getnetnamadr.c revision 1.27
1 /* $NetBSD: getnetnamadr.c,v 1.27 2003/08/07 16:43:09 agc Exp $ */ 2 3 /* Copyright (c) 1993 Carlos Leandro and Rui Salgueiro 4 * Dep. Matematica Universidade de Coimbra, Portugal, Europe 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 */ 10 /* 11 * Copyright (c) 1983, 1993 12 * The Regents of the University of California. All rights reserved. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #if defined(LIBC_SCCS) && !defined(lint) 41 #if 0 42 static char sccsid[] = "@(#)getnetbyaddr.c 8.1 (Berkeley) 6/4/93"; 43 static char sccsid_[] = "from getnetnamadr.c 1.4 (Coimbra) 93/06/03"; 44 static char rcsid[] = "Id: getnetnamadr.c,v 8.8 1997/06/01 20:34:37 vixie Exp "; 45 #else 46 __RCSID("$NetBSD: getnetnamadr.c,v 1.27 2003/08/07 16:43:09 agc Exp $"); 47 #endif 48 #endif /* LIBC_SCCS and not lint */ 49 50 #include "namespace.h" 51 #include <sys/types.h> 52 #include <sys/param.h> 53 #include <sys/socket.h> 54 #include <netinet/in.h> 55 #include <arpa/inet.h> 56 #include <arpa/nameser.h> 57 58 #include <assert.h> 59 #include <ctype.h> 60 #include <errno.h> 61 #include <netdb.h> 62 #include <nsswitch.h> 63 #include <resolv.h> 64 #include <stdarg.h> 65 #include <stdio.h> 66 #include <stdlib.h> 67 #include <string.h> 68 69 #ifdef YP 70 #include <rpc/rpc.h> 71 #include <rpcsvc/yp_prot.h> 72 #include <rpcsvc/ypclnt.h> 73 #endif 74 75 #ifdef __weak_alias 76 __weak_alias(getnetbyaddr,_getnetbyaddr) 77 __weak_alias(getnetbyname,_getnetbyname) 78 #endif 79 80 extern int _net_stayopen; 81 82 #define BYADDR 0 83 #define BYNAME 1 84 #define MAXALIASES 35 85 86 #define MAXPACKET (64*1024) 87 88 typedef union { 89 HEADER hdr; 90 u_char buf[MAXPACKET]; 91 } querybuf; 92 93 typedef union { 94 long al; 95 char ac; 96 } align; 97 98 #ifdef YP 99 static char *__ypdomain; 100 static char *__ypcurrent; 101 static int __ypcurrentlen; 102 #endif 103 104 static struct netent net_entry; 105 static char *net_aliases[MAXALIASES]; 106 107 static struct netent *getnetanswer __P((querybuf *, int, int)); 108 int _files_getnetbyaddr __P((void *, void *, va_list)); 109 int _files_getnetbyname __P((void *, void *, va_list)); 110 int _dns_getnetbyaddr __P((void *, void *, va_list)); 111 int _dns_getnetbyname __P((void *, void *, va_list)); 112 #ifdef YP 113 int _yp_getnetbyaddr __P((void *, void *, va_list)); 114 int _yp_getnetbyname __P((void *, void *, va_list)); 115 struct netent *_ypnetent __P((char *)); 116 #endif 117 118 static struct netent * 119 getnetanswer(answer, anslen, net_i) 120 querybuf *answer; 121 int anslen; 122 int net_i; 123 { 124 HEADER *hp; 125 u_char *cp; 126 int n; 127 u_char *eom; 128 int type, class, ancount, qdcount, haveanswer, i, nchar; 129 char aux1[MAXDNAME], aux2[MAXDNAME], ans[MAXDNAME]; 130 char *in, *st, *pauxt, *bp, **ap; 131 char *paux1 = &aux1[0], *paux2 = &aux2[0], *ep; 132 static char netbuf[PACKETSZ]; 133 134 _DIAGASSERT(answer != NULL); 135 136 /* 137 * find first satisfactory answer 138 * 139 * answer --> +------------+ ( MESSAGE ) 140 * | Header | 141 * +------------+ 142 * | Question | the question for the name server 143 * +------------+ 144 * | Answer | RRs answering the question 145 * +------------+ 146 * | Authority | RRs pointing toward an authority 147 * | Additional | RRs holding additional information 148 * +------------+ 149 */ 150 eom = answer->buf + anslen; 151 hp = &answer->hdr; 152 ancount = ntohs(hp->ancount); /* #/records in the answer section */ 153 qdcount = ntohs(hp->qdcount); /* #/entries in the question section */ 154 bp = netbuf; 155 ep = netbuf + sizeof(netbuf); 156 cp = answer->buf + HFIXEDSZ; 157 if (!qdcount) { 158 if (hp->aa) 159 h_errno = HOST_NOT_FOUND; 160 else 161 h_errno = TRY_AGAIN; 162 return (NULL); 163 } 164 while (qdcount-- > 0) { 165 n = __dn_skipname(cp, eom); 166 if (n < 0 || (cp + n + QFIXEDSZ) > eom) { 167 h_errno = NO_RECOVERY; 168 return(NULL); 169 } 170 cp += n + QFIXEDSZ; 171 } 172 ap = net_aliases; 173 *ap = NULL; 174 net_entry.n_aliases = net_aliases; 175 haveanswer = 0; 176 while (--ancount >= 0 && cp < eom) { 177 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 178 if ((n < 0) || !res_dnok(bp)) 179 break; 180 cp += n; 181 ans[0] = '\0'; 182 (void)strlcpy(ans, bp, sizeof(ans)); 183 GETSHORT(type, cp); 184 GETSHORT(class, cp); 185 cp += INT32SZ; /* TTL */ 186 GETSHORT(n, cp); 187 if (class == C_IN && type == T_PTR) { 188 n = dn_expand(answer->buf, eom, cp, bp, ep - bp); 189 if ((n < 0) || !res_hnok(bp)) { 190 cp += n; 191 return (NULL); 192 } 193 cp += n; 194 *ap++ = bp; 195 bp += strlen(bp) + 1; 196 net_entry.n_addrtype = 197 (class == C_IN) ? AF_INET : AF_UNSPEC; 198 haveanswer++; 199 } 200 } 201 if (haveanswer) { 202 *ap = NULL; 203 switch (net_i) { 204 case BYADDR: 205 net_entry.n_name = *net_entry.n_aliases; 206 net_entry.n_net = 0L; 207 break; 208 case BYNAME: 209 ap = net_entry.n_aliases; 210 next_alias: 211 in = *ap++; 212 if (in == NULL) { 213 h_errno = HOST_NOT_FOUND; 214 return (NULL); 215 } 216 net_entry.n_name = ans; 217 aux2[0] = '\0'; 218 for (i = 0; i < 4; i++) { 219 for (st = in, nchar = 0; 220 isdigit((unsigned char)*st); 221 st++, nchar++) 222 ; 223 if (*st != '.' || nchar == 0 || nchar > 3) 224 goto next_alias; 225 if (i != 0) 226 nchar++; 227 (void)strlcpy(paux1, in, (size_t)nchar); 228 paux1[nchar] = '\0'; 229 pauxt = paux2; 230 paux2 = strcat(paux1, paux2); 231 paux1 = pauxt; 232 in = ++st; 233 } 234 net_entry.n_net = inet_network(paux2); 235 break; 236 } 237 if (strcasecmp(in, "IN-ADDR.ARPA") != 0) 238 goto next_alias; 239 net_entry.n_aliases++; 240 return (&net_entry); 241 } 242 h_errno = TRY_AGAIN; 243 return (NULL); 