getnetnamadr.c revision 1.15
1 /* $NetBSD: getnetnamadr.c,v 1.15 1999/05/03 15:17:13 christos 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. All advertising materials mentioning features or use of this software 23 * must display the following acknowledgement: 24 * This product includes software developed by the University of 25 * California, Berkeley and its contributors. 26 * 4. Neither the name of the University nor the names of its contributors 27 * may be used to endorse or promote products derived from this software 28 * without specific prior written permission. 29 * 30 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 31 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 32 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 33 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 34 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 35 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 36 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 37 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 38 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 39 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 40 * SUCH DAMAGE. 41 */ 42 43 #include <sys/cdefs.h> 44 #if defined(LIBC_SCCS) && !defined(lint) 45 #if 0 46 static char sccsid[] = "@(#)getnetbyaddr.c 8.1 (Berkeley) 6/4/93"; 47 static char sccsid_[] = "from getnetnamadr.c 1.4 (Coimbra) 93/06/03"; 48 static char rcsid[] = "Id: getnetnamadr.c,v 8.8 1997/06/01 20:34:37 vixie Exp "; 49 #else 50 __RCSID("$NetBSD: getnetnamadr.c,v 1.15 1999/05/03 15:17:13 christos Exp $"); 51 #endif 52 #endif /* LIBC_SCCS and not lint */ 53 54 #include "namespace.h" 55 #include <sys/types.h> 56 #include <sys/param.h> 57 #include <sys/socket.h> 58 #include <netinet/in.h> 59 #include <arpa/inet.h> 60 #include <arpa/nameser.h> 61 62 #include <ctype.h> 63 #include <errno.h> 64 #include <netdb.h> 65 #include <nsswitch.h> 66 #include <resolv.h> 67 #include <stdio.h> 68 #include <stdlib.h> 69 #include <string.h> 70 71 #ifdef __STDC__ 72 #include <stdarg.h> 73 #else 74 #include <varargs.h> 75 #endif 76 77 #ifdef YP 78 #include <rpc/rpc.h> 79 #include <rpcsvc/yp_prot.h> 80 #include <rpcsvc/ypclnt.h> 81 #endif 82 83 #ifdef __weak_alias 84 __weak_alias(getnetbyaddr,_getnetbyaddr); 85 __weak_alias(getnetbyname,_getnetbyname); 86 #endif 87 88 extern int h_errno; 89 extern int _net_stayopen; 90 91 #if defined(mips) && defined(SYSTYPE_BSD43) 92 extern int errno; 93 #endif 94 95 #define BYADDR 0 96 #define BYNAME 1 97 #define MAXALIASES 35 98 99 #if PACKETSZ > 1024 100 #define MAXPACKET PACKETSZ 101 #else 102 #define MAXPACKET 1024 103 #endif 104 105 typedef union { 106 HEADER hdr; 107 u_char buf[MAXPACKET]; 108 } querybuf; 109 110 typedef union { 111 long al; 112 char ac; 113 } align; 114 115 #ifdef YP 116 static char *__ypdomain; 117 static char *__ypcurrent; 118 static int __ypcurrentlen; 119 #endif 120 121 static struct netent net_entry; 122 static char *net_aliases[MAXALIASES]; 123 124 static struct netent *getnetanswer __P((querybuf *, int, int)); 125 int _getnetbyaddr __P((void *, void *, va_list)); 126 int _getnetbyname __P((void *, void *, va_list)); 127 int _dns_getnetbyaddr __P((void *, void *, va_list)); 128 int _dns_getnetbyname __P((void *, void *, va_list)); 129 #ifdef YP 130 int _yp_getnetbyaddr __P((void *, void *, va_list)); 131 int _yp_getnetbyname __P((void *, void *, va_list)); 132 struct netent *_ypnetent __P((char *)); 133 #endif 134 135 static struct netent * 136 getnetanswer(answer, anslen, net_i) 137 querybuf *answer; 138 int anslen; 139 int net_i; 140 { 141 142 HEADER *hp; 143 u_char *cp; 144 int n; 145 u_char *eom; 146 int type, class, buflen, ancount, qdcount, haveanswer, i, nchar; 147 char aux1[30], aux2[30], ans[30], *in, *st, *pauxt, *bp, **ap, 148 *paux1 = &aux1[0], *paux2 = &aux2[0], flag = 0; 149 static char netbuf[PACKETSZ]; 150 151 /* 152 * find first satisfactory answer 153 * 154 * answer --> +------------+ ( MESSAGE ) 155 * | Header | 156 * +------------+ 157 * | Question | the question for the name server 158 * +------------+ 159 * | Answer | RRs answering the question 160 * +------------+ 161 * | Authority | RRs pointing toward an authority 162 * | Additional | RRs holding additional information 163 * +------------+ 164 */ 165 eom = answer->buf + anslen; 166 hp = &answer->hdr; 167 ancount = ntohs(hp->ancount); /* #/records in the answer section */ 168 qdcount = ntohs(hp->qdcount); /* #/entries in the question section */ 169 bp = netbuf; 170 buflen = sizeof(netbuf); 171 cp = answer->buf + HFIXEDSZ; 172 if (!qdcount) { 173 if (hp->aa) 174 h_errno = HOST_NOT_FOUND; 175 else 176 h_errno = TRY_AGAIN; 177 return (NULL); 178 } 179 while (qdcount-- > 0) 180 cp += __dn_skipname(cp, eom) + QFIXEDSZ; 181 ap = net_aliases; 182 *ap = NULL; 183 net_entry.n_aliases = net_aliases; 184 haveanswer = 0; 185 while (--ancount >= 0 && cp < eom) { 186 n = dn_expand(answer->buf, eom, cp, bp, buflen); 187 if ((n < 0) || !res_dnok(bp)) 188 break; 189 cp += n; 190 ans[0] = '\0'; 191 (void)strcpy(&ans[0], bp); 192 GETSHORT(type, cp); 193 GETSHORT(class, cp); 194 cp += INT32SZ; /* TTL */ 195 GETSHORT(n, cp); 196 if (class == C_IN && type == T_PTR) { 197 n = dn_expand(answer->buf, eom, cp, bp, buflen); 198 if ((n < 0) || !res_hnok(bp)) { 199 cp += n; 200 return (NULL); 201 } 202 cp += n; 203 *ap++ = bp; 204 bp += strlen(bp) + 1; 205 net_entry.n_addrtype = 206 (class == C_IN) ? AF_INET : AF_UNSPEC; 207 haveanswer++; 208 } 209 } 210 if (haveanswer) { 211 *ap = NULL; 212 switch (net_i) { 213 case BYADDR: 214 net_entry.n_name = *net_entry.n_aliases; 215 net_entry.n_net = 0L; 216 break; 217 case BYNAME: 218 in = *net_entry.n_aliases; 219 net_entry.n_name = &ans[0]; 220 aux2[0] = '\0'; 221 for (i = 0; i < 4; i++) { 222 for (st = in, nchar = 0; 223 *st != '.'; 224 st++, nchar++) 225 ; 226 if (nchar != 1 || *in != '0' || flag) { 227 flag = 1; 228 (void)strncpy(paux1, 229 (i==0) ? in : in-1, 230 (size_t)((i==0) ? nchar : nchar+1)); 231 paux1[(i==0) ? nchar : nchar+1] = '\0'; 232 pauxt = paux2; 233 paux2 = strcat(paux1, paux2); 234 paux1 = pauxt; 235 } 236 in = ++st; 237 } 238 net_entry.n_net = inet_network(paux2); 239 break; 240 } 241 net_entry.n_aliases++; 242 return (&net_entry); 243 } 244 h_errno = TRY_AGAIN; 245 return (NULL); 246 } 247 248 /*ARGSUSED*/ 249 int 250 _getnetbyaddr(rv, cb_data, ap) 251 void *rv; 252 void *cb_data; 253 va_list ap; 254 { 255 struct netent *p; 256 unsigned long net; 257 int type; 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 net = va_arg(ap, unsigned long); 293 type = va_arg(ap, int); 294 295 if (type != AF_INET) 296 return NS_UNAVAIL; 297 298 for (nn = 4, net2 = net; net2; net2 >>= 8) 299 netbr[--nn] = (unsigned int)(net2 & 0xff); 300 switch (nn) { 301 default: 302 return NS_UNAVAIL; 303 case 3: /* Class A */ 304 sprintf(qbuf, "0.0.0.