nis/nss_nis/nis-network.c

   1 /* Copyright (C) 1996-2019 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1996.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <nss.h>
  20 /* The following is an ugly trick to avoid a prototype declaration for
  21    _nss_nis_endgrent.  */
  22 #define _nss_nis_endnetent _nss_nis_endnetent_XXX
  23 #include <netdb.h>
  24 #undef _nss_nis_endnetent
  25 #include <ctype.h>
  26 #include <errno.h>
  27 #include <stdint.h>
  28 #include <string.h>
  29 #include <netinet/in.h>
  30 #include <arpa/inet.h>
  31 #include <libc-lock.h>
  32 #include <rpcsvc/yp.h>
  33 #include <rpcsvc/ypclnt.h>
  34
  35 #include "nss-nis.h"
  36
  37 /* Get the declaration of the parser function.  */
  38 #define ENTNAME netent
  39 #define EXTERN_PARSER
  40 #include <nss/nss_files/files-parse.c>
  41
  42 __libc_lock_define_initialized (static, lock)
  43
  44 static bool_t new_start = 1;
  45 static char *oldkey;
  46 static int oldkeylen;
  47
  48 enum nss_status
  49 _nss_nis_setnetent (int stayopen)
  50 {
  51   __libc_lock_lock (lock);
  52
  53   new_start = 1;
  54   if (oldkey != NULL)
  55     {
  56       free (oldkey);
  57       oldkey = NULL;
  58       oldkeylen = 0;
  59     }
  60
  61   __libc_lock_unlock (lock);
  62
  63   return NSS_STATUS_SUCCESS;
  64 }
  65 /* Make _nss_nis_endnetent an alias of _nss_nis_setnetent.  We do this
  66    even though the prototypes don't match.  The argument of setnetent
  67    is not used so this makes no difference.  */
  68 strong_alias (_nss_nis_setnetent, _nss_nis_endnetent)
  69
  70 static enum nss_status
  71 internal_nis_getnetent_r (struct netent *net, char *buffer, size_t buflen,
  72                           int *errnop, int *herrnop)
  73 {
  74   struct parser_data *data = (void *) buffer;
  75
  76   char *domain;
  77   if (__glibc_unlikely (yp_get_default_domain (&domain)))
  78     return NSS_STATUS_UNAVAIL;
  79
  80   /* Get the next entry until we found a correct one. */
  81   int parse_res;
  82   do
  83     {
  84       char *result;
  85       char *outkey;
  86       int len;
  87       int keylen;
  88       int yperr;
  89
  90       if (new_start)
  91         yperr = yp_first (domain, "networks.byname", &outkey, &keylen, &result,
  92                           &len);
  93       else
  94         yperr = yp_next (domain, "networks.byname", oldkey, oldkeylen, &outkey,
  95                          &keylen, &result, &len);
  96
  97       if (__glibc_unlikely (yperr != YPERR_SUCCESS))
  98         {
  99           enum nss_status retval = yperr2nss (yperr);
 100
 101           if (retval == NSS_STATUS_TRYAGAIN)
 102             {
 103               *herrnop = NETDB_INTERNAL;
 104               *errnop = errno;
 105             }
 106           return retval;
 107         }
 108
 109       if (__glibc_unlikely ((size_t) (len + 1) > buflen))
 110         {
 111           free (result);
 112           *errnop = ERANGE;
 113           *herrnop = NETDB_INTERNAL;
 114           return NSS_STATUS_TRYAGAIN;
 115         }
 116
 117       char *p = strncpy (buffer, result, len);
 118       buffer[len] = '\0';
 119       while (isspace (*p))
 120         ++p;
 121       free (result);
 122
 123       parse_res = _nss_files_parse_netent (p, net, data, buflen, errnop);
 124       if (__glibc_unlikely (parse_res == -1))
 125         {
 126           free (outkey);
 127           *herrnop = NETDB_INTERNAL;
 128           *errnop = ERANGE;
 129           return NSS_STATUS_TRYAGAIN;
 130         }
 131
 132       free (oldkey);
 133       oldkey = outkey;
 134       oldkeylen = keylen;
 135       new_start = 0;
 136     }
 137   while (!parse_res);
 138
 139   return NSS_STATUS_SUCCESS;
 140 }
 141
 142 enum nss_status
 143 _nss_nis_getnetent_r (struct netent *net, char *buffer, size_t buflen,
 144                       int *errnop, int *herrnop)
 145 {
 146   enum nss_status status;
 147
 148   __libc_lock_lock (lock);
 149
 150   status = internal_nis_getnetent_r (net, buffer, buflen, errnop, herrnop);
 151
 152   __libc_lock_unlock (lock);
 153
 154   return status;
 155 }
 156
 157 enum nss_status
 158 _nss_nis_getnetbyname_r (const char *name, struct netent *net, char *buffer,
 159                          size_t buflen, int *errnop, int *herrnop)
 160 {
 161   if (name == NULL)
 162     {
 163       *errnop = EINVAL;
 164       *herrnop = NETDB_INTERNAL;
 165       return NSS_STATUS_UNAVAIL;
 166     }
 167
