gethnamaddr.c revision 1.42.2.5
1 /* $NetBSD: gethnamaddr.c,v 1.42.2.5 2002/07/29 15:23:35 lukem Exp $ */ 2 3 /* 4 * ++Copyright++ 1985, 1988, 1993 5 * - 6 * Copyright (c) 1985, 1988, 1993 7 * The Regents of the University of California. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the University of 20 * California, Berkeley and its contributors. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 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 * --Copyright-- 56 */ 57 58 #include <sys/cdefs.h> 59 #if defined(LIBC_SCCS) && !defined(lint) 60 #if 0 61 static char sccsid[] = "@(#)gethostnamadr.c 8.1 (Berkeley) 6/4/93"; 62 static char rcsid[] = "Id: gethnamaddr.c,v 8.21 1997/06/01 20:34:37 vixie Exp "; 63 #else 64 __RCSID("$NetBSD: gethnamaddr.c,v 1.42.2.5 2002/07/29 15:23:35 lukem Exp $"); 65 #endif 66 #endif /* LIBC_SCCS and not lint */ 67 68 #if defined(_LIBC) 69 #include "namespace.h" 70 #endif 71 #include <sys/param.h> 72 #include <sys/socket.h> 73 #include <netinet/in.h> 74 #include <arpa/inet.h> 75 #include <arpa/nameser.h> 76 77 #include <assert.h> 78 #include <ctype.h> 79 #include <errno.h> 80 #include <netdb.h> 81 #include <resolv.h> 82 #include <stdio.h> 83 #include <syslog.h> 84 85 #ifdef __STDC__ 86 #include <stdarg.h> 87 #else 88 #include <varargs.h> 89 #endif 90 91 #ifndef LOG_AUTH 92 # define LOG_AUTH 0 93 #endif 94 95 #define MULTI_PTRS_ARE_ALIASES 1 /* XXX - experimental */ 96 97 #include <nsswitch.h> 98 #include <stdlib.h> 99 #include <string.h> 100 101 #ifdef YP 102 #include <rpc/rpc.h> 103 #include <rpcsvc/yp_prot.h> 104 #include <rpcsvc/ypclnt.h> 105 #endif 106 107 #if defined(_LIBC) && defined(__weak_alias) 108 __weak_alias(gethostbyaddr,_gethostbyaddr) 109 __weak_alias(gethostbyname,_gethostbyname) 110 #endif 111 112 #define MAXALIASES 35 113 #define MAXADDRS 35 114 115 static const char AskedForGot[] = 116 "gethostby*.getanswer: asked for \"%s\", got \"%s\""; 117 118 static char *h_addr_ptrs[MAXADDRS + 1]; 119 120 #ifdef YP 121 static char *__ypdomain; 122 #endif 123 124 static struct hostent host; 125 static char *host_aliases[MAXALIASES]; 126 static char hostbuf[8*1024]; 127 static u_int32_t host_addr[16 / sizeof(u_int32_t)]; /* IPv4 or IPv6 */ 128 static FILE *hostf = NULL; 129 static int stayopen = 0; 130 131 132 #if PACKETSZ > 1024 133 #define MAXPACKET PACKETSZ 134 #else 135 #define MAXPACKET 1024 136 #endif 137 138 typedef union { 139 HEADER hdr; 140 u_char buf[MAXPACKET]; 141 } querybuf; 142 143 typedef union { 144 int32_t al; 145 char ac; 146 } align; 147 148 #ifdef DEBUG 149 static void dprintf __P((char *, ...)) 150 __attribute__((__format__(__printf__, 1, 2))); 151 #endif 152 static struct hostent *getanswer __P((const querybuf *, int, 153 const char *, int)); 154 static void map_v4v6_address __P((const char *, char *)); 155 static void map_v4v6_hostent __P((struct hostent *, char **, char *)); 156 #ifdef RESOLVSORT 157 static void addrsort __P((char **, int)); 158 #endif 159 160 void _sethtent __P((int)); 161 void _endhtent __P((void)); 162 struct hostent *_gethtent __P((void)); 163 struct hostent *_gethtbyname2 __P((const char *, int)); 164 void ht_sethostent __P((int)); 165 void ht_endhostent __P((void)); 166 struct hostent *ht_gethostbyname __P((char *)); 167 struct hostent *ht_gethostbyaddr __P((const char *, int, int )); 168 void dns_service __P((void)); 169 #undef dn_skipname 170 int dn_skipname __P((const u_char *, const u_char *)); 171 int _gethtbyaddr __P((void *, void *, va_list)); 172 int _gethtbyname __P((void *, void *, va_list)); 173 int _dns_gethtbyaddr __P((void *, void *, va_list)); 174 int _dns_gethtbyname __P((void *, void *, va_list)); 175 #ifdef YP 176 struct hostent *_yphostent __P((char *, int)); 177 int _yp_gethtbyaddr __P((void *, void *, va_list)); 178 int _yp_gethtbyname __P((void *, void *, va_list)); 179 #endif 180 181 static const ns_src default_dns_files[] = { 182 { NSSRC_FILES, NS_SUCCESS }, 183 { NSSRC_DNS, NS_SUCCESS }, 184 { 0 } 185 }; 186 187 188 #ifdef DEBUG 189 static void 190 dprintf(char *msg, ...) 