244 } 245 246 /*ARGSUSED*/ 247 int 248 _files_getnetbyaddr(rv, cb_data, ap) 249 void *rv; 250 void *cb_data; 251 va_list ap; 252 { 253 struct netent *p; 254 unsigned long net; 255 int type; 256 257 _DIAGASSERT(rv != NULL); 258 259 net = va_arg(ap, unsigned long); 260 type = va_arg(ap, int); 261 262 setnetent(_net_stayopen); 263 while ((p = getnetent()) != NULL) 264 if (p->n_addrtype == type && p->n_net == net) 265 break; 266 if (!_net_stayopen) 267 endnetent(); 268 *((struct netent **)rv) = p; 269 if (p==NULL) { 270 h_errno = HOST_NOT_FOUND; 271 return NS_NOTFOUND; 272 } 273 return NS_SUCCESS; 274 } 275 276 /*ARGSUSED*/ 277 int 278 _dns_getnetbyaddr(rv, cb_data, ap) 279 void *rv; 280 void *cb_data; 281 va_list ap; 282 { 283 unsigned int netbr[4]; 284 int nn, anslen; 285 querybuf *buf; 286 char qbuf[MAXDNAME]; 287 unsigned long net2; 288 struct netent *np; 289 unsigned long net; 290 int type; 291 292 _DIAGASSERT(rv != NULL); 293 294 net = va_arg(ap, unsigned long); 295 type = va_arg(ap, int); 296 297 if (type != AF_INET) 298 return NS_UNAVAIL; 299 300 for (nn = 4, net2 = net; net2; net2 >>= 8) 301 netbr[--nn] = (unsigned int)(net2 & 0xff); 302 switch (nn) { 303 default: 304 return NS_UNAVAIL; 305 case 3: /* Class A */ 306 snprintf(qbuf, sizeof(qbuf), "0.0.0.%u.in-addr.arpa", netbr[3]); 307 break; 308 case 2: /* Class B */ 309 snprintf(qbuf, sizeof(qbuf), "0.0.%u.%u.in-addr.arpa", 310 netbr[3], netbr[2]); 311 break; 312 case 1: /* Class C */ 313 snprintf(qbuf, sizeof(qbuf), "0.%u.%u.%u.in-addr.arpa", 314 netbr[3], netbr[2], netbr[1]); 315 break; 316 case 0: /* Class D - E */ 317 snprintf(qbuf, sizeof(qbuf), "%u.%u.%u.%u.in-addr.arpa", 318 netbr[3], netbr[2], netbr[1], netbr[0]); 319 break; 320 } 321 buf = malloc(sizeof(*buf)); 322 if (buf == NULL) { 323 h_errno = NETDB_INTERNAL; 324 return NS_NOTFOUND; 325 } 326 anslen = res_query(qbuf, C_IN, T_PTR, buf->buf, sizeof(buf->buf)); 327 if (anslen < 0) { 328 free(buf); 329 #ifdef DEBUG 330 if (_res.options & RES_DEBUG) 331 printf("res_query failed\n"); 332 #endif 333 return NS_NOTFOUND; 334 } 335 np = getnetanswer(buf, anslen, BYADDR); 336 free(buf); 337 if (np) { 338 /* maybe net should be unsigned? */ 339 unsigned long u_net = net; 340 341 /* Strip trailing zeros */ 342 while ((u_net & 0xff) == 0 && u_net != 0) 343 u_net >>= 8; 344 np->n_net = u_net; 345 } 346 *((struct netent **)rv) = np; 347 if (np == NULL) { 348 h_errno = HOST_NOT_FOUND; 349 return NS_NOTFOUND; 350 } 351 return NS_SUCCESS; 352 } 353 354 355 struct netent * 356 getnetbyaddr(net, net_type) 357 u_long net; 358 int net_type; 359 { 360 struct netent *np; 361 static const ns_dtab dtab[] = { 362 NS_FILES_CB(_files_getnetbyaddr, NULL) 363 { NSSRC_DNS, _dns_getnetbyaddr, NULL }, /* force -DHESIOD */ 364 NS_NIS_CB(_yp_getnetbyaddr, NULL) 365 { 0 } 366 }; 367 368 