lib/libc/net/getnetnamadr.c

   1 /*-
   2  * Copyright (c) 1994, Garrett Wollman
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND
  14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  23  * SUCH DAMAGE.
  24  *
  25  * $FreeBSD: src/lib/libc/net/getnetnamadr.c,v 1.23 2006/04/28 12:03:35 ume Exp $
  26  * $DragonFly: src/lib/libc/net/getnetnamadr.c,v 1.4 2005/11/13 02:04:47 swildner Exp $
  27  */
  28
  29 #include "namespace.h"
  30 #include "reentrant.h"
  31 #include <sys/param.h>
  32 #include <sys/socket.h>
  33 #include <netinet/in.h>
  34 #include <arpa/inet.h>
  35 #include <netdb.h>
  36 #include <stdio.h>
  37 #include <ctype.h>
  38 #include <errno.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41 #include <stdarg.h>
  42 #include <nsswitch.h>
  43 #include "un-namespace.h"
  44 #include "netdb_private.h"
  45 #ifdef NS_CACHING
  46 #include "nscache.h"
  47 #endif
  48
  49 extern int _ht_getnetbyname(void *, void *, va_list);
  50 extern int _dns_getnetbyname(void *, void *, va_list);
  51 extern int _nis_getnetbyname(void *, void *, va_list);
  52 extern int _ht_getnetbyaddr(void *, void *, va_list);
  53 extern int _dns_getnetbyaddr(void *, void *, va_list);
  54 extern int _nis_getnetbyaddr(void *, void *, va_list);
  55
  56 /* Network lookup order if nsswitch.conf is broken or nonexistant */
  57 static const ns_src default_src[] = {
  58         { NSSRC_FILES, NS_SUCCESS },
  59         { NSSRC_DNS, NS_SUCCESS },
  60         { 0 }
  61 };
  62
  63 NETDB_THREAD_ALLOC(netent_data)
  64 NETDB_THREAD_ALLOC(netdata)
  65
  66 #ifdef NS_CACHING
  67 static int
  68 net_id_func(char *buffer, size_t *buffer_size, va_list ap, void *cache_mdata)
  69 {
  70         char *name;
  71         uint32_t net;
  72         int type;
  73
  74         size_t desired_size, size;
  75         enum nss_lookup_type lookup_type;
  76         int res = NS_UNAVAIL;
  77
  78         lookup_type = (enum nss_lookup_type)cache_mdata;
  79         switch (lookup_type) {
  80         case nss_lt_name:
  81                 name = va_arg(ap, char *);
  82
  83                 size = strlen(name);
  84                 desired_size = sizeof(enum nss_lookup_type) + size + 1;
  85                 if (desired_size > *buffer_size) {
  86                         res = NS_RETURN;
  87                         goto fin;
  88                 }
  89
  90                 memcpy(buffer, &lookup_type, sizeof(enum nss_lookup_type));
  91                 memcpy(buffer + sizeof(enum nss_lookup_type), name, size + 1);
  92
  93                 res = NS_SUCCESS;
  94                 break;
  95         case nss_lt_id:
  96                 net = va_arg(ap, uint32_t);
  97                 type = va_arg(ap, int);
  98
  99                 desired_size = sizeof(enum nss_lookup_type) +
 100                     sizeof(uint32_t) + sizeof(int);
 101                 if (desired_size > *buffer_size) {
 102                         res = NS_RETURN;
 103                         goto fin;
 104                 }
 105
 106                 memcpy(buffer, &lookup_type, sizeof(enum nss_lookup_type));
 107                 memcpy(buffer + sizeof(enum nss_lookup_type), &net,
 108                     sizeof(uint32_t));
 109                 memcpy(buffer + sizeof(enum nss_lookup_type) + sizeof(uint32_t),
 110                     &type, sizeof(int));
 111
 112                 res = NS_SUCCESS;
 113                 break;
 114         default:
 115                 /* should be unreachable */
 116                 return (NS_UNAVAIL);
 117         }
 118
 119 fin:
 120         *buffer_size = desired_size;
 121         return (res);