%u.in-addr.arpa", netbr[3]); 305 break; 306 case 2: /* Class B */ 307 sprintf(qbuf, "0.0.%u.%u.in-addr.arpa", netbr[3], netbr[2]); 308 break; 309 case 1: /* Class C */ 310 sprintf(qbuf, "0.%u.%u.%u.in-addr.arpa", netbr[3], netbr[2], 311 netbr[1]); 312 break; 313 case 0: /* Class D - E */ 314 sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa", netbr[3], netbr[2], 315 netbr[1], netbr[0]); 316 break; 317 } 318 anslen = res_query(qbuf, C_IN, T_PTR, (u_char *)(void *)&buf, 319 sizeof(buf)); 320 if (anslen < 0) { 321 #ifdef DEBUG 322 if (_res.options & RES_DEBUG) 323 printf("res_query failed\n"); 324 #endif 325 return NS_NOTFOUND; 326 } 327 np = getnetanswer(&buf, anslen, BYADDR); 328 if (np) { 329 /* maybe net should be unsigned? */ 330 unsigned long u_net = net; 331 332 /* Strip trailing zeros */ 333 while ((u_net & 0xff) == 0 && u_net != 0) 334 u_net >>= 8; 335 np->n_net = u_net; 336 } 337 *((struct netent **)rv) = np; 338 if (np == NULL) { 339 h_errno = HOST_NOT_FOUND; 340 return NS_NOTFOUND; 341 } 342 return NS_SUCCESS; 343 } 344 345 346 struct netent * 347 getnetbyaddr(net, net_type) 348 u_long net; 349 int net_type; 350 { 351 struct netent *np; 352 static const ns_dtab dtab[] = { 353 NS_FILES_CB(_getnetbyaddr, NULL) 354 { NSSRC_DNS, _dns_getnetbyaddr, NULL }, /* force -DHESIOD */ 355 NS_NIS_CB(_yp_getnetbyaddr, NULL) 356 { 0 } 357 }; 358 359 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 360 h_errno = NETDB_INTERNAL; 361 return (NULL); 362 } 363 364 np = NULL; 365 h_errno = NETDB_INTERNAL; 366 if (nsdispatch(&np, dtab, NSDB_NETWORKS, "getnetbyaddr", __nsdefaultsrc, 367 net, net_type) != NS_SUCCESS) 368 return (NULL); 369 h_errno = NETDB_SUCCESS; 370 return (np); 371 } 372 373 /*ARGSUSED*/ 374 int 375 _getnetbyname(rv, cb_data, ap) 376 void *rv; 377 void *cb_data; 378 va_list ap; 379 { 380 struct netent *p; 381 char **cp; 382 const char *name; 383 384 name = va_arg(ap, const char *); 385 setnetent(_net_stayopen); 386 while ((p = getnetent()) != NULL) { 387 if (strcasecmp(p->n_name, name) == 0) 388 break; 389 for (cp = p->n_aliases; *cp != 0; cp++) 390 if (strcasecmp(*cp, name) == 0) 391 goto found; 392 } 393 found: 394 if (!_net_stayopen) 395 endnetent(); 396 *((struct netent **)rv) = p; 397 if (p==NULL) { 398 h_errno = HOST_NOT_FOUND; 399 return NS_NOTFOUND; 400 } 401 return NS_SUCCESS; 402 } 403 404 /*ARGSUSED*/ 405 int 406 _dns_getnetbyname(rv, cb_data, ap) 407 void *rv; 408 void *cb_data; 409 va_list ap; 410 { 411 int anslen; 412 querybuf buf; 413 char qbuf[MAXDNAME]; 414 struct netent *np; 415 const char *net; 416 417 net = va_arg(ap, const char *); 418 strcpy(&qbuf[0], net); 419 anslen = res_search(qbuf, C_IN, T_PTR, (u_char *)(void *)&buf, 420 sizeof(buf)); 421 if (anslen < 0) { 422 #ifdef DEBUG 423 if (_res.options & RES_DEBUG) 424 printf("res_query failed\n"); 425 #endif 426 return NS_NOTFOUND; 427 } 428 np = getnetanswer(&buf, anslen, BYNAME); 429 430 *((struct netent **)rv) = np; 431 if (np == NULL) { 432 h_errno = HOST_NOT_FOUND; 433 return NS_NOTFOUND; 434 } 435 return NS_SUCCESS; 436 } 437 438 struct netent * 439 getnetbyname(net) 440 const char *net; 441 { 442 struct netent *np; 443 static const ns_dtab dtab[] = { 444 NS_FILES_CB(_getnetbyname, NULL) 445 { NSSRC_DNS, _dns_getnetbyname, NULL }, /* force -DHESIOD */ 446 NS_NIS_CB(_yp_getnetbyname, NULL) 447 { 0 } 448 }; 449 450 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 451 h_errno = NETDB_INTERNAL; 452 return (NULL); 453 } 454 455 np = NULL; 456 h_errno = NETDB_INTERNAL; 457 if (nsdispatch(&np, dtab, NSDB_NETWORKS, "getnetbyname", __nsdefaultsrc, 458 net) != NS_SUCCESS) 459 return (NULL); 460 h_errno = NETDB_SUCCESS; 461 return (np); 462 } 463 464 #ifdef YP 465 /*ARGSUSED*/ 466 int 467 _yp_getnetbyaddr(rv, cb_data, ap) 468 void *rv; 469 void *cb_data; 470 va_list ap; 471 { 472 struct netent *np; 473 char qbuf[MAXDNAME]; 474 unsigned int netbr[4]; 475 unsigned long net, net2; 476 int type, r; 477 478 net = va_arg(ap, unsigned long); 479 type = va_arg(ap, int); 480 481 if (type != AF_INET) 482 return NS_UNAVAIL; 483 484 if (!__ypdomain) { 485 if (_yp_check(&__ypdomain) == 0) 486 return NS_UNAVAIL; 487 } 488 np = NULL; 489 if (__ypcurrent) 490 free(__ypcurrent); 491 __ypcurrent = NULL; 492 for (r = 4, net2 = net; net2; net2 >>= 8) 493 netbr[--r] = (unsigned int)(net2 & 0xff); 494 switch (r) { 495 default: 496 return NS_UNAVAIL; 497 case 3: /* Class A */ 498 sprintf(qbuf, "%u", netbr[0]); 499 break; 500 case 2: /* Class B */ 501 sprintf(qbuf, "%u.%u", netbr[0], netbr[1]); 502 break; 503 case 1: /* Class C */ 504 sprintf(qbuf, "%u.%u.%u", netbr[0], netbr[1], netbr[2]); 505 break; 506 case 0: /* Class D - E */ 507 sprintf(qbuf, "%u.%u.%u.%u", netbr[0], netbr[1], netbr[2], 508 netbr[3]); 509 break; 510 } 511 r = yp_match(__ypdomain, "networks.byaddr", qbuf, (int)strlen(qbuf), 512 &__ypcurrent, &__ypcurrentlen); 513 if (r == 0) 514 np = _ypnetent(__ypcurrent); 515 516 *((struct netent **)rv) = np; 517 if (np == NULL) { 518 h_errno = HOST_NOT_FOUND; 519 return NS_NOTFOUND; 520 } 521 return NS_SUCCESS; 522 523 } 524 525 int 526 /*ARGSUSED*/ 527 _yp_getnetbyname(rv, cb_data, ap) 528 void *rv; 529 void *cb_data; 530 va_list ap; 531 { 532 struct netent *np; 533 const char *name; 534 int r; 535 536 name = va_arg(ap, const char *); 537 538 if (!__ypdomain) { 539 if (_yp_check(&__ypdomain) == 0) 540 return NS_UNAVAIL; 541 } 542 np = NULL; 543 if (__ypcurrent) 544 free(__ypcurrent); 545 __ypcurrent = NULL; 546 r = yp_match(__ypdomain, "networks.byname", name, (int)strlen(name), 547 &__ypcurrent, &__ypcurrentlen); 548 if (r == 0) 549 np = _ypnetent(__ypcurrent); 550 551 *((struct netent **)rv) = np; 552 if (np == NULL) { 553 h_errno = HOST_NOT_FOUND; 554 return NS_NOTFOUND; 555 } 556 return NS_SUCCESS; 557 } 558 559 struct netent * 560 _ypnetent(line) 561 char *line; 562 { 563 char *cp, *p, **q; 564 565 net_entry.n_name = line; 566 cp = strpbrk(line, " \t"); 567 if (cp == NULL) 568 return (NULL); 569 *cp++ = '\0'; 570 while (*cp == ' ' || *cp == '\t') 571 cp++; 572 p = strpbrk(cp, " \t"); 573 if (p != NULL) 574 *p++ = '\0'; 575 net_entry.n_net = inet_network(cp); 576 net_entry.n_addrtype = AF_INET; 577 q = net_entry.n_aliases = net_aliases; 578 if (p != NULL) { 579 cp = p; 580 while (cp && *cp) { 581 if (*cp == ' ' || *cp == '\t') { 582 cp++; 583 continue; 584 } 585 if (q < &net_aliases[MAXALIASES - 1]) 586 *q++ = cp; 587 cp = strpbrk(cp, " \t"); 588 if (cp != NULL) 589 *cp++ = '\0'; 590 } 591 } 592 *q = NULL; 593 594 return (&net_entry); 595 } 596 #endif 597
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