commands/password.c

   1 /*
   2  *  GRUB  --  GRand Unified Bootloader
   3  *  Copyright (C) 2009  Free Software Foundation, Inc.
   4  *
   5  *  GRUB is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  GRUB 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
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <grub/auth.h>
  20 #include <grub/list.h>
  21 #include <grub/mm.h>
  22 #include <grub/misc.h>
  23 #include <grub/env.h>
  24 #include <grub/normal.h>
  25 #include <grub/dl.h>
  26
  27 static grub_dl_t my_mod;
  28
  29 static grub_err_t
  30 check_password (const char *user,
  31                 void *password)
  32 {
  33   char entered[1024];
  34
  35   grub_memset (entered, 0, sizeof (entered));
  36
  37   if (!GRUB_GET_PASSWORD (entered, sizeof (entered) - 1))
  38     return GRUB_ACCESS_DENIED;
  39
  40   if (grub_auth_strcmp (entered, password) != 0)
  41     return GRUB_ACCESS_DENIED;
  42
  43   grub_auth_authenticate (user);
  44
  45   return GRUB_ERR_NONE;
  46 }
  47
  48 static grub_err_t
  49 grub_cmd_password (grub_command_t cmd __attribute__ ((unused)),
  50                    int argc, char **args)
  51 {
  52   grub_err_t err;
  53   char *pass;
  54
  55   if (argc != 2)
  56     return grub_error (GRUB_ERR_BAD_ARGUMENT, "Two arguments expected.");
  57
  58   pass = grub_strdup (args[1]);
  59   if (!pass)
  60     return grub_errno;
  61
  62   err = grub_auth_register_authentication (args[0], check_password, pass);
  63   if (err)
  64     {
  65       grub_free (pass);
  66       return err;
  67     }
  68   grub_dl_ref (my_mod);
  69   return GRUB_ERR_NONE;
  70 }
  71
  72 static grub_command_t cmd;
  73 \f
  74 GRUB_MOD_INIT(password)
  75 {
  76   my_mod = mod;
  77   cmd = grub_register_command ("password", grub_cmd_password,
  78                                "password USER PASSWORD",
  79                                "Set user password (plaintext). "
  80                                "Unrecommended and insecure.");
  81 }
  82
  83 GRUB_MOD_FINI(password)
  84 {
  85   grub_unregister_command (cmd);
  86 }