 122 }
 123
 124
 125 static int
 126 net_marshal_func(char *buffer, size_t *buffer_size, void *retval, va_list ap,
 127                  void *cache_mdata)
 128 {
 129         char *name;
 130         uint32_t net;
 131         int type;
 132         struct netent *ne;
 133         char *orig_buf;
 134         size_t orig_buf_size;
 135
 136         struct netent new_ne;
 137         size_t desired_size, size, aliases_size;
 138         char *p;
 139         char **alias;
 140
 141         switch ((enum nss_lookup_type)cache_mdata) {
 142         case nss_lt_name:
 143                 name = va_arg(ap, char *);
 144                 break;
 145         case nss_lt_id:
 146                 net = va_arg(ap, uint32_t);
 147                 type = va_arg(ap, int);
 148         break;
 149         case nss_lt_all:
 150                 break;
 151         default:
 152                 /* should be unreachable */
 153                 return (NS_UNAVAIL);
 154         }
 155
 156         ne = va_arg(ap, struct netent *);
 157         orig_buf = va_arg(ap, char *);
 158         orig_buf_size = va_arg(ap, size_t);
 159
 160         desired_size = _ALIGNBYTES + sizeof(struct netent) + sizeof(char *);
 161         if (ne->n_name != NULL)
 162                 desired_size += strlen(ne->n_name) + 1;
 163
 164         if (ne->n_aliases != NULL) {
 165                 aliases_size = 0;
 166                 for (alias = ne->n_aliases; *alias; ++alias) {
 167                         desired_size += strlen(*alias) + 1;
 168                         ++aliases_size;
 169                 }
 170
 171                 desired_size += _ALIGNBYTES +
 172                     (aliases_size + 1) * sizeof(char *);
 173         }
 174
 175         if (*buffer_size < desired_size) {
 176                 /* this assignment is here for future use */
 177                 *buffer_size = desired_size;
 178                 return (NS_RETURN);
 179         }
 180
 181         memcpy(&new_ne, ne, sizeof(struct netent));
 182
 183         *buffer_size = desired_size;
 184         memset(buffer, 0, desired_size);
 185         p = buffer + sizeof(struct netent) + sizeof(char *);
 186         memcpy(buffer + sizeof(struct netent), &p, sizeof(char *));
 187         p = (char *)_ALIGN(p);
 188
 189         if (new_ne.n_name != NULL) {
 190                 size = strlen(new_ne.n_name);
 191                 memcpy(p, new_ne.n_name, size);
 192                 new_ne.n_name = p;
 193                 p += size + 1;
 194         }
 195
 196         if (new_ne.n_aliases != NULL) {
 197                 p = (char *)_ALIGN(p);
 198                 memcpy(p, new_ne.n_aliases, sizeof(char *) * aliases_size);
 199                 new_ne.n_aliases = (char **)p;
 200                 p += sizeof(char *) * (aliases_size + 1);
 201
 202                 for (alias = new_ne.n_aliases; *alias; ++alias) {
 203                         size = strlen(*alias);
 204                         memcpy(p, *alias, size);
 205                         *alias = p;
 206                         p += size + 1;
 207                 }
 208         }
 209
 210         memcpy(buffer, &new_ne, sizeof(struct netent));
 211         return (NS_SUCCESS);
 212 }
 213
 214 static int
 215 net_unmarshal_func(char *buffer, size_t buffer_size, void *retval, va_list ap,
 216                    void *cache_mdata)
 217 {
 218         char *name;
 219         uint32_t net;
 220         int type;
 221         struct netent *ne;
 222         char *orig_buf;
 223         size_t orig_buf_size;
 224         int *ret_errno;
 225
 226         char *p;
 227         char **alias;
 228