191 { 192 _DIAGASSERT(msg != NULL); 193 194 if (_res.options & RES_DEBUG) { 195 int save = errno; 196 va_list ap; 197 198 va_start (ap, msg); 199 vprintf(msg, ap); 200 va_end (ap); 201 202 errno = save; 203 } 204 } 205 #else 206 # define dprintf(msg, num) /*nada*/ 207 #endif 208 209 #define BOUNDED_INCR(x) \ 210 do { \ 211 cp += x; \ 212 if (cp > eom) { \ 213 h_errno = NO_RECOVERY; \ 214 return (NULL); \ 215 } \ 216 } while (/*CONSTCOND*/0) 217 218 #define BOUNDS_CHECK(ptr, count) \ 219 do { \ 220 if ((ptr) + (count) > eom) { \ 221 h_errno = NO_RECOVERY; \ 222 return (NULL); \ 223 } \ 224 } while (/*CONSTCOND*/0) 225 226 static struct hostent * 227 getanswer(answer, anslen, qname, qtype) 228 const querybuf *answer; 229 int anslen; 230 const char *qname; 231 int qtype; 232 { 233 const HEADER *hp; 234 const u_char *cp; 235 int n; 236 const u_char *eom, *erdata; 237 char *bp, **ap, **hap, *ep; 238 int type, class, ancount, qdcount; 239 int haveanswer, had_error; 240 int toobig = 0; 241 char tbuf[MAXDNAME]; 242 const char *tname; 243 int (*name_ok) __P((const char *)); 244 245 _DIAGASSERT(answer != NULL); 246 _DIAGASSERT(qname != NULL); 247 248 tname = qname; 249 host.h_name = NULL; 250 eom = answer->buf + anslen; 251 switch (qtype) { 252 case T_A: 253 case T_AAAA: 254 name_ok = res_hnok; 255 break; 256 case T_PTR: 257 name_ok = res_dnok; 258 break; 259 default: 260 return (NULL); /* XXX should be abort(); */ 261 } 262 /* 263 * find first satisfactory answer 264 */ 265 hp = &answer->hdr; 266 ancount = ntohs(hp->ancount); 267 qdcount = ntohs(hp->qdcount); 268 bp = hostbuf; 269 ep = hostbuf + sizeof hostbuf; 270 cp = answer->buf; 271 BOUNDED_INCR(HFIXEDSZ); 272 if (qdcount != 1) { 273 h_errno = NO_RECOVERY; 274 return (NULL); 275 } 276 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 277 if ((n < 0) || !(*name_ok)(bp)) { 278 h_errno = NO_RECOVERY; 279 return (NULL); 280 } 281 BOUNDED_INCR(n + QFIXEDSZ); 282 if (qtype == T_A || qtype == T_AAAA) { 283 /* res_send() has already verified that the query name is the 284 * same as the one we sent; this just gets the expanded name 285 * (i.e., with the succeeding search-domain tacked on). 286 */ 287 n = strlen(bp) + 1; /* for the \0 */ 288 if (n >= MAXHOSTNAMELEN) { 289 h_errno = NO_RECOVERY; 290 return (NULL); 291 } 292 host.h_name = bp; 293 bp += n; 294 /* The qname can be abbreviated, but h_name is now absolute. */ 295 qname = host.h_name; 296 } 297 ap = host_aliases; 298 *ap = NULL; 299 host.h_aliases = host_aliases; 300 hap = h_addr_ptrs; 301 *hap = NULL; 302 host.h_addr_list = h_addr_ptrs; 303 haveanswer = 0; 304 had_error = 0; 305 while (ancount-- > 0 && cp < eom && !had_error) { 306 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 307 if ((n < 0) || !(*name_ok)(bp)) { 308 had_error++; 309 continue; 310 } 311 cp += n; /* name */ 312 BOUNDS_CHECK(cp, 3 * INT16SZ + INT32SZ); 313 type = _getshort(cp); 314 cp += INT16SZ; /* type */ 315 class = _getshort(cp); 316 cp += INT16SZ + INT32SZ; /* class, TTL */ 317 n = _getshort(cp); 318 cp += INT16SZ; /* len */ 319 BOUNDS_CHECK(cp, n); 320 erdata = cp + n; 321 if (class != C_IN) { 322 /* XXX - debug? syslog? */ 323 cp += n; 324 continue; /* XXX - had_error++ ? */ 325 } 326 if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME) { 327 if (ap >= &host_aliases[MAXALIASES-1]) 328 continue; 329 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 330 if ((n < 0) || !(*name_ok)(tbuf)) { 331 had_error++; 332 continue; 333 } 334 cp += n; 335 if (cp != erdata) { 336 h_errno = NO_RECOVERY; 337 return (NULL); 338 } 339 /* Store alias. */ 340 *ap++ = bp; 341 n = strlen(bp) + 1; /* for the \0 */ 342 if (n >= MAXHOSTNAMELEN) { 343 had_error++; 344 continue; 345 } 346 bp += n; 347 /* Get canonical name. */ 348 n = strlen(tbuf) + 1; /* for the \0 */ 349 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 350 had_error++; 351 continue; 352 } 353 strcpy(bp, tbuf); 354 host.h_name = bp; 355 bp += n; 356 continue; 357 } 358 if (qtype == T_PTR && type == T_CNAME) { 359 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 360 if (n < 0 || !res_dnok(tbuf)) { 361 had_error++; 362 continue; 363 } 364 cp += n; 365 if (cp != erdata) { 366 h_errno = NO_RECOVERY; 367 return (NULL); 368 } 369 /* Get canonical name. */ 370 n = strlen(tbuf) + 1; /* for the \0 */ 371 if (n > ep - bp || n >= MAXHOSTNAMELEN) { 372 had_error++; 373 continue; 374 } 375 strcpy(bp, tbuf); 376 tname = bp; 377 bp += n; 378 continue; 379 } 380 if (type != qtype) { 381 if (type != T_KEY && type != T_SIG) 382 syslog(LOG_NOTICE|LOG_AUTH, 383 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", 384 qname, p_class(C_IN), p_type(qtype), 385 p_type(type)); 386 cp += n; 387 continue; /* XXX - had_error++ ? */ 388 } 389 switch (type) { 390 case T_PTR: 391 if (strcasecmp(tname, bp) != 0) { 392 syslog(LOG_NOTICE|LOG_AUTH, 393 AskedForGot, qname, bp); 394 cp += n; 395 continue; /* XXX - had_error++ ? */ 396 } 397 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 398 if ((n < 0) || !res_hnok(bp)) { 399 had_error++; 400 break; 401 } 402 #if MULTI_PTRS_ARE_ALIASES 403 cp += n; 404 if (cp != erdata) { 405 h_errno = NO_RECOVERY; 406 return (NULL); 407 } 408 if (!haveanswer) 409 host.h_name = bp; 410 else if (ap < &host_aliases[MAXALIASES-1]) 411 *ap++ = bp; 412 else 413 n = -1; 414 if (n != -1) { 415 n = strlen(bp) + 1; /* for the \0 */ 416 if (n >= MAXHOSTNAMELEN) { 417 had_error++; 418 break; 419 } 420 bp += n; 421 } 422 break; 423 #else 424 host.h_name = bp; 425 if (_res.options & RES_USE_INET6) { 426 n = strlen(bp) + 1; /* for the \0 */ 427 if (n >= MAXHOSTNAMELEN) { 428 had_error++; 429 break; 430 } 431 bp += n; 432 map_v4v6_hostent(&host, &bp, ep); 433 } 434 h_errno = NETDB_SUCCESS; 435 return (&host); 436 #endif 437 case T_A: 438 case T_AAAA: 439 if (strcasecmp(host.h_name, bp) != 0) { 440 syslog(LOG_NOTICE|LOG_AUTH, 441 AskedForGot, host.h_name, bp); 442 cp += n; 443 continue; /* XXX - had_error++ ? */ 444 } 445 if (n != host.h_length) { 446 cp += n; 447 continue; 448 } 449 if (!haveanswer) { 450 int nn; 451 452 host.h_name = bp; 453 nn = strlen(bp) + 1; /* for the \0 */ 454 bp += nn; 455 } 456 457 bp += sizeof(align) - 458 (size_t)((u_long)bp % sizeof(align)); 459 460 if (bp + n >= &hostbuf[sizeof hostbuf]) { 461 dprintf("size (%d) too big\n", n); 462 had_error++; 463 continue; 464 } 465 if (hap >= &h_addr_ptrs[MAXADDRS-1]) { 466 if (!toobig++) 467 dprintf("Too many addresses (%d)\n", 468 MAXADDRS); 469 cp += n; 470 continue; 471 } 472 (void)memcpy(*hap++ = bp, cp, (size_t)n); 473 bp += n; 474 cp += n; 475 if (cp != erdata) { 476 h_errno = NO_RECOVERY; 477 return (NULL); 478 } 479 break; 480 default: 481 abort(); 482 } 483 if (!had_error) 484 haveanswer++; 485 } 486 if (haveanswer) { 487 *ap = NULL; 488 *hap = NULL; 489 # if defined(RESOLVSORT) 490 /* 491 * Note: we sort even if host can take only one address 492 * in its return structures - should give it the "best" 493 * address in that case, not some random one 494 */ 495 if (_res.nsort && haveanswer > 1 && qtype == T_A) 496 addrsort(h_addr_ptrs, haveanswer); 497 # endif /*RESOLVSORT*/ 498 if (!host.h_name) { 499 n = strlen(qname) + 1; /* for the \0 */ 500 if (n > ep - bp || n >= MAXHOSTNAMELEN) 501 goto no_recovery; 502 strcpy(bp, qname); 503 host.h_name = bp; 504 bp += n; 505 } 506 if (_res.options & RES_USE_INET6) 507 map_v4v6_hostent(&host, &bp, ep); 508 h_errno = NETDB_SUCCESS; 509 return (&host); 510 } 511 no_recovery: 512 h_errno = NO_RECOVERY; 513 return (NULL); 514 } 515 516 struct hostent * 517 gethostbyname(name) 518 const char *name; 519 { 520 struct hostent *hp; 521 522 _DIAGASSERT(name != NULL); 523 524 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 525 h_errno = NETDB_INTERNAL; 526 return (NULL); 527 } 528 if (_res.options & RES_USE_INET6) { 529 hp = gethostbyname2(name, AF_INET6); 530 if (hp) 531 return (hp); 532 } 533 return (gethostbyname2(name, AF_INET)); 534 } 535 536 struct hostent * 537 gethostbyname2(name, af) 538 const char *name; 539 int af; 540 { 541 const char *cp; 542 char *bp, *ep; 543 int size; 544 struct hostent *hp; 545 static const ns_dtab dtab[] = { 546 NS_FILES_CB(_gethtbyname, NULL) 547 { NSSRC_DNS, _dns_gethtbyname, NULL }, /* force -DHESIOD */ 548 NS_NIS_CB(_yp_gethtbyname, NULL) 549 { 0 } 550 }; 551 552 _DIAGASSERT(name != NULL); 553 554 switch (af) { 555 case AF_INET: 556 size = INADDRSZ; 557 break; 558 case AF_INET6: 559 size = IN6ADDRSZ; 560 break; 561 default: 562 h_errno = NETDB_INTERNAL; 563 errno = EAFNOSUPPORT; 564 return (NULL); 565 } 566 567 host.h_addrtype = af; 568 host.h_length = size; 569 570 /* 571 * if there aren't any dots, it could be a user-level alias. 