nis/nss_nis/nis-alias.c

   1 /* Copyright (C) 1996-2002, 2003 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <nss.h>
  21 #include <ctype.h>
  22 #include <errno.h>
  23 #include <string.h>
  24 #include <aliases.h>
  25 #include <bits/libc-lock.h>
  26 #include <rpcsvc/yp.h>
  27 #include <rpcsvc/ypclnt.h>
  28
  29 #include "nss-nis.h"
  30
  31 __libc_lock_define_initialized (static, lock)
  32
  33 static bool_t new_start = 1;
  34 static char *oldkey;
  35 static int oldkeylen;
  36
  37 static int
  38 _nss_nis_parse_aliasent (const char *key, char *alias, struct aliasent *result,
  39                          char *buffer, size_t buflen, int *errnop)
  40 {
  41   char *first_unused = buffer + strlen (alias) + 1;
  42   size_t room_left =
  43     buflen - (buflen % __alignof__ (char *)) - strlen (alias) - 2;
  44   char *line;
  45   char *cp;
  46
  47   result->alias_members_len = 0;
  48   *first_unused = '\0';
  49   first_unused++;
  50   strcpy (first_unused, key);
  51
  52   if (first_unused[room_left - 1] != '\0')
  53     {
  54       /* The line is too long for our buffer.  */
  55     no_more_room:
  56       *errnop = ERANGE;
  57       return -1;
  58     }
  59
  60   result->alias_name = first_unused;
  61
  62   /* Terminate the line for any case.  */
  63   cp = strpbrk (alias, "#\n");
  64   if (cp != NULL)
  65     *cp = '\0';
  66
  67   first_unused += strlen (result->alias_name) + 1;
  68   /* Adjust the pointer so it is aligned for
  69      storing pointers.  */
  70   first_unused += __alignof__ (char *) - 1;
  71   first_unused -= ((first_unused - (char *) 0) % __alignof__ (char *));
  72   result->alias_members = (char **) first_unused;
  73
  74   line = alias;
  75
  76   while (*line != '\0')
  77     {
  78       /* Skip leading blanks.  */
  79       while (isspace (*line))
  80         line++;
  81
  82       if (*line == '\0')
  83         break;
  84
  85       if (room_left < sizeof (char *))
  86           goto no_more_room;
  87       room_left -= sizeof (char *);
  88       result->alias_members[result->alias_members_len] = line;
  89
  90       while (*line != '\0' && *line != ',')
  91         line++;
  92
  93       if (line != result->alias_members[result->alias_members_len])
  94         {
  95           *line = '\0';
  96           line++;
  97           result->alias_members_len++;
  98         }
  99     }
 100   return result->alias_members_len == 0 ? 0 : 1;
 101 }
 102
 103 enum nss_status
 104 _nss_nis_setaliasent (void)
 105 {
 106   __libc_lock_lock (lock);
 107
 108   new_start = 1;
 109   if (oldkey != NULL)
 110     {
 111       free (oldkey);
 112       oldkey = NULL;
 113       oldkeylen = 0;
 114     }
 115
 116   __libc_lock_unlock (lock);
 117
 118   return NSS_STATUS_SUCCESS;
 119 }
 120 /* The 'endaliasent' function is identical.  */
 121 strong_alias (_nss_nis_setaliasent, _nss_nis_endaliasent)
 122
 123 static enum nss_status
 124 internal_nis_getaliasent_r (struct aliasent *alias, char *buffer,
 125                             size_t buflen, int *errnop)
 126 {
 127   char *domain;
 128   char *result;
 129   int len;
 130   char *outkey;
 131   int keylen;
 132   char *p;
 133   int parse_res;
 134
 135   if (yp_get_default_domain (&domain))
 136     return NSS_STATUS_UNAVAIL;
 137
 138   alias->alias_local = 0;
 139
 140   /* Get the next entry until we found a correct one. */
 141   do
 142     {
 143       enum nss_status retval;
 144
