af) 591 { 592 const u_char *uaddr = (const u_char *)addr; 593 static const u_char mapped[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0xff,0xff }; 594 static const u_char tunnelled[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0,0 }; 595 int n, size; 596 querybuf *buf; 597 struct hostent *hp; 598 char qbuf[MAXDNAME+1], *qp; 599 #ifdef SUNSECURITY 600 struct hostent *rhp; 601 char **haddr; 602 u_long old_options; 603 char hname2[MAXDNAME+1]; 604 #endif /*SUNSECURITY*/ 605 606 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 607 h_errno = NETDB_INTERNAL; 608 return (NULL); 609 } 610 if (af == AF_INET6 && len == IN6ADDRSZ && 611 (!bcmp(uaddr, mapped, sizeof mapped) || 612 !bcmp(uaddr, tunnelled, sizeof tunnelled))) { 613 /* Unmap. */ 614 addr += sizeof mapped; 615 uaddr += sizeof mapped; 616 af = AF_INET; 617 len = INADDRSZ; 618 } 619 switch (af) { 620 case AF_INET: 621 size = INADDRSZ; 622 break; 623 case AF_INET6: 624 size = IN6ADDRSZ; 625 break; 626 default: 627 errno = EAFNOSUPPORT; 628 h_errno = NETDB_INTERNAL; 629 return (NULL); 630 } 631 if (size != len) { 632 errno = EINVAL; 633 h_errno = NETDB_INTERNAL; 634 return (NULL); 635 } 636 switch (af) { 637 case AF_INET: 638 sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa", 639 (uaddr[3] & 0xff), 640 (uaddr[2] & 0xff), 641 (uaddr[1] & 0xff), 642 (uaddr[0] & 0xff)); 643 break; 644 case AF_INET6: 645 qp = qbuf; 646 for (n = IN6ADDRSZ - 1; n >= 0; n--) { 647 qp += SPRINTF((qp, "%x.%x.", 648 uaddr[n] & 0xf, 649 (uaddr[n] >> 4) & 0xf)); 650 } 651 strlcat(qbuf, "ip6.arpa", sizeof(qbuf)); 652 break; 653 default: 654 abort(); 655 } 656 if ((buf = malloc(sizeof(*buf))) == NULL) { 657 h_errno = NETDB_INTERNAL; 658 return (NULL); 659 } 660 n = res_query(qbuf, C_IN, T_PTR, (u_char *)buf->buf, sizeof buf->buf); 661 if (n < 0 && af == AF_INET6) { 662 *qp = '\0'; 663 strlcat(qbuf, "ip6.int", sizeof(qbuf)); 664 n = res_query(qbuf, C_IN, T_PTR, (u_char *)buf->buf, 665 sizeof buf->buf); 666 } 667 if (n < 0) { 668 free(buf); 669 dprintf("res_query failed (%d)\n", n); 670 return (NULL); 671 } 672 if (n > sizeof buf->buf) { 673 free(buf); 674 dprintf("static buffer is too small (%d)\n", n); 675 return (NULL); 676 } 677 if (!(hp = gethostanswer(buf, n, qbuf, T_PTR))) { 678 free(buf); 679 return (NULL); /* h_errno was set by gethostanswer() */ 680 } 681 free(buf); 682 #ifdef SUNSECURITY 683 if (af == AF_INET) { 684 /* 685 * turn off search as the name should be absolute, 686 * 'localhost' should be matched by defnames 687 */ 688 strncpy(hname2, hp->h_name, MAXDNAME); 689 hname2[MAXDNAME] = '\0'; 690 old_options = _res.options; 691 _res.options &= ~RES_DNSRCH; 692 _res.options |= RES_DEFNAMES; 693 if (!(rhp = gethostbyname(hname2))) { 694 syslog(LOG_NOTICE|LOG_AUTH, 695 "gethostbyaddr: No A record for %s (verifying [%s])", 696 hname2, inet_ntoa(*((struct in_addr *)addr))); 697 _res.options = old_options; 698 h_errno = HOST_NOT_FOUND; 699 return (NULL); 700 } 701 _res.options = old_options; 702 for (haddr = rhp->h_addr_list; *haddr; haddr++) 703 if (!memcmp(*haddr, addr, INADDRSZ)) 704 break; 705 if (!*haddr) { 706 syslog(LOG_NOTICE|LOG_AUTH, 707 "gethostbyaddr: A record of %s != PTR record [%s]", 708 hname2, inet_ntoa(*((struct in_addr *)addr))); 709 h_errno = HOST_NOT_FOUND; 710 return (NULL); 711 } 712 } 713 #endif /*SUNSECURITY*/ 714 hp->h_addrtype = af; 715 hp->h_length = len; 716 bcopy(addr, host_addr, len); 717 h_addr_ptrs[0] = (char *)host_addr; 718 h_addr_ptrs[1] = NULL; 719 if (af == AF_INET && (_res.options & RES_USE_INET6)) { 720 _map_v4v6_address((char*)host_addr, (char*)host_addr); 721 hp->h_addrtype = AF_INET6; 722 hp->h_length = IN6ADDRSZ; 723 } 724 h_errno = NETDB_SUCCESS; 725 return (hp); 726 } 727 728 #ifdef RESOLVSORT 729 static void 730 addrsort(char **ap, int num) 731 { 732 int i, j; 733 char **p; 734 short aval[MAXADDRS]; 735 int needsort = 0; 736 737 p = ap; 738 for (i = 0; i < num; i++, p++) { 739 for (j = 0 ; (unsigned)j < _res.nsort; j++) 740 if (_res.sort_list[j].addr.s_addr == 741 (((struct in_addr *)(*p))->s_addr & _res.sort_list[j].mask)) 742 break; 743 aval[i] = j; 744 if (needsort == 0 && i > 0 && j < aval[i-1]) 745 needsort = i; 746 } 747 if (!needsort) 748 return; 749 750 while (needsort < num) { 751 for (j = needsort - 1; j >= 0; j--) { 752 if (aval[j] > aval[j+1]) { 753 char *hp; 754 755 i = aval[j]; 756 aval[j] = aval[j+1]; 757 aval[j+1] = i; 758 759 hp = ap[j]; 760 ap[j] = ap[j+1]; 761 ap[j+1] = hp; 762 763 } else 764 break; 765 } 766 needsort++; 767 } 768 } 769 #endif 770 void 771 _sethostdnsent(int stayopen) 772 { 773 if ((_res.options & RES_INIT) == 0 && res_init() == -1) 774 return; 775 if (stayopen) 776 _res.options |= RES_STAYOPEN | RES_USEVC; 777 } 778 779 void 780 _endhostdnsent(void) 781 { 782 _res.options &= ~(RES_STAYOPEN | RES_USEVC); 783 res_close(); 784 } 785