hesiod/nss_hesiod/hesiod-grp.c

   1 /* Copyright (C) 1997, 1999, 2000 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Mark Kettenis <kettenis@phys.uva.nl>, 1997.
   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 <ctype.h>
  21 #include <errno.h>
  22 #include <grp.h>
  23 #include <hesiod.h>
  24 #include <nss.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <sys/param.h>
  29
  30 #include "nss_hesiod.h"
  31
  32 /* Get the declaration of the parser function.  */
  33 #define ENTNAME grent
  34 #define STRUCTURE group
  35 #define EXTERN_PARSER
  36 #include <nss/nss_files/files-parse.c>
  37
  38 enum nss_status
  39 _nss_hesiod_setgrent (int stayopen)
  40 {
  41   return NSS_STATUS_SUCCESS;
  42 }
  43
  44 enum nss_status
  45 _nss_hesiod_endgrent (void)
  46 {
  47   return NSS_STATUS_SUCCESS;
  48 }
  49
  50 static enum nss_status
  51 lookup (const char *name, const char *type, struct group *grp,
  52         char *buffer, size_t buflen, int *errnop)
  53 {
  54   struct parser_data *data = (void *) buffer;
  55   size_t linebuflen;
  56   void *context;
  57   char **list;
  58   int parse_res;
  59   size_t len;
  60
  61   context = _nss_hesiod_init ();
  62   if (context == NULL)
  63     return NSS_STATUS_UNAVAIL;
  64
  65   list = hesiod_resolve (context, name, type);
  66   if (list == NULL)
  67     {
  68       hesiod_end (context);
  69       return errno == ENOENT ? NSS_STATUS_NOTFOUND : NSS_STATUS_UNAVAIL;
  70     }
  71
  72   linebuflen = buffer + buflen - data->linebuffer;
  73   len = strlen (*list) + 1;
  74   if (linebuflen < len)
  75     {
  76       hesiod_free_list (context, list);
  77       hesiod_end (context);
  78       *errnop = ERANGE;
  79       return NSS_STATUS_TRYAGAIN;
  80     }
  81
  82   memcpy (data->linebuffer, *list, len);
  83   hesiod_free_list (context, list);
  84   hesiod_end (context);
  85
  86   parse_res = _nss_files_parse_grent (buffer, grp, data, buflen, errnop);
  87   if (parse_res < 1)
  88     return parse_res == -1 ? NSS_STATUS_TRYAGAIN : NSS_STATUS_NOTFOUND;
  89
  90   return NSS_STATUS_SUCCESS;
  91 }
  92
  93 enum nss_status
  94 _nss_hesiod_getgrnam_r (const char *name, struct group *grp,
  95                         char *buffer, size_t buflen, int *errnop)
  96 {
  97   return lookup (name, "group", grp, buffer, buflen, errnop);
  98 }
  99
 100 enum nss_status
 101 _nss_hesiod_getgrgid_r (gid_t gid, struct group *grp,
 102                         char *buffer, size_t buflen, int *errnop)
 103 {
 104   char gidstr[21];      /* We will probably never have a gid_t with more
 105                            than 64 bits.  */
 106
 107   snprintf (gidstr, sizeof gidstr, "%d", gid);
 108
 109   return lookup (gidstr, "gid", grp, buffer, buflen, errnop);
 110 }
 111
 112 static int
 113 internal_gid_in_list (const gid_t *list, const gid_t g, long int len)
 114 {
 115   while (len > 0)
 116     {
 117       if (*list == g)
 118         return 1;
 119       --len;
 120       ++list;
 121     }
 122   return 0;
 123 }
 124
 125 static enum nss_status
 126 internal_gid_from_group (void *context, const char *groupname, gid_t *group)
 127 {
 128   char **grp_res;
 129   enum nss_status status = NSS_STATUS_NOTFOUND;
 130
 131   grp_res = hesiod_resolve (context, groupname, "group");
 132   if (grp_res != NULL && *grp_res != NULL)
 133     {
 134       char *p = *grp_res;
 135
 136       while (*p != '\0' && *p != ':')
 137         ++p;
 138       while (*p != '\0' && *p == ':')
 139         ++p;
 140       while (*p != '\0' && *p != ':')
 141         ++p;
 142       while (*p != '\0' && *p == ':')
 143         ++p;
 144       if (*p == ':')
 145         {
 146           char *endp;
 147           char *q = ++p;
 148           long int val;
 149
 150           q = p;
 151           while (*q != '\0' && *q != ':')
 152             ++q;
 153
 154           val = strtol (p, &endp, 10);
 155           if (sizeof (gid_t) == sizeof (long int) || (gid_t) val == val)
 156             {