 145       if (new_start)
 146         retval = yperr2nss (yp_first (domain, "mail.aliases",
 147                                       &outkey, &keylen, &result, &len));
 148       else
 149         retval = yperr2nss ( yp_next (domain, "mail.aliases", oldkey,
 150                                       oldkeylen, &outkey, &keylen,
 151                                       &result, &len));
 152       if (retval != NSS_STATUS_SUCCESS)
 153         {
 154           if (retval == NSS_STATUS_TRYAGAIN)
 155             *errnop = errno;
 156           return retval;
 157         }
 158
 159       if ((size_t) (len + 1) > buflen)
 160         {
 161           free (result);
 162           *errnop = ERANGE;
 163           return NSS_STATUS_TRYAGAIN;
 164         }
 165       p = strncpy (buffer, result, len);
 166       buffer[len] = '\0';
 167       while (isspace (*p))
 168         ++p;
 169       free (result);
 170
 171       parse_res = _nss_nis_parse_aliasent (outkey, p, alias, buffer, buflen,
 172                                            errnop);
 173       if (parse_res == -1)
 174         {
 175           free (outkey);
 176           *errnop = ERANGE;
 177           return NSS_STATUS_TRYAGAIN;
 178         }
 179
 180       free (oldkey);
 181       oldkey = outkey;
 182       oldkeylen = keylen;
 183       new_start = 0;
 184     }
 185   while (!parse_res);
 186
 187   return NSS_STATUS_SUCCESS;
 188 }
 189
 190 enum nss_status
 191 _nss_nis_getaliasent_r (struct aliasent *alias, char *buffer, size_t buflen,
 192                         int *errnop)
 193 {
 194   enum nss_status status;
 195
 196   __libc_lock_lock (lock);
 197
 198   status = internal_nis_getaliasent_r (alias, buffer, buflen, errnop);
 199
 200   __libc_lock_unlock (lock);
 201
 202   return status;
 203 }
 204
 205 enum nss_status
 206 _nss_nis_getaliasbyname_r (const char *name, struct aliasent *alias,
 207                            char *buffer, size_t buflen, int *errnop)
 208 {
 209   enum nss_status retval;
 210   int parse_res;
 211   char *domain;
 212   char *result;
 213   int len;
 214   char *p;
 215   size_t namlen = strlen (name);
 216   char name2[namlen + 1];
 217   size_t i;
 218
 219   if (name == NULL)
 220     {
 221       *errnop = EINVAL;
 222       return NSS_STATUS_UNAVAIL;
 223     }
 224
 225   if (yp_get_default_domain (&domain))
 226     return NSS_STATUS_UNAVAIL;
 227
 228   /* Convert name to lowercase.  */
 229   for (i = 0; i < namlen; ++i)
 230     name2[i] = _tolower (name[i]);
 231   name2[i] = '\0';
 232
 233   retval = yperr2nss (yp_match (domain, "mail.aliases", name2, namlen,
 234                                 &result, &len));
 235
 236   if (retval != NSS_STATUS_SUCCESS)
 237     {
 238       if (retval == NSS_STATUS_TRYAGAIN)
 239         *errnop = errno;
 240       return retval;
 241     }
 242
 243   if ((size_t) (len + 1) > buflen)
 244     {
 245       free (result);
 246       *errnop = ERANGE;
 247       return NSS_STATUS_TRYAGAIN;
 248     }
 249
 250   p = strncpy (buffer, result, len);
 251   buffer[len] = '\0';
 252   while (isspace (*p))
 253     ++p;
 254   free (result);
 255
 256   alias->alias_local = 0;
 257   parse_res = _nss_nis_parse_aliasent (name, p, alias, buffer, buflen, errnop);
 258   if (parse_res < 1)
 259     {
 260       if (parse_res == -1)
 261         return NSS_STATUS_TRYAGAIN;
 262       else
 263         return NSS_STATUS_NOTFOUND;
 264     }
 265
 266   return NSS_STATUS_SUCCESS;
 267 }