nis/nss_nis/nis-alias.c

   1 /* Copyright (C) 1996 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 Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    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    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 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 = NULL;
  35 static int oldkeylen = 0;
  36
  37 static int
  38 _nss_nis_parse_aliasent (const char *key, char *alias, struct aliasent *result,
  39                          char *buffer, size_t buflen)
  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       __set_errno (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
 121 enum nss_status
 122 _nss_nis_endaliasent (void)
 123 {
 124   __libc_lock_lock (lock);
 125
 126   new_start = 1;
 127   if (oldkey != NULL)
 128     {
 129       free (oldkey);
 130       oldkey = NULL;
 131       oldkeylen = 0;
 132     }
 133
 134   __libc_lock_unlock (lock);
 135
 136   return NSS_STATUS_SUCCESS;
 137 }
 138
 139 static enum nss_status
 140 internal_nis_getaliasent_r (struct aliasent *alias, char *buffer,
 141                             size_t buflen)
 142 {
 143   char *domain;
 144   char *result;
 145   int len;
 146   char *outkey;
 147   int keylen;
 148   char *p;
 149   int parse_res;
 150
 151   if (yp_get_default_domain (&domain))
 152     return NSS_STATUS_UNAVAIL;
 153
 154   alias->alias_local = 0;
 155
 156   /* Get the next entry until we found a correct one. */
 157   do
 158     {
 159       enum nss_status retval;
 160
 161       if (new_start)
 162         retval = yperr2nss (yp_first (domain, "mail.aliases",
 163                                       &outkey, &keylen, &result, &len));
 164       else
 165         retval = yperr2nss ( yp_next (domain, "mail.aliases", oldkey,
 166                                       oldkeylen, &outkey, &keylen,
 167                                       &result, &len));
 168       if (retval != NSS_STATUS_SUCCESS)
 169         {
 170           if (retval == NSS_STATUS_TRYAGAIN)
 171             __set_errno (EAGAIN);
 172           return retval;
 173         }
 174
 175       if ((size_t) (len + 1) > buflen)
 176         {
 177           free (result);
 178           __set_errno (ERANGE);
 179           return NSS_STATUS_TRYAGAIN;
 180         }
 181       p = strncpy (buffer, result, len);
 182       buffer[len] = '\0';
 183       while (isspace (*p))
 184         ++p;
 185       free (result);
 186
 187       parse_res = _nss_nis_parse_aliasent (outkey, p, alias, buffer, buflen);
 188       if (parse_res == -1)
 189         {
 190           __set_errno (ERANGE);
 191           return NSS_STATUS_TRYAGAIN;
 192         }
 193
 194       free (oldkey);
 195       oldkey = outkey;
 196       oldkeylen = keylen;
 197       new_start = 0;
 198     }
 199   while (!parse_res);
 200
 201   return NSS_STATUS_SUCCESS;
 202 }
 203
 204 enum nss_status
 205 _nss_nis_getaliasent_r (struct aliasent *alias, char *buffer, size_t buflen)
 206 {
 207   enum nss_status status;
 208
 209   __libc_lock_lock (lock);
 210
 211   status = internal_nis_getaliasent_r (alias, buffer, buflen);
 212
 213   __libc_lock_unlock (lock);
 214
 215   return status;
 216 }
 217
 218 enum nss_status
 219 _nss_nis_getaliasbyname_r (const char *name, struct aliasent *alias,
 220                            char *buffer, size_t buflen)
 221 {
 222   enum nss_status retval;
 223   int parse_res;
 224   char *domain;
 225   char *result;
 226   int len;
 227   char *p;
 228
 229   if (name == NULL)
 230     {
 231       __set_errno (EINVAL);
 232       return NSS_STATUS_UNAVAIL;
 233     }
 234
 235   if (yp_get_default_domain (&domain))
 236     return NSS_STATUS_UNAVAIL;
 237
 238   retval = yperr2nss (yp_match (domain, "mail.aliases", name, strlen (name),
 239                                 &result, &len));
 240   if (retval != NSS_STATUS_SUCCESS)
 241     {
 242       if (retval == NSS_STATUS_TRYAGAIN)
 243         __set_errno (EAGAIN);
 244       return retval;
 245     }
 246
 247   if ((size_t) (len + 1) > buflen)
 248     {
 249       free (result);
 250       __set_errno (ERANGE);
 251       return NSS_STATUS_TRYAGAIN;
 252     }
 253
 254   p = strncpy (buffer, result, len);
 255   buffer[len] = '\0';
 256   while (isspace (*p))
 257     ++p;
 258   free (result);
 259
 260   alias->alias_local = 0;
 261   parse_res = _nss_nis_parse_aliasent (name, p, alias, buffer, buflen);
 262   if (parse_res == -1)
 263     return NSS_STATUS_TRYAGAIN;
 264   else
 265     if (parse_res == 0)
 266       return NSS_STATUS_NOTFOUND;
 267     else
 268       return NSS_STATUS_SUCCESS;
 269 }