572 * this is also done in res_query() since we are not the only 573 * function that looks up host names. 574 */ 575 if (!strchr(name, '.') && (cp = __hostalias(name))) 576 name = cp; 577 578 /* 579 * disallow names consisting only of digits/dots, unless 580 * they end in a dot. 581 */ 582 if (isdigit((u_char) name[0])) 583 for (cp = name;; ++cp) { 584 if (!*cp) { 585 if (*--cp == '.') 586 break; 587 /* 588 * All-numeric, no dot at the end. 589 * Fake up a hostent as if we'd actually 590 * done a lookup. 591 */ 592 if (inet_pton(af, name, 593 (char *)(void *)host_addr) <= 0) { 594 h_errno = HOST_NOT_FOUND; 595 return (NULL); 596 } 597 strncpy(hostbuf, name, MAXDNAME); 598 hostbuf[MAXDNAME] = '\0'; 599 bp = hostbuf + MAXDNAME; 600 ep = hostbuf + sizeof hostbuf; 601 host.h_name = hostbuf; 602 host.h_aliases = host_aliases; 603 host_aliases[0] = NULL; 604 h_addr_ptrs[0] = (char *)(void *)host_addr; 605 h_addr_ptrs[1] = NULL; 606 host.h_addr_list = h_addr_ptrs; 607 if (_res.options & RES_USE_INET6) 608 map_v4v6_hostent(&host, &bp, ep); 609 h_errno = NETDB_SUCCESS; 610 return (&host); 611 } 612 if (!isdigit((u_char) *cp) && *cp != '.') 613 break; 614 } 615 if ((isxdigit((u_char) name[0]) && strchr(name, ':') != NULL) || 616 name[0] == ':') 617 for (cp = name;; ++cp) { 618 if (!*cp) { 619 if (*--cp == '.') 620 break; 621 /* 622 * All-IPv6-legal, no dot at the end. 623 * Fake up a hostent as if we'd actually 624 * done a lookup. 625 */ 626 if (inet_pton(af, name, 627 (char *)(void *)host_addr) <= 0) { 628 h_errno = HOST_NOT_FOUND; 629 return (NULL); 630 } 631 strncpy(hostbuf, name, MAXDNAME); 632 hostbuf[MAXDNAME] = '\0'; 633 bp = hostbuf + MAXDNAME; 634 ep = hostbuf + sizeof hostbuf; 635 host.h_name = hostbuf; 636 host.h_aliases = host_aliases; 637 host_aliases[0] = NULL; 638 h_addr_ptrs[0] = (char *)(void *)host_addr; 639 h_addr_ptrs[1] = NULL; 640 host.h_addr_list = h_addr_ptrs; 641 h_errno = NETDB_SUCCESS; 642 return (&host); 643 } 644 if (!isxdigit((u_char) *cp) && *cp != ':' && *cp != '.') 645 break; 646 } 647 648 hp = (struct hostent *)NULL; 649 h_errno = NETDB_INTERNAL; 650 if (nsdispatch(&hp, dtab, NSDB_HOSTS, "gethostbyname", 651 default_dns_files, name, strlen(name), af) != NS_SUCCESS) 652 return (struct hostent *)NULL; 653 h_errno = NETDB_SUCCESS; 654 return (hp); 655 } 656 657 struct hostent * 658 gethostbyaddr(addr, len, af) 659 const char *addr; /* XXX should have been def'd as u_char! */ 660 socklen_t len; 661 int af; 662 { 663 const u_char *uaddr = (const u_char *)addr; 664 int size; 665 struct hostent *hp; 666 static const ns_dtab dtab[] = { 667 NS_FILES_CB(_gethtbyaddr, NULL) 668 { NSSRC_DNS, _dns_gethtbyaddr, NULL }, /* force -DHESIOD */ 669 NS_NIS_CB(_yp_gethtbyaddr, NULL) 670 { 0 } 671 }; 672 673 _DIAGASSERT(addr != NULL); 674 675 if (af == AF_INET6 && len == IN6ADDRSZ && 676 (IN6_IS_ADDR_LINKLOCAL((const struct in6_addr *)(const void *)uaddr) || 677 IN6_IS_ADDR_SITELOCAL((const struct in6_addr *)(const void *)uaddr))) { 678 h_errno = HOST_NOT_FOUND; 679 return (NULL); 680 } 681 if (af == AF_INET6 && len == IN6ADDRSZ && 682 (IN6_IS_ADDR_V4MAPPED((const struct in6_addr *)(const void *)uaddr) || 683 IN6_IS_ADDR_V4COMPAT((const struct in6_addr *)(const void *)uaddr))) { 684 /* Unmap. */ 685 addr += IN6ADDRSZ - INADDRSZ; 686 uaddr += IN6ADDRSZ - INADDRSZ; 687 af = AF_INET; 688 len = INADDRSZ; 689 } 690 switch (af) { 691 case AF_INET: 692 size = INADDRSZ; 693 break; 694 case AF_INET6: 695 size = IN6ADDRSZ; 696 break; 697 default: 698 errno = EAFNOSUPPORT; 699 h_errno = NETDB_INTERNAL; 700 return (NULL); 701 } 702 if (size != len) { 703 errno = EINVAL; 704 h_errno = NETDB_INTERNAL; 705 return (NULL); 706 } 707 hp = (struct hostent *)NULL; 708 h_errno = NETDB_INTERNAL; 709 if (nsdispatch(&hp, dtab, NSDB_HOSTS, "gethostbyaddr", 710 default_dns_files, uaddr, len, af) != NS_SUCCESS) 