 229         switch ((enum nss_lookup_type)cache_mdata) {
 230         case nss_lt_name:
 231                 name = va_arg(ap, char *);
 232                 break;
 233         case nss_lt_id:
 234                 net = va_arg(ap, uint32_t);
 235                 type = va_arg(ap, int);
 236                 break;
 237         case nss_lt_all:
 238                 break;
 239         default:
 240                 /* should be unreachable */
 241                 return (NS_UNAVAIL);
 242         }
 243
 244         ne = va_arg(ap, struct netent *);
 245         orig_buf = va_arg(ap, char *);
 246         orig_buf_size = va_arg(ap, size_t);
 247         ret_errno = va_arg(ap, int *);
 248
 249         if (orig_buf_size <
 250             buffer_size - sizeof(struct netent) - sizeof(char *)) {
 251                 *ret_errno = ERANGE;
 252                 return (NS_RETURN);
 253         }
 254
 255         memcpy(ne, buffer, sizeof(struct netent));
 256         memcpy(&p, buffer + sizeof(struct netent), sizeof(char *));
 257
 258         orig_buf = (char *)_ALIGN(orig_buf);
 259         memcpy(orig_buf, buffer + sizeof(struct netent) + sizeof(char *) +
 260             _ALIGN(p) - (size_t)p,
 261             buffer_size - sizeof(struct netent) - sizeof(char *) -
 262             _ALIGN(p) + (size_t)p);
 263         p = (char *)_ALIGN(p);
 264
 265         NS_APPLY_OFFSET(ne->n_name, orig_buf, p, char *);
 266         if (ne->n_aliases != NULL) {
 267                 NS_APPLY_OFFSET(ne->n_aliases, orig_buf, p, char **);
 268
 269                 for (alias = ne->n_aliases; *alias; ++alias)
 270                         NS_APPLY_OFFSET(*alias, orig_buf, p, char *);
 271         }
 272
 273         if (retval != NULL)
 274                 *((struct netent **)retval) = ne;
 275
 276         return (NS_SUCCESS);
 277 }
 278 #endif /* NS_CACHING */
 279
 280 static void
 281 netent_data_free(void *ptr)
 282 {
 283         struct netent_data *ned = ptr;
 284
 285         if (ned == NULL)
 286                 return;
 287         ned->stayopen = 0;
 288         _endnethtent(ned);
 289         free(ned);
 290 }
 291
 292 static void
 293 netdata_free(void *ptr)
 294 {
 295         free(ptr);
 296 }
 297
 298 int
 299 __copy_netent(struct netent *ne, struct netent *nptr, char *buf, size_t buflen)
 300 {
 301         char *cp;
 302         int i, n;
 303         int numptr, len;
 304
 305         /* Find out the amount of space required to store the answer. */
 306         numptr = 1; /* NULL ptr */
 307         len = (char *)ALIGN(buf) - buf;
 308         for (i = 0; ne->n_aliases[i]; i++, numptr++) {
 309                 len += strlen(ne->n_aliases[i]) + 1;
 310         }
 311         len += strlen(ne->n_name) + 1;
 312         len += numptr * sizeof(char*);
 313
 314         if (len > (int)buflen) {
 315                 errno = ERANGE;
 316                 return (-1);
 317         }
 318
 319         /* copy net value and type */
 320         nptr->n_addrtype = ne->n_addrtype;
 321         nptr->n_net = ne->n_net;
 322
 323         cp = (char *)ALIGN(buf) + numptr * sizeof(char *);
 324
 325         /* copy official name */
 326         n = strlen(ne->n_name) + 1;
 327         strcpy(cp, ne->n_name);
 328         nptr->n_name = cp;
 329         cp += n;
 330
 331         /* copy aliases */
 332         nptr->n_aliases = (char **)ALIGN(buf);
 333         for (i = 0 ; ne->n_aliases[i]; i++) {
 334                 n = strlen(ne->n_aliases[i]) + 1;
 335                 strcpy(cp, ne->n_aliases[i]);
 336                 nptr->n_aliases[i] = cp;
 337                 cp += n;
 338         }