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 369 h_errno = NETDB_INTERNAL; 370 return (NULL); 371 } 372 373 np = NULL; 374 h_errno = NETDB_INTERNAL; 375 if (nsdispatch(&np, dtab, NSDB_NETWORKS, "getnetbyaddr", __nsdefaultsrc, 376 net, net_type) != NS_SUCCESS) 377 return (NULL); 378 h_errno = NETDB_SUCCESS; 379 return (np); 380 } 381 382 /*ARGSUSED*/ 383 int 384 _files_getnetbyname(rv, cb_data, ap) 385 void *rv; 386 void *cb_data; 387 va_list ap; 388 { 389 struct netent *p; 390 char **cp; 391 const char *name; 392 393 _DIAGASSERT(rv != NULL); 394 395 name = va_arg(ap, const char *); 396 setnetent(_net_stayopen); 397 while ((p = getnetent()) != NULL) { 398 if (strcasecmp(p->n_name, name) == 0) 399 break; 400 for (cp = p->n_aliases; *cp != 0; cp++) 401 if (strcasecmp(*cp, name) == 0) 402 goto found; 403 } 404 found: 405 if (!_net_stayopen) 406 endnetent(); 407 *((struct netent **)rv) = p; 408 if (p==NULL) { 409 h_errno = HOST_NOT_FOUND; 410 return NS_NOTFOUND; 411 } 412 return NS_SUCCESS; 413 } 414 415 /*ARGSUSED*/ 416 int 417 _dns_getnetbyname(rv, cb_data, ap) 418 void *rv; 419 void *cb_data; 420 va_list ap; 421 { 422 int anslen; 423 querybuf *buf; 424 char qbuf[MAXDNAME]; 425 struct netent *np; 426 const char *net; 427 428 _DIAGASSERT(rv != NULL); 429 430 net = va_arg(ap, const char *); 431 strlcpy(&qbuf[0], net, sizeof(qbuf)); 432 buf = malloc(sizeof(*buf)); 433 if (buf == NULL) { 434 h_errno = NETDB_INTERNAL; 435 return NS_NOTFOUND; 436 } 437 anslen = res_search(qbuf, C_IN, T_PTR, buf->buf, sizeof(buf->buf)); 438 if (anslen < 0) { 439 free(buf); 440 #ifdef DEBUG 441 if (_res.options & RES_DEBUG) 442 printf("res_search failed\n"); 443 #endif 444 return NS_NOTFOUND; 445 } 446 np = getnetanswer(buf, anslen, BYNAME); 447 free(buf); 448 *((struct netent **)rv) = np; 449 if (np == NULL) { 450 h_errno = HOST_NOT_FOUND; 451 return NS_NOTFOUND; 452 } 453 return NS_SUCCESS; 454 } 455 456 struct netent * 457 getnetbyname(net) 458 const char *net; 459 { 460 struct netent *np; 461 static const ns_dtab dtab[] = { 462 NS_FILES_CB(_files_getnetbyname, NULL) 463 { NSSRC_DNS, _dns_getnetbyname, NULL }, /* force -DHESIOD */ 464 NS_NIS_CB(_yp_getnetbyname, NULL) 465 { 0 } 466 }; 467 468 _DIAGASSERT(net != NULL); 469 470 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 471 h_errno = NETDB_INTERNAL; 472 return (NULL); 473 } 474 475 np = NULL; 476 h_errno = NETDB_INTERNAL; 477 if (nsdispatch(&np, dtab, NSDB_NETWORKS, "getnetbyname", __nsdefaultsrc, 478 net) != NS_SUCCESS) 479 return (NULL); 480 h_errno = NETDB_SUCCESS; 481 return (np); 482 } 483 484 #ifdef YP 485 /*ARGSUSED*/ 486 int 487 _yp_getnetbyaddr(rv, cb_data, ap) 488 void *rv; 489 void *cb_data; 490 va_list ap; 491 { 492 struct netent *np; 493 char qbuf[MAXDNAME]; 494 unsigned int netbr[4]; 495 unsigned long net, net2; 496 int type, r; 497 498 _DIAGASSERT(rv != NULL); 499 500 net = va_arg(ap, unsigned long); 501 type = va_arg(ap, int); 502 503 if (type != AF_INET) 504 return NS_UNAVAIL; 505 506 if (!