711 return (struct hostent *)NULL; 712 h_errno = NETDB_SUCCESS; 713 return (hp); 714 } 715 716 void 717 _sethtent(f) 718 int f; 719 { 720 if (!hostf) 721 hostf = fopen(_PATH_HOSTS, "r" ); 722 else 723 rewind(hostf); 724 stayopen = f; 725 } 726 727 void 728 _endhtent() 729 { 730 if (hostf && !stayopen) { 731 (void) fclose(hostf); 732 hostf = NULL; 733 } 734 } 735 736 struct hostent * 737 _gethtent() 738 { 739 char *p; 740 char *cp, **q; 741 int af, len; 742 743 if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) { 744 h_errno = NETDB_INTERNAL; 745 return (NULL); 746 } 747 again: 748 if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) { 749 h_errno = HOST_NOT_FOUND; 750 return (NULL); 751 } 752 if (*p == '#') 753 goto again; 754 if (!(cp = strpbrk(p, "#\n"))) 755 goto again; 756 *cp = '\0'; 757 if (!(cp = strpbrk(p, " \t"))) 758 goto again; 759 *cp++ = '\0'; 760 if (inet_pton(AF_INET6, p, (char *)(void *)host_addr) > 0) { 761 af = AF_INET6; 762 len = IN6ADDRSZ; 763 } else if (inet_pton(AF_INET, p, (char *)(void *)host_addr) > 0) { 764 if (_res.options & RES_USE_INET6) { 765 map_v4v6_address((char *)(void *)host_addr, 766 (char *)(void *)host_addr); 767 af = AF_INET6; 768 len = IN6ADDRSZ; 769 } else { 770 af = AF_INET; 771 len = INADDRSZ; 772 } 773 } else { 774 goto again; 775 } 776 /* if this is not something we're looking for, skip it. */ 777 if (host.h_addrtype != af) 778 goto again; 779 if (host.h_length != len) 780 goto again; 781 h_addr_ptrs[0] = (char *)(void *)host_addr; 782 h_addr_ptrs[1] = NULL; 783 host.h_addr_list = h_addr_ptrs; 784 host.h_length = len; 785 host.h_addrtype = af; 786 while (*cp == ' ' || *cp == '\t') 787 cp++; 788 host.h_name = cp; 789 q = host.h_aliases = host_aliases; 790 if ((cp = strpbrk(cp, " \t")) != NULL) 791 *cp++ = '\0'; 792 while (cp && *cp) { 793 if (*cp == ' ' || *cp == '\t') { 794 cp++; 795 continue; 796 } 797 if (q < &host_aliases[MAXALIASES - 1]) 798 *q++ = cp; 799 if ((cp = strpbrk(cp, " \t")) != NULL) 800 *cp++ = '\0'; 801 } 802 *q = NULL; 803 h_errno = NETDB_SUCCESS; 804 return (&host); 805 } 806 807 /*ARGSUSED*/ 808 int 809 _gethtbyname(rv, cb_data, ap) 810 void *rv; 811 void *cb_data; 812 va_list ap; 813 { 814 struct hostent *hp; 815 const char *name; 816 int af; 817 818 _DIAGASSERT(rv != NULL); 819 820 name = va_arg(ap, char *); 821 /* NOSTRICT skip len */(void)va_arg(ap, int); 822 af = va_arg(ap, int); 823 824 hp = NULL; 825 #if 0 826 if (_res.options & RES_USE_INET6) 827 hp = _gethtbyname2(name, AF_INET6); 828 if (hp==NULL) 829 hp = _gethtbyname2(name, AF_INET); 830 #else 831 hp = _gethtbyname2(name, af); 832 #endif 833 *((struct hostent **)rv) = hp; 834 if (hp == NULL) { 835 h_errno = HOST_NOT_FOUND; 836 return NS_NOTFOUND; 837 } 838 return NS_SUCCESS; 839 } 840 841 struct hostent * 842 _gethtbyname2(name, af) 843 const char *name; 844 int af; 845 { 846 struct hostent *p; 847 char *tmpbuf, *ptr, **cp; 848 int num; 849 size_t len; 850 851 _DIAGASSERT(name != NULL); 852 853 _sethtent(0); 854 ptr = tmpbuf = NULL; 855 num = 0; 856 while ((p = _gethtent()) != NULL && num < MAXADDRS) { 857 if (p->h_addrtype != af) 858 continue; 859 if (strcasecmp(p->h_name, name) != 0) { 860 for (cp = p->h_aliases; *cp != NULL; cp++) 861 if (strcasecmp(*cp, name) == 0) 862 break; 863 if (*cp == NULL) continue; 864 } 865 866 if (num == 0) { 867 size_t bufsize; 868 char *src; 869 870 bufsize = strlen(p->h_name) + 2 + 871 MAXADDRS * p->h_length + 872 ALIGNBYTES; 873 for (cp = p->h_aliases; *cp != NULL; cp++) 874 bufsize += strlen(*cp) + 1; 875 876 if ((tmpbuf = malloc(bufsize)) == NULL) { 877 h_errno = NETDB_INTERNAL; 878 return NULL; 879 } 880 881 ptr = tmpbuf; 882 src = p->h_name; 883 while ((*ptr++ = *src++) != '\0'); 884 for (cp = p->h_aliases; *cp != NULL; cp++) { 885 src = *cp; 886 while ((*ptr++ = *src++) != '\0'); 887 } 888 *ptr++ = '\0'; 889 890 ptr = (char *)(void *)ALIGN(ptr); 891 } 892 893 (void)memcpy(ptr, p->h_addr_list[0], (size_t)p->h_length); 894 ptr += p->h_length; 895 num++; 896 } 897 _endhtent(); 898 if (num == 0) return NULL; 899 900 len = ptr - tmpbuf; 901 if (len > (sizeof(hostbuf) - ALIGNBYTES)) { 902 