hesiod/nss_hesiod/hesiod-pwd.c

   1 /* Copyright (C) 1997-2024 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <hesiod.h>
  20 #include <pwd.h>
  21 #include <nss.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25
  26 NSS_DECLARE_MODULE_FUNCTIONS (hesiod)
  27
  28 /* Get the declaration of the parser function.  */
  29 #define ENTNAME pwent
  30 #define STRUCTURE passwd
  31 #define EXTERN_PARSER
  32 #include <nss/nss_files/files-parse.c>
  33
  34 enum nss_status
  35 _nss_hesiod_setpwent (int stayopen)
  36 {
  37   return NSS_STATUS_SUCCESS;
  38 }
  39
  40 enum nss_status
  41 _nss_hesiod_endpwent (void)
  42 {
  43   return NSS_STATUS_SUCCESS;
  44 }
  45
  46 static enum nss_status
  47 lookup (const char *name, const char *type, struct passwd *pwd,
  48         char *buffer, size_t buflen, int *errnop)
  49 {
  50   struct parser_data *data = (void *) buffer;
  51   size_t linebuflen;
  52   void *context;
  53   char **list;
  54   int parse_res;
  55   size_t len;
  56   int olderr = errno;
  57
  58   if (hesiod_init (&context) < 0)
  59     return NSS_STATUS_UNAVAIL;
  60
  61   list = hesiod_resolve (context, name, type);
  62   if (list == NULL)
  63     {
  64       int err = errno;
  65       hesiod_end (context);
  66       __set_errno (olderr);
  67       return err == ENOENT ? NSS_STATUS_NOTFOUND : NSS_STATUS_UNAVAIL;
  68     }
  69
  70   linebuflen = buffer + buflen - data->linebuffer;
  71   len = strlen (*list) + 1;
  72   if (linebuflen < len)
  73     {
  74       hesiod_free_list (context, list);
  75       hesiod_end (context);
  76       *errnop = ERANGE;
  77       return NSS_STATUS_TRYAGAIN;
  78     }
  79
  80   memcpy (data->linebuffer, *list, len);
  81   hesiod_free_list (context, list);
  82   hesiod_end (context);
  83
  84   parse_res = _nss_files_parse_pwent (buffer, pwd, data, buflen, errnop);
  85   if (parse_res < 1)
  86     {
  87       __set_errno (olderr);
  88       return parse_res == -1 ? NSS_STATUS_TRYAGAIN : NSS_STATUS_NOTFOUND;
  89     }
  90
  91   return NSS_STATUS_SUCCESS;
  92 }
  93
  94 enum nss_status
  95 _nss_hesiod_getpwnam_r (const char *name, struct passwd *pwd,
  96                         char *buffer, size_t buflen, int *errnop)
  97 {
  98   return lookup (name, "passwd", pwd, buffer, buflen, errnop);
  99 }
 100
 101 enum nss_status
 102 _nss_hesiod_getpwuid_r (uid_t uid, struct passwd *pwd,
 103                         char *buffer, size_t buflen, int *errnop)
 104 {
 105   char uidstr[21];      /* We will probably never have a gid_t with more
 106                            than 64 bits.  */
 107
 108   snprintf (uidstr, sizeof uidstr, "%d", uid);
 109
 110   return lookup (uidstr, "uid", pwd, buffer, buflen, errnop);
 111 }