 157               *group = val;
 158               if (endp == q && endp != p)
 159                 status = NSS_STATUS_SUCCESS;
 160             }
 161         }
 162       hesiod_free_list (context, grp_res);
 163     }
 164   return status;
 165 }
 166
 167 enum nss_status
 168 _nss_hesiod_initgroups_dyn (const char *user, gid_t group, long int *start,
 169                             long int *size, gid_t **groupsp, long int limit,
 170                             int *errnop)
 171 {
 172   enum nss_status status = NSS_STATUS_SUCCESS;
 173   char **list = NULL;
 174   char *p;
 175   void *context;
 176   gid_t *groups = *groupsp;
 177   int save_errno;
 178
 179   context = _nss_hesiod_init ();
 180   if (context == NULL)
 181     return NSS_STATUS_UNAVAIL;
 182
 183   list = hesiod_resolve (context, user, "grplist");
 184
 185   if (list == NULL)
 186     {
 187       hesiod_end (context);
 188       return errno == ENOENT ? NSS_STATUS_NOTFOUND : NSS_STATUS_UNAVAIL;
 189     }
 190
 191   if (!internal_gid_in_list (groups, group, *start))
 192     {
 193       if (__builtin_expect (*start == *size, 0))
 194         {
 195           /* Need a bigger buffer.  */
 196           gid_t *newgroups;
 197           long int newsize;
 198
 199           if (limit > 0 && *size == limit)
 200             /* We reached the maximum.  */
 201             goto done;
 202
 203           if (limit <= 0)
 204             newsize = 2 * *size;
 205           else
 206             newsize = MIN (limit, 2 * *size);
 207
 208           newgroups = realloc (groups, newsize * sizeof (*groups));
 209           if (newgroups == NULL)
 210             goto done;
 211           *groupsp = groups = newgroups;
 212           *size = newsize;
 213         }
 214
 215       groups[(*start)++] = group;
 216     }
 217
 218   save_errno = errno;
 219
 220   p = *list;
 221   while (*p != '\0')
 222     {
 223       char *endp;
 224       char *q;
 225       long int val;
 226
 227       status = NSS_STATUS_NOTFOUND;
 228
 229       q = p;
 230       while (*q != '\0' && *q != ':' && *q != ',')
 231         ++q;
 232
 233       if (*q != '\0')
 234         *q++ = '\0';
 235
 236       __set_errno (0);
 237       val = strtol (p, &endp, 10);
 238       /* Test whether the number is representable in a variable of
 239          type `gid_t'.  If not ignore the number.  */
 240       if ((sizeof (gid_t) == sizeof (long int) || (gid_t) val == val)
 241           && errno == 0)
 242         {
 243           if (*endp == '\0' && endp != p)
 244             {
 245               group = val;
 246               status = NSS_STATUS_SUCCESS;
 247             }
 248           else
 249             status = internal_gid_from_group (context, p, &group);
 250
 251           if (status == NSS_STATUS_SUCCESS
 252               && !internal_gid_in_list (groups, group, *start))
 253             {
 254               if (__builtin_expect (*start == *size, 0))
 255                 {
 256                   /* Need a bigger buffer.  */
 257                   gid_t *newgroups;
 258                   long int newsize;
 259
 260                   if (limit > 0 && *size == limit)
 261                     /* We reached the maximum.  */
 262                     goto done;
 263
 264                   if (limit <= 0)
 265                     newsize = 2 * *size;
 266                   else
 267                     newsize = MIN (limit, 2 * *size);
 268
 269                   newgroups = realloc (groups, newsize * sizeof (*groups));
 270                   if (newgroups == NULL)
 271                     goto done;
 272                   *groupsp = groups = newgroups;
 273                   *size = newsize;
 274                 }
 275
 276               groups[(*start)++] = group;
 277             }
 278         }
 279
 280       p = q;
 281     }
 282
 283   __set_errno (save_errno);
 284
 285  done:
 286   hesiod_free_list (context, list);
 287   hesiod_end (context);
 288
 289   return NSS_STATUS_SUCCESS;
 290 }