free(tmpbuf); 903 errno = ENOSPC; 904 h_errno = NETDB_INTERNAL; 905 return NULL; 906 } 907 ptr = memcpy((void *)ALIGN(hostbuf), tmpbuf, len); 908 free(tmpbuf); 909 910 host.h_name = ptr; 911 while (*ptr++); 912 913 cp = host_aliases; 914 while (*ptr) { 915 *cp++ = ptr; 916 while (*ptr++); 917 } 918 ptr++; 919 *cp = NULL; 920 921 ptr = (char *)(void *)ALIGN(ptr); 922 cp = h_addr_ptrs; 923 while (num--) { 924 *cp++ = ptr; 925 ptr += host.h_length; 926 } 927 *cp = NULL; 928 929 return (&host); 930 } 931 932 /*ARGSUSED*/ 933 int 934 _gethtbyaddr(rv, cb_data, ap) 935 void *rv; 936 void *cb_data; 937 va_list ap; 938 { 939 struct hostent *p; 940 const unsigned char *addr; 941 int len, af; 942 943 _DIAGASSERT(rv != NULL); 944 945 addr = va_arg(ap, unsigned char *); 946 len = va_arg(ap, int); 947 af = va_arg(ap, int); 948 949 host.h_length = len; 950 host.h_addrtype = af; 951 952 _sethtent(0); 953 while ((p = _gethtent()) != NULL) 954 if (p->h_addrtype == af && !memcmp(p->h_addr, addr, 955 (size_t)len)) 956 break; 957 _endhtent(); 958 *((struct hostent **)rv) = p; 959 if (p==NULL) { 960 h_errno = HOST_NOT_FOUND; 961 return NS_NOTFOUND; 962 } 963 return NS_SUCCESS; 964 } 965 966 static void 967 map_v4v6_address(src, dst) 968 const char *src; 969 char *dst; 970 { 971 u_char *p = (u_char *)dst; 972 char tmp[INADDRSZ]; 973 int i; 974 975 _DIAGASSERT(src != NULL); 976 _DIAGASSERT(dst != NULL); 977 978 /* Stash a temporary copy so our caller can update in place. */ 979 (void)memcpy(tmp, src, INADDRSZ); 980 /* Mark this ipv6 addr as a mapped ipv4. */ 981 for (i = 0; i < 10; i++) 982 *p++ = 0x00; 983 *p++ = 0xff; 984 *p++ = 0xff; 985 /* Retrieve the saved copy and we're done. */ 986 (void)memcpy((void *)p, tmp, INADDRSZ); 987 } 988 989 static void 990 map_v4v6_hostent(hp, bpp, ep) 991 struct hostent *hp; 992 char **bpp; 993 char *ep; 994 { 995 char **ap; 996 997 _DIAGASSERT(hp != NULL); 998 _DIAGASSERT(bpp != NULL); 999 _DIAGASSERT(ep != NULL); 1000 1001 if (hp->h_addrtype != AF_INET || hp->h_length != INADDRSZ) 1002 return; 1003 hp->h_addrtype = AF_INET6; 1004 hp->h_length = IN6ADDRSZ; 1005 for (ap = hp->h_addr_list; *ap; ap++) { 1006 int i = sizeof(align) - (size_t)((u_long)*bpp % sizeof(align)); 1007 1008 if (ep - *bpp < (i + IN6ADDRSZ)) { 1009 /* Out of memory. Truncate address list here. XXX */ 1010 *ap = NULL; 1011 return; 1012 } 1013 *bpp += i; 1014 map_v4v6_address(*ap, *bpp); 1015 *ap = *bpp; 1016 *bpp += IN6ADDRSZ; 1017 } 1018 } 1019 1020 #ifdef RESOLVSORT 1021 static void 1022 addrsort(ap, num) 1023 char **ap; 1024 int num; 1025 { 1026 int i, j; 1027 char **p; 1028 short aval[MAXADDRS]; 1029 int needsort = 0; 1030 1031 _DIAGASSERT(ap != NULL); 1032 1033 p = ap; 1034 for (i = 0; i < num; i++, p++) { 1035 for (j = 0 ; (unsigned)j < _res.nsort; j++) 1036 if (_res.sort_list[j].addr.s_addr == 1037 (((struct in_addr *)(void *)(*p))->s_addr & 1038 _res.sort_list[j].mask)) 1039 break; 1040 aval[i] = j; 1041 if (needsort == 0 && i > 0 && j < aval[i-1]) 1042 needsort = i; 1043 } 1044 if (!needsort) 1045 return; 1046 1047 while (needsort < num) { 1048 for (j = needsort - 1; j >= 0; j--) { 1049 if (aval[j] > aval[j+1]) { 1050 char *hp; 1051 1052 i = aval[j]; 1053 aval[j] = aval[j+1]; 1054 aval[j+1] = i; 1055 1056 hp = ap[j]; 1057 ap[j] = ap[j+1]; 1058 ap[j+1] = hp; 1059 } else 1060 break; 1061 } 1062 needsort++; 1063 } 1064 } 1065 #endif 1066 1067 #if defined(BSD43_BSD43_NFS) || defined(sun) 1068 /* XXX: should we remove this cruft? - lukem */ 1069 /* some libc's out there are bound internally to these names (UMIPS) */ 1070 void 1071 ht_sethostent(stayopen) 1072 int stayopen; 1073 { 1074 _sethtent(stayopen); 1075 } 1076 1077 void 1078 ht_endhostent() 1079 { 1080 _endhtent(); 1081 } 1082 1083 struct hostent * 1084 ht_gethostbyname(name) 1085 char *name; 1086 { 1087 return (_gethtbyname(name)); 1088 } 1089 1090 struct hostent * 1091 ht_gethostbyaddr(addr, len, af) 1092 const char *addr; 1093 int len, af; 1094 { 1095 return (_gethtbyaddr(addr, len, af)); 1096 } 1097 1098 struct hostent * 1099 gethostent() 1100 { 1101 return (_gethtent()); 1102 } 1103 1104 void 1105 dns_service() 1106 { 1107 