__ypdomain) { 507 if (_yp_check(&__ypdomain) == 0) 508 return NS_UNAVAIL; 509 } 510 np = NULL; 511 if (__ypcurrent) 512 free(__ypcurrent); 513 __ypcurrent = NULL; 514 for (r = 4, net2 = net; net2; net2 >>= 8) 515 netbr[--r] = (unsigned int)(net2 & 0xff); 516 switch (r) { 517 default: 518 return NS_UNAVAIL; 519 case 3: /* Class A */ 520 snprintf(qbuf, sizeof(qbuf), "%u", netbr[0]); 521 break; 522 case 2: /* Class B */ 523 snprintf(qbuf, sizeof(qbuf), "%u.%u", netbr[0], netbr[1]); 524 break; 525 case 1: /* Class C */ 526 snprintf(qbuf, sizeof(qbuf), "%u.%u.%u", netbr[0], netbr[1], 527 netbr[2]); 528 break; 529 case 0: /* Class D - E */ 530 snprintf(qbuf, sizeof(qbuf), "%u.%u.%u.%u", netbr[0], netbr[1], 531 netbr[2], netbr[3]); 532 break; 533 } 534 r = yp_match(__ypdomain, "networks.byaddr", qbuf, (int)strlen(qbuf), 535 &__ypcurrent, &__ypcurrentlen); 536 if (r == 0) 537 np = _ypnetent(__ypcurrent); 538 539 *((struct netent **)rv) = np; 540 if (np == NULL) { 541 h_errno = HOST_NOT_FOUND; 542 return NS_NOTFOUND; 543 } 544 return NS_SUCCESS; 545 546 } 547 548 int 549 /*ARGSUSED*/ 550 _yp_getnetbyname(rv, cb_data, ap) 551 void *rv; 552 void *cb_data; 553 va_list ap; 554 { 555 struct netent *np; 556 const char *name; 557 int r; 558 559 _DIAGASSERT(rv != NULL); 560 561 name = va_arg(ap, const char *); 562 563 if (!__ypdomain) { 564 if (_yp_check(&__ypdomain) == 0) 565 return NS_UNAVAIL; 566 } 567 np = NULL; 568 if (__ypcurrent) 569 free(__ypcurrent); 570 __ypcurrent = NULL; 571 r = yp_match(__ypdomain, "networks.byname", name, (int)strlen(name), 572 &__ypcurrent, &__ypcurrentlen); 573 if (r == 0) 574 np = _ypnetent(__ypcurrent); 575 576 *((struct netent **)rv) = np; 577 if (np == NULL) { 578 h_errno = HOST_NOT_FOUND; 579 return NS_NOTFOUND; 580 } 581 return NS_SUCCESS; 582 } 583 584 struct netent * 585 _ypnetent(line) 586 char *line; 587 { 588 char *cp, *p, **q; 589 590 _DIAGASSERT(line != NULL); 591 592 net_entry.n_name = line; 593 cp = strpbrk(line, " \t"); 594 if (cp == NULL) 595 return (NULL); 596 *cp++ = '\0'; 597 while (*cp == ' ' || *cp == '\t') 598 cp++; 599 p = strpbrk(cp, " \t"); 600 if (p != NULL) 601 *p++ = '\0'; 602 net_entry.n_net = inet_network(cp); 603 net_entry.n_addrtype = AF_INET; 604 q = net_entry.n_aliases = net_aliases; 605 if (p != NULL) { 606 cp = p; 607 while (cp && *cp) { 608 if (*cp == ' ' || *cp == '\t') { 609 cp++; 610 continue; 611 } 612 if (q < &net_aliases[MAXALIASES - 1]) 613 *q++ = cp; 614 cp = strpbrk(cp, " \t"); 615 if (cp != NULL) 616 *cp++ = '\0'; 617 } 618 } 619 *q = NULL; 620 621 return (&net_entry); 622 } 623 #endif 624
Indexes created Mon Sep 22 21:09:42 GMT 2025