 339         nptr->n_aliases[i] = NULL;
 340
 341         return (0);
 342 }
 343
 344 int
 345 getnetbyname_r(const char *name, struct netent *ne, char *buffer,
 346                size_t buflen, struct netent **result, int *h_errorp)
 347 {
 348 #ifdef NS_CACHING
 349         static const nss_cache_info cache_info =
 350                 NS_COMMON_CACHE_INFO_INITIALIZER(
 351                 networks, (void *)nss_lt_name,
 352                 net_id_func, net_marshal_func, net_unmarshal_func);
 353 #endif
 354         static const ns_dtab dtab[] = {
 355                 NS_FILES_CB(_ht_getnetbyname, NULL)
 356                 { NSSRC_DNS, _dns_getnetbyname, NULL },
 357                 NS_NIS_CB(_nis_getnetbyname, NULL) /* force -DHESIOD */
 358 #ifdef NS_CACHING
 359                 NS_CACHE_CB(&cache_info)
 360 #endif
 361                 { 0 }
 362         };
 363         int rval, ret_errno;
 364
 365         rval = _nsdispatch((void *)result, dtab, NSDB_NETWORKS,
 366             "getnetbyname_r", default_src, name, ne, buffer, buflen,
 367             &ret_errno, h_errorp);
 368
 369         return ((rval == NS_SUCCESS) ? 0 : -1);
 370 }
 371
 372 int
 373 getnetbyaddr_r(uint32_t addr, int af, struct netent *ne, char *buffer,
 374                size_t buflen, struct netent **result, int *h_errorp)
 375 {
 376 #ifdef NS_CACHING
 377         static const nss_cache_info cache_info =
 378                 NS_COMMON_CACHE_INFO_INITIALIZER(
 379                 networks, (void *)nss_lt_id,
 380                 net_id_func, net_marshal_func, net_unmarshal_func);
 381 #endif
 382         static const ns_dtab dtab[] = {
 383                 NS_FILES_CB(_ht_getnetbyaddr, NULL)
 384                 { NSSRC_DNS, _dns_getnetbyaddr, NULL },
 385                 NS_NIS_CB(_nis_getnetbyaddr, NULL) /* force -DHESIOD */
 386 #ifdef NS_CACHING
 387                 NS_CACHE_CB(&cache_info)
 388 #endif
 389                 { 0 }
 390         };
 391         int rval, ret_errno;
 392
 393         rval = _nsdispatch((void *)result, dtab, NSDB_NETWORKS,
 394             "getnetbyaddr_r", default_src, addr, af, ne, buffer, buflen,
 395             &ret_errno, h_errorp);
 396
 397         return ((rval == NS_SUCCESS) ? 0 : -1);
 398 }
 399
 400 struct netent *
 401 getnetbyname(const char *name)
 402 {
 403         struct netdata *nd;
 404         struct netent *rval;
 405         int ret_h_errno;
 406
 407         if ((nd = __netdata_init()) == NULL)
 408                 return (NULL);
 409         if (getnetbyname_r(name, &nd->net, nd->data, sizeof(nd->data), &rval,
 410             &ret_h_errno) != 0)
 411                 return (NULL);
 412         return (rval);
 413 }
 414
 415 struct netent *
 416 getnetbyaddr(uint32_t addr, int af)
 417 {
 418         struct netdata *nd;
 419         struct netent *rval;
 420         int ret_h_errno;
 421
 422         if ((nd = __netdata_init()) == NULL)
 423                 return (NULL);
 424         if (getnetbyaddr_r(addr, af, &nd->net, nd->data, sizeof(nd->data),
 425             &rval, &ret_h_errno) != 0)
 426                 return (NULL);
 427         return (rval);
 428 }
 429
 430 void
 431 setnetent(int stayopen)
 432 {
 433         struct netent_data *ned;
 434
 435         if ((ned = __netent_data_init()) == NULL)
 436                 return;
 437         _setnethtent(stayopen, ned);
 438         _setnetdnsent(stayopen);
 439 }
 440
 441 void
 442 endnetent(void)
 443 {
 444         struct netent_data *ned;
 445
 446         if ((ned = __netent_data_init()) == NULL)
 447                 return;
 448         _endnethtent(ned);
 449         _endnetdnsent();
 450 }