return; 1108 } 1109 1110 int 1111 dn_skipname(comp_dn, eom) 1112 const u_char *comp_dn, *eom; 1113 { 1114 return (__dn_skipname(comp_dn, eom)); 1115 } 1116 #endif /*old-style libc with yp junk in it*/ 1117 1118 /*ARGSUSED*/ 1119 int 1120 _dns_gethtbyname(rv, cb_data, ap) 1121 void *rv; 1122 void *cb_data; 1123 va_list ap; 1124 { 1125 querybuf buf; 1126 int n, type; 1127 struct hostent *hp; 1128 const char *name; 1129 int af; 1130 1131 _DIAGASSERT(rv != NULL); 1132 1133 name = va_arg(ap, char *); 1134 /* NOSTRICT skip len */(void)va_arg(ap, int); 1135 af = va_arg(ap, int); 1136 1137 switch (af) { 1138 case AF_INET: 1139 type = T_A; 1140 break; 1141 case AF_INET6: 1142 type = T_AAAA; 1143 break; 1144 default: 1145 return NS_UNAVAIL; 1146 } 1147 if ((n = res_search(name, C_IN, type, buf.buf, sizeof(buf))) < 0) { 1148 dprintf("res_search failed (%d)\n", n); 1149 return NS_NOTFOUND; 1150 } 1151 hp = getanswer(&buf, n, name, type); 1152 if (hp == NULL) 1153 switch (h_errno) { 1154 case HOST_NOT_FOUND: 1155 return NS_NOTFOUND; 1156 case TRY_AGAIN: 1157 return NS_TRYAGAIN; 1158 default: 1159 return NS_UNAVAIL; 1160 } 1161 *((struct hostent **)rv) = hp; 1162 return NS_SUCCESS; 1163 } 1164 1165 /*ARGSUSED*/ 1166 int 1167 _dns_gethtbyaddr(rv, cb_data, ap) 1168 void *rv; 1169 void *cb_data; 1170 va_list ap; 1171 { 1172 char qbuf[MAXDNAME + 1], *qp; 1173 int n; 1174 querybuf buf; 1175 struct hostent *hp; 1176 const unsigned char *uaddr; 1177 int len, af, advance; 1178 1179 _DIAGASSERT(rv != NULL); 1180 1181 uaddr = va_arg(ap, unsigned char *); 1182 len = va_arg(ap, int); 1183 af = va_arg(ap, int); 1184 1185 switch (af) { 1186 case AF_INET: 1187 (void)snprintf(qbuf, sizeof(qbuf), "%u.%u.%u.%u.in-addr.arpa", 1188 (uaddr[3] & 0xff), (uaddr[2] & 0xff), 1189 (uaddr[1] & 0xff), (uaddr[0] & 0xff)); 1190 break; 1191 1192 case AF_INET6: 1193 qp = qbuf; 1194 for (n = IN6ADDRSZ - 1; n >= 0; n--) { 1195 advance = sprintf(qp, "%x.%x.", uaddr[n] & 0xf, 1196 ((unsigned int)uaddr[n] >> 4) & 0xf); 1197 if (advance > 0 && 1198 qp + advance < qbuf + sizeof(qbuf) - 1) 1199 qp += advance; 1200 else 1201 return NS_NOTFOUND; 1202 } 1203 strlcat(qbuf, "ip6.arpa", sizeof(qbuf)); 1204 break; 1205 default: 1206 abort(); 1207 } 1208 1209 n = res_query(qbuf, C_IN, T_PTR, (u_char *)(void *)&buf, sizeof(buf)); 1210 if (n < 0 && af == AF_INET6) { 1211 *qp = '\0'; 1212 strlcat(qbuf, "ip6.int", sizeof(qbuf)); 1213 n = res_query(qbuf, C_IN, T_PTR, (u_char *)(void *)&buf, 1214 sizeof(buf)); 1215 } 1216 if (n < 0) { 1217 dprintf("res_query failed (%d)\n", n); 1218 return NS_NOTFOUND; 1219 } 1220 hp = getanswer(&buf, n, qbuf, T_PTR); 1221 if (hp == NULL) 1222 switch (h_errno) { 1223 case HOST_NOT_FOUND: 1224 return NS_NOTFOUND; 1225 case TRY_AGAIN: 1226 return NS_TRYAGAIN; 1227 default: 1228 return NS_UNAVAIL; 1229 } 1230 hp->h_addrtype = af; 1231 hp->h_length = len; 1232 (void)memcpy(host_addr, uaddr, (size_t)len); 1233 h_addr_ptrs[0] = (char *)(void *)host_addr; 1234 h_addr_ptrs[1] = NULL; 1235 if (af == AF_INET && (_res.options & RES_USE_INET6)) { 1236 map_v4v6_address((char *)(void *)host_addr, 1237 (char *)(void *)host_addr); 1238 hp->h_addrtype = AF_INET6; 1239 hp->h_length = IN6ADDRSZ; 1240 } 1241 1242 *((struct hostent **)rv) = hp; 1243 h_errno = NETDB_SUCCESS; 1244 return NS_SUCCESS; 1245 } 1246 1247 #ifdef YP 1248 /*ARGSUSED*/ 1249 struct hostent * 1250 _yphostent(line, af) 1251 char *line; 1252 int af; 1253 { 1254 static struct in_addr host_addrs[MAXADDRS]; 1255 static struct in6_addr host6_addrs[MAXADDRS]; 1256 char *p = line; 1257 char *cp, **q; 1258 char **hap; 1259 int addrok; 1260 int more; 1261 int naddrs; 1262 1263 _DIAGASSERT(line != NULL); 1264 1265 host.h_name = NULL; 1266 host.h_addr_list = h_addr_ptrs; 1267 host.h_addrtype = af; 1268 switch (af) { 1269 case AF_INET: 1270 host.h_length = INADDRSZ; 1271 break; 1272 case AF_INET6: 1273 host.h_length = IN6ADDRSZ; 1274 break; 1275 default: 1276 return (NULL); 1277 } 1278 hap = h_addr_ptrs; 1279 q = host.h_aliases = host_aliases; 1280 naddrs = 0; 1281 1282 nextline: 1283 /* check for host_addrs overflow */ 1284 if (naddrs >= sizeof(host_addrs) / sizeof(host_addrs[0])) 