 168   char *domain;
 169   if (__glibc_unlikely (yp_get_default_domain (&domain)))
 170     return NSS_STATUS_UNAVAIL;
 171
 172   struct parser_data *data = (void *) buffer;
 173   if (buflen < sizeof *data + 1)
 174     {
 175       *herrnop = NETDB_INTERNAL;
 176       *errnop = ERANGE;
 177       return NSS_STATUS_TRYAGAIN;
 178     }
 179
 180   /* Convert name to lowercase.  */
 181   size_t namlen = strlen (name);
 182   /* Limit name length to the maximum size of an RPC packet.  */
 183   if (namlen > UDPMSGSIZE)
 184     {
 185       *errnop = ERANGE;
 186       return NSS_STATUS_UNAVAIL;
 187     }
 188
 189   char name2[namlen + 1];
 190   size_t i;
 191
 192   for (i = 0; i < namlen; ++i)
 193     name2[i] = _tolower (name[i]);
 194   name2[i] = '\0';
 195
 196   char *result;
 197   int len;
 198   int yperr = yp_match (domain, "networks.byname", name2, namlen, &result,
 199                         &len);
 200
 201   if (__glibc_unlikely (yperr != YPERR_SUCCESS))
 202     {
 203       enum nss_status retval = yperr2nss (yperr);
 204
 205       if (retval == NSS_STATUS_TRYAGAIN)
 206         {
 207           *errnop = errno;
 208           *herrnop = NETDB_INTERNAL;
 209         }
 210       return retval;
 211     }
 212
 213   if (__glibc_unlikely ((size_t) (len + 1) > buflen))
 214     {
 215       free (result);
 216       *errnop = ERANGE;
 217       *herrnop = NETDB_INTERNAL;
 218       return NSS_STATUS_TRYAGAIN;
 219     }
 220
 221   char *p = strncpy (buffer, result, len);
 222   buffer[len] = '\0';
 223   while (isspace (*p))
 224     ++p;
 225   free (result);
 226
 227   int parse_res = _nss_files_parse_netent (p, net, data, buflen, errnop);
 228
 229   if (__glibc_unlikely (parse_res < 1))
 230     {
 231       *herrnop = NETDB_INTERNAL;
 232       if (parse_res == -1)
 233         return NSS_STATUS_TRYAGAIN;
 234       else
 235         return NSS_STATUS_NOTFOUND;
 236     }
 237   else
 238     return NSS_STATUS_SUCCESS;
 239 }
 240
 241 enum nss_status
 242 _nss_nis_getnetbyaddr_r (uint32_t addr, int type, struct netent *net,
 243                          char *buffer, size_t buflen, int *errnop,
 244                          int *herrnop)
 245 {
 246   char *domain;
 247   if (__glibc_unlikely (yp_get_default_domain (&domain)))
 248     return NSS_STATUS_UNAVAIL;
 249
 250   struct in_addr in = { .s_addr = htonl (addr) };
 251   char *buf = inet_ntoa (in);
 252   size_t blen = strlen (buf);
 253
 254   while (1)
 255     {
 256       char *result;
 257       int len;
 258
 259       int yperr = yp_match (domain, "networks.byaddr", buf, blen, &result,
 260                             &len);
 261
 262       if (__glibc_unlikely (yperr != YPERR_SUCCESS))
 263           {
 264             enum nss_status retval = yperr2nss (yperr);
 265
 266             if (retval == NSS_STATUS_NOTFOUND)
 267               {
 268                 if (buf[blen - 2] == '.' && buf[blen - 1] == '0')
 269                   {
 270                     /* Try again, but with trailing dot(s)
 271                        removed (one by one) */
 272                     buf[blen - 2] = '\0';
 273                     blen -= 2;
 274                     continue;
 275                   }
 276                 else
 277                   return NSS_STATUS_NOTFOUND;
 278               }
 279             else
 280               {
 281                 if (retval == NSS_STATUS_TRYAGAIN)
 282                   *errnop = errno;
 283                 return retval;
 284               }
 285           }
 286
 287       if (__glibc_unlikely ((size_t) (len + 1) > buflen))
 288         {
 289           free (result);
 290           *errnop = ERANGE;
 291           *herrnop = NETDB_INTERNAL;
 292           return NSS_STATUS_TRYAGAIN;
 293         }
 294
 295         char *p = strncpy (buffer, result, len);
 296         buffer[len] = '\0';
 297         while (isspace (*p))
 298           ++p;
 299         free (result);
 300
 301         int parse_res = _nss_files_parse_netent (p, net, (void *) buffer,
 302                                                  buflen, errnop);
 303
 304         if (__glibc_unlikely (parse_res < 1))
 305           {
 306             *herrnop = NETDB_INTERNAL;
 307             if (parse_res == -1)
 308               return NSS_STATUS_TRYAGAIN;
 309             else
 310               return NSS_STATUS_NOTFOUND;
 311           }
 312         else
 313           return NSS_STATUS_SUCCESS;
 314     }
 315 }