1285 goto done; 1286 if (naddrs >= sizeof(host6_addrs) / sizeof(host6_addrs[0])) 1287 goto done; 1288 1289 more = 0; 1290 cp = strpbrk(p, " \t"); 1291 if (cp == NULL) 1292 goto done; 1293 *cp++ = '\0'; 1294 1295 /* p has should have an address */ 1296 switch (af) { 1297 case AF_INET: 1298 addrok = inet_aton(p, &host_addrs[naddrs]); 1299 break; 1300 case AF_INET6: 1301 addrok = inet_pton(af, p, &host6_addrs[naddrs]); 1302 break; 1303 } 1304 if (addrok != 1) { 1305 /* skip to the next line */ 1306 while (cp && *cp) { 1307 if (*cp == '\n') { 1308 cp++; 1309 goto nextline; 1310 } 1311 cp++; 1312 } 1313 1314 goto done; 1315 } 1316 1317 switch (af) { 1318 case AF_INET: 1319 *hap++ = (char *)(void *)&host_addrs[naddrs++]; 1320 break; 1321 case AF_INET6: 1322 *hap++ = (char *)(void *)&host6_addrs[naddrs++]; 1323 break; 1324 } 1325 1326 while (*cp == ' ' || *cp == '\t') 1327 cp++; 1328 p = cp; 1329 cp = strpbrk(p, " \t\n"); 1330 if (cp != NULL) { 1331 if (*cp == '\n') 1332 more = 1; 1333 *cp++ = '\0'; 1334 } 1335 if (!host.h_name) 1336 host.h_name = p; 1337 else if (strcmp(host.h_name, p)==0) 1338 ; 1339 else if (q < &host_aliases[MAXALIASES - 1]) 1340 *q++ = p; 1341 p = cp; 1342 if (more) 1343 goto nextline; 1344 1345 while (cp && *cp) { 1346 if (*cp == ' ' || *cp == '\t') { 1347 cp++; 1348 continue; 1349 } 1350 if (*cp == '\n') { 1351 cp++; 1352 goto nextline; 1353 } 1354 if (q < &host_aliases[MAXALIASES - 1]) 1355 *q++ = cp; 1356 cp = strpbrk(cp, " \t"); 1357 if (cp != NULL) 1358 *cp++ = '\0'; 1359 } 1360 1361 done: 1362 if (host.h_name == NULL) 1363 return (NULL); 1364 *q = NULL; 1365 *hap = NULL; 1366 return (&host); 1367 } 1368 1369 /*ARGSUSED*/ 1370 int 1371 _yp_gethtbyaddr(rv, cb_data, ap) 1372 void *rv; 1373 void *cb_data; 1374 va_list ap; 1375 { 1376 struct hostent *hp = (struct hostent *)NULL; 1377 static char *__ypcurrent; 1378 int __ypcurrentlen, r; 1379 char name[INET6_ADDRSTRLEN]; /* XXX enough? */ 1380 const unsigned char *uaddr; 1381 int af; 1382 const char *map; 1383 1384 _DIAGASSERT(rv != NULL); 1385 1386 uaddr = va_arg(ap, unsigned char *); 1387 /* NOSTRICT skip len */(void)va_arg(ap, int); 1388 af = va_arg(ap, int); 1389 1390 if (!__ypdomain) { 1391 if (_yp_check(&__ypdomain) == 0) 1392 return NS_UNAVAIL; 1393 } 1394 /* 1395 * XXX unfortunately, we cannot support IPv6 extended scoped address 1396 * notation here. gethostbyaddr() is not scope-aware. too bad. 1397 */ 1398 if (inet_ntop(af, uaddr, name, sizeof(name)) == NULL) 1399 return NS_UNAVAIL; 1400 if (__ypcurrent) 1401 free(__ypcurrent); 1402 __ypcurrent = NULL; 1403 switch (af) { 1404 case AF_INET: 1405 map = "hosts.byaddr"; 1406 break; 1407 default: 1408 map = "ipnodes.byaddr"; 1409 break; 1410 } 1411 r = yp_match(__ypdomain, map, name, 1412 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 1413 if (r==0) 1414 hp = _yphostent(__ypcurrent, af); 1415 if (hp==NULL) { 1416 h_errno = HOST_NOT_FOUND; 1417 return NS_NOTFOUND; 1418 } 1419 *((struct hostent **)rv) = hp; 1420 return NS_SUCCESS; 1421 } 1422 1423 /*ARGSUSED*/ 1424 int 1425 _yp_gethtbyname(rv, cb_data, ap) 1426 void *rv; 1427 void *cb_data; 1428 va_list ap; 1429 { 1430 struct hostent *hp = (struct hostent *)NULL; 1431 static char *__ypcurrent; 1432 int __ypcurrentlen, r; 1433 const char *name; 1434 int af; 1435 const char *map; 1436 1437 _DIAGASSERT(rv != NULL); 1438 1439 name = va_arg(ap, char *); 1440 /* NOSTRICT skip len */(void)va_arg(ap, int); 1441 af = va_arg(ap, int); 1442 1443 if (!__ypdomain) { 1444 if (_yp_check(&__ypdomain) == 0) 1445 return NS_UNAVAIL; 1446 } 1447 if (__ypcurrent) 1448 free(__ypcurrent); 1449 __ypcurrent = NULL; 1450 switch (af) { 1451 case AF_INET: 1452 map = "hosts.byname"; 1453 break; 1454 default: 1455 map = "ipnodes.byname"; 1456 break; 1457 } 1458 r = yp_match(__ypdomain, map, name, 1459 (int)strlen(name), &__ypcurrent, &__ypcurrentlen); 1460 if (r==0) 1461 hp = _yphostent(__ypcurrent, af); 1462 if (hp==NULL) { 1463 h_errno = HOST_NOT_FOUND; 1464 return NS_NOTFOUND; 1465 } 1466 *((struct hostent **)rv) = hp; 1467 return NS_SUCCESS; 1468 } 1469 #endif 1470
Indexes created Mon Sep 29 21:09:56 GMT 2025